Note: Images of the original pages are available through Digital Case, the Kelvin Smith Library, Case Western Reserve University. See http://digitalcase. Case. Edu:9000/fedora/get/ksl:binmin00/binmin00. Pdf Transcriber's Note: References are made to footnotes in other footnotes and index. The footnotes are serially numbered and placed at the end of each chapter. Consequently the references in the footnotes and index have been corrected to indicate the footnote number. International Scientific Series. Volume LXXXIX. (The International Scientific Series) Edited by F. Legge THE MIND AND THE BRAIN by ALFRED BINET Directeur du Laboratoire de Psychologieà la Sorbonne Being the Authorised Translation of _L'Âme et le Corps_ LondonKegan Paul, Trench, Trübner & Co. LtdDryden House, Gerrard Street, W. 1907 CONTENTS BOOK I THE DEFINITION OF MATTER CHAPTER I INTRODUCTION The distinction between mind and matter--Knowable nothomogeneous--Criterion employed, enumeration not concepts CHAPTER II OUR KNOWLEDGE OF EXTERNAL OBJECTS ONLY SENSATION Modern theories of matter--Outer world only known to us by oursensations--Instances--Mill's approval of proposition, and itsdefects--Nervous system only intermediary between self and outerworld--The great X of Matter--Nervous system does not give us trueimage--Müller's law of specificity of the nerves--The nervous systemitself a sensation--Relations of sensation with the unknowable theaffair of metaphysics CHAPTER III THE MECHANICAL THEORIES OF MATTER ARE ONLY SYMBOLS Physicists vainly endeavour to reduce the rôle ofsensation--Mathematical, energetical, and mechanical theories ofuniverse--Mechanical model formed from sensation--Instance oftuning-fork--No one sensation any right to hegemony over others CHAPTER IV ANSWERS TO SOME OBJECTIONS, AND SUMMARY Objections of spiritualists--Of German authors who contend thatnervous system does give true image--Of metaphysicians--Common groundof objection that nervous system not intermediary--Answer tothis--Summary of preceding chapters BOOK II THE DEFINITION OF MIND CHAPTER I THE DISTINCTION BETWEEN COGNITION AND ITS OBJECT Necessity for inventory of mental phenomena--Objects of cognition andacts of cognition--Definition of consciousness CHAPTER II DEFINITION OF SENSATION Sensation defined by experimental psychology--A state ofconsciousness--Considered self-evident by Mill, Renouvier, andHume--Psycho-physical according to Reid and Hamilton--Reasons infavour of last definition--Other opinions examined and refuted CHAPTER III DEFINITION OF THE IMAGE Perception and ideation cannot be separated--Perception constituted byaddition of image to sensation--Hallucinations--Objections anticipatedand answered CHAPTER IV DEFINITION OF THE EMOTIONS Contrary opinions as to nature of emotions--Emotion a phenomenon _suigeneris_--Intellectualist theory of emotion supported by Lange andJames--Is emotion only a perception? Is effort?--Question leftunanswered CHAPTER V DEFINITION OF THE CONSCIOUSNESS--THE RELATION SUBJECT-OBJECT Can thoughts be divided into subject and object?--This division cannotapply to the consciousness--Subject of cognition itself anobject--James' opinion examined--Opinion that subject is spiritualsubstance and consciousness its faculty refuted CHAPTER VI DEFINITION OF THE CONSCIOUSNESS--CATEGORIES OF THE UNDERSTANDING Principle of relativity doubted--Tables of categories: Aristotle, Kant, and Renouvier--Kantian idealism--Phenomenism of Berkeley examined andrejected--Argument of _a priorists_--The intelligence only an inactiveconsciousness--Huxley's epiphenomenal consciousness--Is theconsciousness necessary?--Impossibility of answering this question CHAPTER VII DEFINITION OF THE CONSCIOUSNESS--THE SEPARABILITY OF THE CONSCIOUSNESSFROM ITS OBJECT--DISCUSSION OF IDEALISM Can the consciousness be separated from its object?--Idealistsconsider the object a modality of the consciousness and thusinseparable, from it--Futility of this doctrine--Object can existwithout consciousness CHAPTER VIII DEFINITION OF THE CONSCIOUSNESS--THE SEPARATION OF THE CONSCIOUSNESSFROM ITS OBJECT--THE UNCONSCIOUS Can ideas exist without consciousness?--No consciousness without anobject--Can the consciousness die?--Enfeeblement of consciousness howaccounted for--Doubling of consciousness in hysterics--Relations ofphysiological phenomena to consciousness--Consciousness cannot becomeunconscious and yet exist CHAPTER IX DEFINITIONS OF PSYCHOLOGY Difficulty of defining psychology--Definition by substance--Psychology notthe science of the soul--Definition by enumeration: its error--Definitionby method contradicts idea of consciousness--Externospection andintrospection sometimes confused--Definition by content--Facts cannot bedivided into those of consciousness and of unconsciousness--Descartes'definition of psychology insufficient--"Within and without" simileunanalogous--Definition by point of view--Inconsistencies of Ebbinghaus'contention--W. James' teleological theory--Definition by the peculiarnature of mental laws only one possible: why? BOOK III THE UNION OF THE SOUL AND THE BODY CHAPTER I THE MIND HAS AN INCOMPLETE LIFE Problem of union of mind and body stated--Axiom of heterogeneity mustbe rejected--Phenomena of consciousness incomplete--Aristotle's_relatum_ and _correlatum_ applied to the terms mind and matter CHAPTER II SPIRITUALISM AND IDEALISM Spiritualist view that death cuts link between soul andbody--Explanation of link fatal to system--Consciousness cannotexercise functions without objects of cognition--Idealism akaleidoscopic system--Four affirmations of idealism: theirinconsistency--Advantages of historical method CHAPTER III MATERIALISM AND PARALLELISM Materialism oldest doctrine of all: many patristic authors leantowards it--Modern form of, receives impulse from advance of physicalscience--Karl Vogt's comparison of secretions of brain with that ofkidneys--All materialist doctrines opposed to principle ofheterogeneity--Modern materialism would make object generateconsciousness--Materialists cannot demonstrate how molecularvibrations can be transformed into objects--Parallelism avoids issueby declaring mind to be function of brain--Parallelists declarephysical and psychical life to be two parallel currents--Bain'ssupport of this--Objections to: most important that it postulatesconsciousness as a complete whole CHAPTER IV MODERN THEORIES Berkeley's idealism revived by Bergson, though with differentstandpoint--Admirable nature of Bergson's exposition--Fallacy of, partassigned to sensory nerves--Conscious sensations must be subsequent toexcitement of sensory nerves and dependent on their integrity CHAPTER V CONCLUSION Author's own theory only a hypothesis--Important conditions forsolution of problem--Manifestations of consciousness conditioned bybrain, but this last unconscious--Consciousness perceives onlyexternal object--Specificity of nerves not absolute--Why repeatedexcitements of nerve tend to become unconscious--Formation of habitand "instinct"--Resemblance to and distinction of this fromparallelism--Advantages of new theory CHAPTER VI RECAPITULATION Description of matter--Definition of mind--Objections to, answered--Incomplete existence of mind--Other theories--Nervous systemmust add its own effect to that of its excitant BOOK I THE DEFINITION OF MATTER THE MIND AND THE BRAIN[1] CHAPTER I INTRODUCTION This book is a prolonged effort to establish a distinction betweenwhat is called mind and what is called matter. Nothing is more simplethan to realise this distinction when you do not go deeply into it;nothing is more difficult when you analyse it a little. At firstsight, it seems impossible to confuse things so far apart as a thoughtand a block of stone; but on reflection this great contrast vanishes, and other differences have to be sought which are less apparent and ofwhich one has not hitherto dreamed. First let us say how the question presents itself to us. The factwhich we must take as a starting point, for it is independent ofevery kind of theory, is that there exists something which is"knowable. " Not only science, but ordinary life and our everydayconversation, imply that there are things that we know. It is withregard to these things that we have to ask ourselves if some belong towhat we call the mind and others to what we call matter. Let us suppose, by way of hypothesis, the knowable to be entirely andabsolutely homogeneous. In that case we should be obliged to set asidethe question as one already decided. Where everything is homogeneous, there is no distinction to be drawn. But this hypothesis is, as we allknow, falsified by observation. The whole body of the knowable isformed from an agglomeration of extremely varied elements, amongstwhich it is easy to distinguish a large number of divisions. Thingsmay be classified according to their colour, their shape, theirweight, the pleasure they give us, their quality of being alive ordead, and so on; one much given to classification would only betroubled by the number of possible distinctions. Since so many divisions are possible, at which shall we stop and say:this is the one which corresponds exactly to the opposition of mindand matter? The choice is not easy to make; for we shall see thatcertain authors put the distinction between the physical and themental in one thing, others in another. Thus there have been a verylarge number of distinctions proposed, and their number is muchgreater than is generally thought. Since we propose to make ourselvesjudges of these distinctions, since, in fact, we shall reject most ofthem in order to suggest entirely new ones, it must be supposed thatwe shall do so by means of a criterion. Otherwise, we should only beacting fantastically. We should be saying peremptorily, "In my opinionthis is mental, " and there would be no more ground for discussionthan, if the assertion were "I prefer the Romanticists to theClassicists, " or "I consider prose superior to poetry. " The criterion which I have employed, and which I did not analyse untilthe unconscious use I had made of it revealed its existence to me, isbased on the two following rules:-- 1. _A Rule of Method. _--The distinction between mind and matter mustnot only apply to the whole of the knowable, but must be the deepestwhich can divide the knowable, and must further be one of a permanentcharacter. _A priori_, there is nothing to prove the existence of sucha distinction; it must be sought for and, when found, closelyexamined. 2. _An Indication of the Direction in which the Search must beMade. _--Taking into account the position already taken up by themajority of philosophers, the manifestation of mind, if it exists, must be looked for in the domain of facts dealt with by psychology, and the manifestation of matter in the domain explored by physicists. I do not conceal from myself that there may be much that is arbitraryin my own criterion; but this does not seem to me possible to avoid. We must therefore appeal to psychology, and ask whether it iscognisant of any phenomenon offering a violent, lasting, andineffaceable contrast with all the rest of the knowable. _The Method of Concepts and the Method of Enumeration. _--Many authorsare already engaged in this research, and employ a method which Iconsider very bad and very dangerous--the method of concepts. Thisconsists in looking at real and concrete phenomena in their mostabstract form. For example, in studying the mind, they use this word"mind" as a general idea which is supposed to contain all thecharacteristics of psychical phenomena; but they do not wait toenumerate these characteristics or to realise them, and they remainsatisfied with the extremely vague idea springing from an unanalysedconcept. Consequently they use the word "mind" with the imprudence ofa banker who should discount a trade bill without ascertainingwhether the payment of that particular piece of paper had beenprovided for. This amounts to saying that the discussion ofphilosophical problems takes especially a verbal aspect; and the morecomplex the phenomena a concept thus handled, contains, the moredangerous it is. A concept of the colour red has but a very simplecontent, and by using it, this content can be very clearlyrepresented. But how can the immense meaning of the word "mind" berealised every time that it is used? For example, to define mind andto separate it from the rest of the knowable which is called matter, the general mode of reasoning is as follows: all the knowable which isapparent to our senses is essentially reduced to motion; "mind, " thatsomething which lives, feels, and judges, is reduced to "thought. " Tounderstand the difference between matter and mind, it is necessary toask one's self whether there exists any analogy in nature betweenmotion and thought. Now this analogy does not exist, and what wecomprehend, on the contrary, is their absolute opposition. Thought isnot a movement, and has nothing in common with a movement. A movementis never anything else but a displacement, a transfer, a change ofplace undergone by a particle of matter. What relation of similarityexists between this geometrical fact and a desire, an emotion, asensation of bitterness? Far from being identical, these two factsare as distinct as any facts can be, and their distinction is so deepthat it should be raised to the height of a principle, the principleof heterogeneity. This is almost exactly the reasoning that numbers of philosophers haverepeated for several years without giving proof of much originality. This is what I term the metaphysics of concept, for it is aspeculation which consists in juggling with abstract ideas. The momentthat a philosopher opposes thought to movement, I ask myself underwhat form he can think of a "thought, " I suppose he must verypoetically and very vaguely represent to himself something light andsubtle which contrasts with the weight and grossness of materialbodies. And thus our philosopher is punished in the sinning part; hiscontempt of the earthly has led him into an abuse of abstractreasoning, and this abuse has made him the dupe of a very naïvephysical metaphor. At bottom I have not much faith in the nobility of many of ourabstract ideas. In a former psychological study[2] I have shown thatmany of our abstractions are nothing else than embryonic, and, aboveall, loosely defined concrete ideas, which can satisfy only anindolent mind, and are, consequently, full of snares. The opposition between mind and matter appears to me to assume a verydifferent meaning if, instead of repeating ready-made formulas andwasting time on the game of setting concept against concept, we takethe trouble to return to the study of nature, and begin by drawing upan inventory of the respective phenomena of mind and matter, examiningwith each of these phenomena the characteristics in which thefirst-named differ from the second. It is this last method, more slowbut more sure than the other, that we shall follow; and we willcommence by the study of matter. FOOTNOTES: [Footnote 1: _L'Ame et la Corps. _--Disagreeable as it is to alter anauthor's title, the words "Soul and Body" had to be abandoned becauseof their different connotation in English. The title "Mind and Body"was also preoccupied by Bain's work of that name in this series. Thetitle chosen has M. Binet's approval. --ED. ] [Footnote 2: _Étude experímentale de l'Intelligence. _ Paris:Schleicher. ] CHAPTER II OUR KNOWLEDGE OF EXTERNAL OBJECTS IS ONLY SENSATIONS Of late years numerous studies have been published on the conceptionof matter, especially by physicists, chemists, and mathematicians. Among these recent contributions to science I will quote the articlesof Duhem on the Evolution of Mechanics published in 1903 in the _Revuegénérale des Sciences_, and other articles by the same author, in1904, in the _Revue de Philosophie_. Duhem's views have attracted muchattention, and have dealt a serious blow at the whole theory of themechanics of matter. Let me also quote that excellent work of Dastre, _La Vie et la Mort_, wherein the author makes so interesting anapplication to biology of the new theories on energetics; thediscussion between Ostwald and Brillouin on matter, in which two rivalconceptions find themselves engaged in a veritable hand-to-handstruggle (_Revue générale des Sciences_, Nov. And Dec. 1895); thecurious work of Dantec on _les Lois Naturelles_, in which the authoringeniously points out the different sensorial districts into whichscience is divided, although, through a defect in logic, he acceptsmechanics as the final explanation of things. And last, it isimpossible to pass over, in silence, the rare works of Lord Kelvin, sofull, for French readers, of unexpected suggestions, for they show usthe entirely practical and empirical value which the English attach tomechanical models. My object is not to go through these great studies in detail. It isthe part of mathematical and physical philosophers to develop theirideas on the inmost nature of matter, while seeking to establishtheories capable of giving a satisfactory explanation of physicalphenomena. This is the point of view they take up by preference, andno doubt they are right in so doing. The proper rôle of the naturalsciences is to look at phenomena taken by themselves and apart fromthe observer. My own intention, in setting forth these same theories on matter, isto give prominence to a totally different point of view. Instead ofconsidering physical phenomena in themselves, we shall seek to knowwhat idea one ought to form of their nature when one takes intoaccount that they are observed phenomena. While the physicistwithdraws from consideration the part of the observer in theverification of physical phenomena, our rôle is to renounce thisabstraction, to re-establish things in their original complexity, andto ascertain in what the conception of matter consists when it isborne in mind that all material phenomena are known only in theirrelation to ourselves, to our bodies, our nerves, and ourintelligence. This at once leads us to follow, in the exposition of the facts, anorder which the physicist abandons. Since we seek to know what is thephysical phenomenon we perceive, we must first enunciate thisproposition, which will govern the whole of our discussion: to wit-- _Of the outer world we know nothing except our sensations. _ Before demonstrating this proposition, let us develop it by an examplewhich will at least give us some idea of its import. Let us take asexample one of those investigations in which, with the least possiblerecourse to reasoning, the most perfected processes of observation areemployed, and in which one imagines that one is penetrating almostinto the very heart of nature. We are, let us suppose, dissecting ananimal. After killing it, we lay bare its viscera, examine theircolour, form, dimensions, and connections; then we dissect the organsin order to ascertain their internal nature, their texture, structure, and function; then, not content with ocular anatomy, we have recourseto the perfected processes of histology: we take a fragment of thetissues weighing a few milligrammes, we fix it, we mount it, we makeit into strips of no more than a thousandth of a millimetre thick, wecolour it and place it under the microscope, we examine it with themost powerful lenses, we sketch it, and we explain it. All this workof complicated and refined observation, sometimes lasting months andyears, results in a monograph containing minute descriptions oforgans, of cells, and of intra-cellular structures, the wholerepresented and defined in words and pictures. Now, these descriptionsand drawings are the display of the various sensations which thezoologist has experienced in the course of his labours; to thosesensations are added the very numerous interpretations derived fromthe memory, reasoning, and often, also, from the imagination on thepart of the scholar, the last a source at once of errors and ofdiscoveries. But everything properly experimental in the work of thezoologist proceeds from the sensations he has felt or might have felt, and in the particular case treated of, these sensations are almostsolely visual. This observation might be repeated with regard to all objects of theouter world which enter into relation with us. Whether the knowledgeof them be of the common-place or of a scientific order matterslittle. Sensation is its limit, and all objects are known to us bythe sensations they produce in us, and are known to us solely in thismanner. A landscape is nothing but a cluster of sensations. Theoutward form of a body is simply sensation; and the innermost and mostdelicate material structure, the last visible elements of a cell, forexample, are all, in so far as we observe them with the microscope, nothing but sensation. This being understood, the question is, why we have justadmitted--with the majority of authors--that we cannot really know asingle object as it is in itself, and in its own nature, otherwisethan by the intermediary of the sensations it provokes in us? Thiscomes back to saying that we here require explanations on the twofollowing points: why do we admit that we do not really perceive theobjects, but only something intermediate between them and us; and whydo we call this something intermediate a sensation? On this secondpoint I will offer, for the time being, one simple remark: we use theterm sensation for lack of any other to express the intermediatecharacter of our perception of objects; and this use does not, on ourpart, imply any hypothesis. Especially do we leave completely insuspense the question whether sensation is a material phenomenon or astate of being of the mind. These are questions we will deal withlater. For the present it must be understood that the word sensationis simply a term for the something intermediate between the object andour faculty of cognition. [3] We have, therefore, simply to state whywe have admitted that the external perception of objects is producedmediately or by procuration. There are a few philosophers, and those not of the lowest rank, who havethought that this intermediate character of all perception was soevident that there was no need to insist further upon it. John StuartMill, who was certainly and perhaps more than anything a carefullogician, commences an exposition of the idealist thesis to which he wasso much attached, by carelessly saying: "It goes without saying thatobjects are known to us through the intermediary of our senses. .. . Thesenses are equivalent to our sensations;"[4] and on those propositionshe rears his whole system, "It goes without saying . .. " is a triflethoughtless. I certainly think he was wrong in not testing morecarefully the solidity of his starting point. In the first place, this limit set to our knowledge of the objectswhich stimulate our sensations is only accepted without difficulty bywell-informed persons; it much astonishes the uninstructed when firstexplained to them. And this astonishment, although it may seem so, isnot a point that can be neglected, for it proves that, in the firstand simple state of our knowledge, we believe we directly perceiveobjects as they are. Now, if we, the cultured class, have, for themost part, [5] abandoned this primitive belief, we have only done so oncertain implicit conditions, of which we must take cognisance. This iswhat I shall now demonstrate as clearly as I can. Take the case of an unlearned person. To prove to him that he knowssensations alone and not the bodies which excite them, a very strikingargument may be employed which requires no subtle reasoning and whichappeals to his observation. This is to inform him, supposing he is notaware of the fact, that, every time he has the perception of anexterior object, there is something interposed between the object andhimself, and that that something is his nervous system. If we were not acquainted with the existence of our nervous system, weshould unhesitatingly admit that our perception of objects consistedin some sort of motion towards the places in which they were fixed. Now, a number of experiments prove to us that objects are known to usas excitants of our nervous system which only act on this system byentering into communication, or coming into contact with, its terminalextremities. They then produce, in the interior of this system, apeculiar modification which we are not yet able to define. It is thismodification which follows the course of the nerves and is carried tothe central parts of the system. The speed of the propagation of thisnerve modification has been measured by certain precise experiments inpsychometry; the journey is made slowly, at the rate of 20 to 30metres per second, and it is of interest that this rate of speed letsus know at what moment and, consequently, by what organic excitement, the phenomenon of consciousness is produced. This happens when thecerebral centres are affected; the phenomenon of consciousness istherefore posterior to the fact of the physical excitement. I believe it has required a long series of accepted observations forus to have arrived at this idea, now so natural in appearance, thatthe modifications produced within our nervous system are the onlystates of which we can have a direct consciousness; and asexperimental demonstration is always limited, there can be no absolutecertainty that things never happen otherwise, that we never go outsideourselves, and that neither our consciousness nor our nervous influxcan exteriorise itself, shoot beyond our material organs, and travelafar in pursuit of objects in order to know or to modify them. * * * * * Before going further, we must make our terminology more precise. Wehave just seen the necessity of drawing a distinction between thesensations of which we are conscious and the unknown cause whichproduces these sensations by acting on our nervous systems. Thisexciting cause I have several times termed, in order to be understood, the external object. But under the name of external object arecurrently designated groups of sensations, such as those which make upfor us a chair, a tree, an animal, or any kind of body. I see a dogpass in the street. I call this dog an external object; but, as thisdog is formed, for me who am looking at it, of my sensations, and asthese sensations are states of my nervous centres, it happens that theterm external object has two meanings. Sometimes it designates oursensations; at another, the exciting cause of our sensations. To avoidall confusion we will call this exciting cause, which is unknown tous, the _X_ of matter. It is, however, not entirely unknown, for we at least know two factswith regard to it. We know, first, that this _X_ exists, and in thesecond place, that its image must not be sought in the sensations itexcites in us. How can we doubt, we say, that it exists? The sameexternal observation proves to us at once that there exists an objectdistinct from our nerves, and that our nerves separate us from it. Iinsist on this point, for the reason that some authors, after havingunreservedly admitted that our knowledge is confined to sensations, have subsequently been hard put to it to demonstrate the reality ofthe excitant distinct from the sensations. [6] Of this we need nodemonstration, and the testimony of our senses suffices. We have seenthe excitant, and it is like a friend who should pass before us indisguise so well costumed and made up that we can attribute to hisreal self nothing of what we see of him, but yet we know that it ishe. And, in fact, let us remember what it is that we have arguedupon--viz. On an observation. I look at my hand, and I see an objectapproaching it which gives me a sensation of feeling. I at first saythat this object is an excitant. It is pointed out to me that I am inerror. This object, which appears to me outside my nervous system, iscomposed, I am told, of sensations. Be it so, I have the right toanswer; but if all that I perceive is sensation, my nervous systemitself is a sensation; if it is only that, it is no longer anintermediary between the excitant and myself, and it is the fact thatwe perceive things as they are. For it to be possible to prove that Iperceive, not the object, but that _tertium quid_ which is sensation, it has to be admitted that the nervous system is a reality external tosensation and that objects which assume, in relation to it, the rôleof excitants and of which we perceive the existence, are likewiserealities external to sensation. This is what is demonstrated by abstract reasoning, and this reasoningis further supported by a common-sense argument. The outer worldcannot be summarised in a few nervous systems suspended like spidersin empty space. The existence of a nervous system implies that of abody in which it is lodged. This body must have complicated organs;its limbs presuppose the soil on which the animal rests, its lungs theexistence of oxygen vivifying its blood, its digestive tube, alimentswhich it digests and assimilates to its substance, and so on. We mayindeed admit that this outer world is not, in itself, exactly as weperceive it; but we are compelled to recognise that it exists by thesame right as the nervous system, in order to put it in its properplace. The second fact of observation is that the sensations we feel do notgive us the true image of the material _X_ which produces them. Themodification made in our substance by this force _X_ does notnecessarily resemble in its nature the nature of that force. This isan assertion opposed to our natural opinions, and must consequently bedemonstrated. It is generally proved by the experiments which revealwhat is called "the law of the specific energy of the nerves. " This isan important law in physiology discovered by Müller two centuries ago, and consequences of a philosophical order are attached to it. Thefacts on which this law is based are these. It is observed that, ifthe sensory nerves are agitated by an excitant which remains constant, the sensations received by the patient differ according to the nerveaffected. Thus, the terminals of an electric current applied to theball of the eye give the sensation of a small luminous spark; to theauditory apparatus, the current causes a crackling sound; to the hand, the sensation of a shock; to the tongue, a metallic flavour. Conversely, excitants wholly different, but affecting the same nerve, give similar sensations; whether a ray of light is projected into theeye, or the eyeball be excited by the pressure of a finger; whether anelectric current is directed into the eye, or, by a surgicaloperation, the optic nerve is severed by a bistoury, the effect isalways the same, in the sense that the patient always receives asensation of light. To sum up, in addition to the natural excitant ofour sensory nerves, there are two which can produce the same sensoryeffects, that is to say, the mechanical and the electrical excitants. Whence it has been concluded that the peculiar nature of the sensationfelt depends much less on the nature of the excitant producing it thanon that of the sensory organ which collects it, the nerve whichpropagates it, or the centre which receives it. It would perhaps begoing a little too far to affirm that the external object has no kindof resemblance to the sensations it gives us. It is safer to say thatwe are ignorant of the degree in which the two resemble or differ fromeach other. On thinking it over, it will be found that this contains a very greatmystery, for this power of distinction (_specificité_) of our nervesis not connected with any detail observable in their structure. It isvery probably the receiving centres which are specific. It is owing tothem and to their mechanism that we ought to feel, from the sameexcitant, a sensation of sound or one of colour, that is to say, impressions which appear, when compared, as the most different in theworld. Now, so far as we can make out, the histological structure ofour auditory centre is the same as that of our visual centre. Both area collection of cells diverse in form, multipolar, and maintained bya conjunctive pellicule (_stroma_). The structure of the fibres andcells varies slightly in the motor and sensory regions, but no meanshave yet been discovered of perceiving a settled difference betweenthe nerve-cells of the optic centre and those of the auditory centre. There should be a difference, as our mind demands it; but our eyefails to note it. Let us suppose, however, that to-morrow, or several centuries hence, an improved _technique_ should show us a material difference betweenthe visual and the auditory neurone. There is no absurdity in thissupposition; it is a possible discovery, since it is of the order ofmaterial facts. Such a discovery, however, would lead us very far, forwhat terribly complicates this problem is that we cannot directly knowthe structure of our nervous system. Though close to us, though, so tospeak, inside us, it is not known to us otherwise than is the objectwe hold in our hands, the ground we tread, or the landscape whichforms our horizon. For us it is but a sensation, a real sensation when we observe it inthe dissection of an animal, or the autopsy of one of our own kind; animaginary and transposed sensation, when we are studying anatomy bymeans of an anatomical chart; but still a sensation. It is by theintermediary of our nervous system that we have to perceive andimagine what a nervous system is like; consequently we are ignorant asto the modification impressed on our perceptions and imaginations bythis intermediary, the nature of which we are unable to grasp. Therefore, when we attempt to understand the inmost nature of theouter world, we stand before it as before absolute darkness. Thereprobably exists in nature, outside of ourselves, neither colour, odour, force, resistance, space, nor anything that we know assensation. Light is produced by the excitement of the optic nerve, andit shines only in our brain; as to the excitement itself, there isnothing to prove that it is luminous; outside of us is profounddarkness, or even worse, since darkness is the correlation of light. In the same way, all the sonorous excitements which assail us, thecreakings of machines, the sounds of nature, the words and cries ofour fellows are produced by excitements of our acoustic nerve; it isin our brain that noise is produced, outside there reigns a deadsilence. The same may be said of all our other senses. Not one of our senses, absolutely none, is the revealer of externalreality. From this point of view there is no higher and no lowersense. The sensations of sight, apparently so objective and sosearching, no more take us out of ourselves than do the sensations oftaste which are localised in the tongue. In short, our nervous system, which enables us to communicate withobjects, prevents us, on the other hand, from knowing their nature. Itis an organ of relation with the outer world; it is also, for us, acause of isolation. We never go outside ourselves. We are walled in. And all we can say of matter and of the outer world is, that it isrevealed to us solely by the sensations it affords us, that it is theunknown cause of our sensations, the inaccessible excitant of ourorgans of the senses, and that the ideas we are able to form as to thenature and the properties of that excitant, are necessarily derivedfrom our sensations, and are subjective to the same degree as thosesensations themselves. But we must make haste to add that this point of view is the one whichis reached when we regard the relations of sensation with its unknowncause the great _X_ of matter. [7] Positive science and practical lifedo not take for an objective this relation of sensation with theUnknowable; they leave this to metaphysics. They distribute themselvesover the study of sensation and examine the reciprocal relations ofsensations with sensations. Those last, condemned as misleadingappearances when we seek in them the expression of the Unknowable, lose this illusory character when we consider them in their reciprocalrelations. Then they constitute for us reality, the whole of realityand the only object of human knowledge. The world is but an assemblyof present, past, and possible sensations; the affair of science is toanalyse and co-ordinate them by separating their accidental from theirconstant relations. FOOTNOTES: [Footnote 3: _Connaissance. _--The word cognition is used throughout asthe English equivalent of this, except in places where the contextshows that it means acquaintance merely. --ED. ] [Footnote 4: J. S. MILL, _An Examination of Sir Wm. Hamilton'sPhilosophy_, pp. 5 and 6. London. 1865. ] [Footnote 5: A few subtle philosophers have returned to it, as I shallshow later in chapter iv. ] [Footnote 6: Thus, the perplexity in which John Stuart Mill findshimself is very curious. Having admitted unreservedly that ourknowledge is confined to sensations, he is powerless to set up areality outside this, and acknowledges that the principle of causalitycannot legitimately be used to prove that our sensations have a causewhich is not a sensation, because this principle cannot be appliedoutside the world of phenomena. ] [Footnote 7: See p. 18, _sup_. --ED. ] CHAPTER III THE MECHANICAL THEORIES OF MATTER ARE ONLY SYMBOLS If we keep firmly in mind the preceding conclusion--a conclusion whichis neither exclusively my own, nor very new--we shall find a certainsatisfaction in watching the discussions of physicists on the essenceof matter, on the nature of force and of energy, and on the relationsof ponderable and imponderable matter. We all know how hot is thefight raging on this question. At the present time it is increasing inintensity, in consequence of the disturbance imported into existingtheories by the new discoveries of radio-activity. [8] We psychologistscan look on very calmly at these discussions, with that selfishpleasure we unavowedly feel when we see people fighting whileourselves safe from knocks. We have, in fact, the feeling that, comewhat may from the discussions on the essence of matter, there can beno going beyond the truth that matter is an excitant of our nervoussystem, and is only known in connection with, the perception we haveof this last. If we open a work on physics or physiology we shall note withastonishment how the above considerations are misunderstood. Observersof nature who seek, and rightly, to give the maximum of exactness totheir observations, show that they are obsessed by one constantprejudice: they mistrust sensation. A great part of their efforts consists, by what they say, in reducingthe rôle of sensation to its fitting part in science; and theinvention of mechanical aids to observation is constantly held up as ameans of remedying the imperfection of our senses. In physics thethermometer replaces the sensation of heat that our skin--our hand, for example--experiences by the measurable elevation of a column ofmercury, and the scale-pan of a precise balance takes the place of thevague sensation of trifling weights; in physiology a registeringapparatus replaces the sensation of the pulse which the doctor feelswith the end of his forefinger by a line on paper traced withindelible ink, of which the duration and the intensity, as well as thevaried combinations of these two elements, can be measured line byline. Learned men who pride themselves on their philosophical attainmentsvaunt in very eloquent words the superiority of the physicalinstrument over mere sensation. Evidently, however, the earnestness ofthis eulogy leads them astray. The most perfect registering apparatusmust, in the long-run, after its most scientific operations, addressitself to our senses and produce in us some small sensation. Thereading of the height reached by the column of mercury in athermometer when heated is accomplished by a visual sensation, and itis by the sight that the movements of the balance are controlled; andthat the traces of the sphygmograph are analysed. We may readily admitto physicists and physiologists all the advantages of these apparatus. This is not the question. It simply proves that there are sensationsand sensations, and that certain of these are better and more precisethan others. The visual sensation of relation in space seems to be_par excellence_ the scientific sensation which it is sought tosubstitute for all the rest. But, after all, it is but a sensation. Let us recognise that there is, in all this contempt on the part ofphysicists for sensation, only differences in language, and that aparaphrase would suffice to correct them without leaving any trace. Beit so. But something graver remains. When one is convinced that ourknowledge of the outer world is limited to sensations, we can nolonger understand how it is possible to give oneself up, as physicistsdo, to speculations upon the constitution of matter. Up to the present there have been three principal ways of explainingthe physical phenomena of the universe. The first, the most abstract, and the furthest from reality, is above all verbal. It consists in theuse of formulas in which the quality of the phenomena is replaced bytheir magnitude, in which this magnitude, ascertained by the mostprecise processes of measurement, becomes the object of abstractreasoning which allows its modifications to be foreseen under givenexperimental conditions. This is pure mathematics, a formal sciencedepending upon logic. Another conception, less restricted than theabove, and of fairly recent date, consists in treating allmanifestations of nature as forms of energy. This term "energy" has avery vague content. At the most it expresses but two things: first, itis based on a faint recollection of muscular force, and it reminds onedimly of the sensation experienced when clenching the fists; and, secondly, it betrays a kind of very natural respect for the forces ofnature which, in all the images man has made of them, constantlyappear superior to his own. We may say "the energy of nature;" but weshould never say, what would be experimentally correct; "the weaknessof nature. " The word "weakness" we reserve for ourselves. Apart fromthese undecided suggestions, the term energy is quite the proper termto designate phenomena, the intimate nature of which we do not seek topenetrate, but of which we only wish to ascertain the laws and measurethe degrees. A third conception, more imaginative and bolder than the others, isthe mechanical or kinetic theory. This last absolutely desires that weshould represent to ourselves, that we should imagine, how phenomenareally take place; and in seeking for the property of nature the mostclearly perceived, the easiest to define and analyse, and the most aptto lend itself to measurement and calculation, it has chosen motion. Consequently all the properties of matter have been reduced to thisone, and in spite of the apparent contradiction of our senses, it hasbeen supposed that the most varied phenomena are produced, in the lastresort, by the displacement of material particles. Thus, sound, light, heat, electricity, and even the nervous influx would be due tovibratory movements, varying only by their direction and theirperiods, and all nature is thus explained as a problem of animatedgeometry. This last theory, which has proved very fertile inexplanations of the most delicate phenomena of sound and light, has sostrongly impressed many minds that it has led them to declare thatthe explanation of phenomena by the laws of mechanics alone has thecharacter of a scientific explanation. Even recently, it seemed heresyto combat these ideas. Still more recently, however, a revulsion of opinion has taken place. Against the physicists, the mathematicians in particular have risenup, and taking their stand on science, have demonstrated that all themechanisms invented have crowds of defects. First, in each particularcase, there is such a complication that that which is defined is muchmore simple than the definition; then there is such a want of unitythat quite special mechanisms adapted to each phenomenal detail haveto be imagined; and, lastly--most serious argument of all--so muchcomprehensiveness and suppleness is employed, that no experimental lawis found which cannot be understood mechanically, and no fact ofobservation which shows an error in the mechanical explanation--a sureproof that this mode of explanation has no meaning. My way of combating the mechanical theory starts from a totallydifferent point of view. Psychology has every right to say a few wordshere, as upon the value of every kind of scientific theory; for it isacquainted with the nature of the mental needs of which these theoriesare the expression and which these theories seek to satisfy. It hasnot yet been sufficiently noticed that psychology does not allowitself to be confined, like physics or sociology, within the logicaltable of human knowledge, for it has, by a unique privilege, a rightof supervision over the other sciences. We shall see that thepsychological discussion of mechanics has a wider range than that ofthe mathematicians. Since our cognition cannot go beyond sensation, shall we first recallwhat meaning can be given to an explanation of the inmost nature ofmatter? It can only be an artifice, a symbol, or a process convenientfor classification in order to combine the very different qualities ofthings in one unifying synthesis--a process having nearly the sametheoretical value as a _memoria technica_, which, by substitutingletters for figures, helps us to retain the latter in our minds. Thisdoes not mean that figures are, in fact, letters, but it is aconventional substitution which has a practical advantage. What_memoria technica_ is to the ordinary memory, the theory of mechanicsshould be for our needed unification. Unfortunately, this is not so. The excuse we are trying to make forthe mechanicians is illusory. There is no mistaking their ambition, Notwithstanding the prudence of some and the equivocations in whichothers have rejoiced, they have drawn their definition in the absoluteand not in the relative. To take their conceptions literally, theyhave thought the movement of matter to be something existing outsideour eye, our hands, and our sense; in a word, something _noumenal_, asKant would have said. The proof that this is their real idea, is thatmovement is presented to us as the true outer and explanatory cause ofour sensations, the external excitement to our nerves. The mostelementary works on physics are impregnated with this disconcertingconception. If we open a description of acoustics, we read that soundand noise are subjective states which have no reality outside ourauditory apparatus; that they are sensations produced by an externalcause, which is the vibratory movement of sonorous bodies--whence theconclusion that this vibratory movement is not itself a sensation. Or, shall we take another proof, still more convincing. This is thevibratory and silent movement which is invoked by physicists toexplain the peculiarities of subjective sensation; so that theinterferences, the pulsations of sound, and, in fine, the wholephysiology of the ear, is treated as a problem in kinematics, and isexplained by the composition of movements. What kind of reality do physicists then allow to the displacements ofmatter? Where do they place them, since they recognise otherwise thatthe essence of matter is unknown to us? Are we to suppose that, outside the world of _noumena_, outside the world of phenomena andsensations, there exists a third world, an intermediary between thetwo former, the world of atoms and that of mechanics? A short examination will, moreover, suffice to show of what thismechanical model is formed which is presented to us as constitutingthe essence of matter. This can be nothing else than the sensations, since we are incapable of perceiving or imagining anything else. It isthe sensations of sight, of touch, and even of the muscular sense. Motion is a fact seen by the eye, felt by the hand; it enters into usby the perception we have of the solid masses visible to the naked eyewhich exist in our field of observation, of their movements and theirequilibrium and the displacement we ourselves effect with our bodies. Here is the sensory origin, very humble and very gross, of all themechanics of the atoms. Here is the stuff of which our loftyconception is formed. Our mind can, it is true, by a work ofpurification, strip movement of most of its concrete qualities, separate it even from the perception of the object in motion, and makeof it a something or other ideal and diagrammatic; but there willstill remain a residuum of visual, tactile, and muscular sensations, and consequently it is still nothing else than a subjective state, bound to the structure of our organs. We are, for the rest, sowrapped up in sensations that none of our boldest conceptions canbreak through the circle. But it is not the notion of movement alone which proceeds fromsensation. There is also that of exteriority, of space, of position, and, by opposition, that of external or psychological events. Withoutdeclaring it to be certain, I will remind you that it is infinitelyprobable that these notions are derived from our muscular experience. Free motion, arrested motion, the effort, the speed, and the directionof motion, such are the sensorial elements, which, in all probability, constitute the foundation of our ideas on space and its properties. And those are so many subjective notions which we have no right totreat as objects belonging to the outer world. What is more remarkable, also, is that even the ideas of object, ofbody, and of matter, are derived from visual and tactile sensationswhich have been illegitimately set up as entities. We have come, infact, to consider matter as a being separate from sensations, superiorto our sensations, distinct from the properties which enable us toknow it, and binding together these properties, as it were, in asheaf. Here again is a conception at the base of visualisation andmuscularisation; it consists in referring to the visual and othersensations, raised for the occasion to the dignity of external andpermanent causes, the other sensations which are considered as theeffects of the first named upon our organs of sense. It demands a great effort to clear our minds of these familiarconceptions which, it is plain are nothing but naïve realism. Yes! themechanical conception of the universe is nothing but naïve realism. To recapitulate our idea, and, to make it more plain by anillustration, here is a tuning-fork on the table before me. With avigorous stroke of the bow I set it vibrating. The two prongsseparate, oscillate rapidly, and a sound of a certain tone is heard. Iconnect this tuning-fork, by means of electric wires, with a Déprezrecording apparatus which records the vibrations on the blackenedsurface of a revolving cylinder; and we can thus, by an examination ofthe trace made under our eyes, ascertain all the details of themovement which animates it. We see, parallel to each other, twodifferent orders of phenomena; the visual phenomena which show us thatthe tuning-fork is vibrating, and the auditory phenomena which conveyto us the fact that it is making a sound. The physicist, asked for an explanation of all this, will answer: "Itis the vibration of the tuning-fork which, transmitted by the air, iscarried to our auditory apparatus, causes a vibration in thetympanum, the movements of which are communicated to the small bonesof the middle ear, thence (abridging details) to the terminations ofthe auditory nerve, and so produces in us the subjective sensation ofsound. " Well, in so saying, the physicist commits an error ofinterpretation; outside our ears there exists something we do not knowwhich excites them; this something cannot be the vibratory movement ofthe tuning-fork, for this vibratory movement which we can see islikewise a subjective sensation; it no more exists outside our sightthan sound exists outside our ears. In any case, it is as absurd toexplain a sensation of sound by one of sight, as a sensation of sightby one of sound. One would be neither further from nor nearer to the truth if weanswered that physicist as follows: "You give the preponderance toyour eye; I myself give it to my ear. This tuning-fork appears to youto vibrate. Wrong! This is how the thing occurs. This tuning-forkproduces a sound which, by exciting our retina, gives us a sense ofmovement. This visual sensation of vibration is a purely subjectiveone, the external cause of the phenomenon is the sound. The outerworld is a concert of sounds which rises in the immensity of space. Matter is noise and nothingness is silence. " This theory of the above experiment is not absurd; but, as a matterof fact, it is probable that no one would or could accept it, exceptverbally for amusement, as a challenge, or for the pleasure of talkingmetaphysics. The reason is that all our evolution, for causes whichwould take too long to detail, has established the hegemony of certainof our senses over the others. We have, above all, become visual andmanual beings. It is the eye and the hand which give us theperceptions of the outer world of which we almost exclusively make usein our sciences; and we are now almost incapable of representing toourselves the foundation of phenomena otherwise than by means of theseorgans. Thus all the preceding experiment from the stroke of the bowto the final noise presents itself to us in visual terms, and further, these terms are not confined to a series of detached sensations. Visual sensation combines with the tactile and muscular sensations, and forms sensorial constructions which succeed each, other, continue, and arrange themselves logically: in lieu of sensations, there areobjects and relations of space between these objects, and the actionswhich connect them, and the phenomena which pass from one to theother. All that is only sensation, if you will; but merely as theagglutinated molecules of cement and of stone are a palace. Thus the whole series of visual events which compose our experimentwith the tuning-fork can be coherently explained. One understands thatIt is the movement of my hand equipped with the bow which iscommunicated to the tuning-fork. One understands that this movementpassing into the fork has changed its form and rhythm, that the wavesproduced by the fork transmit themselves, by the oscillations of theair-molecules, to our tympanum, and so on. There is in all this seriesof experiments an admirable continuity which fully satisfies ourminds. However much we might be convinced by the theoretical reasonsgiven above, that we have quite as much right to represent the sameseries of events in an auditory form, we should be incapable ofrealising that form to ourselves. What would be the structure of the ear to any one who only knew itthrough the sense of hearing? What would become of the tympanum, thesmall bones, the cochlea, and the terminations of the acoustic nerve, if it were only permitted to represent them in the language of sound?It is very difficult to imagine. Since, however, we are theorising, let us not be stopped by a fewdifficulties of comprehension. Perhaps a little training might enableus to overcome them. Perhaps musicians, who discern as much reality inwhat one hears as in what one sees, would be more apt than other folkto understand the necessary transposition. Some of them, in theirautobiographies, have made, by the way, very suggestive remarks on theimportance they attribute to sound: and, moreover, the musical world, with its notes, its intervals, and its orchestration, lives anddevelops in a manner totally independent of vibration. Perhaps we can here quote one or two examples which may give us alead. To measure the length of a body instead of applying to it ayard-wand, one might listen to its sound; for the pitch of the soundgiven by two cords allows us to deduce their difference of length, andeven the absolute length of each. The chemical composition of a bodymight be noted by its electric resistance and the latter verified bythe telephone; that is to say, by the ear. Or, to take a more subtleexample. We might make calculations with sounds of which we havestudied the harmonic relations as we do nowadays with figures. A sumin rule of three might even be solved sonorously; for, given threesounds, the ear can find a fourth which should have the same relationto the third as the second to the first. Every musical ear performsthis operation easily; now, this fourth sound, what else is it but thefourth term in a rule of three? And by taking into consideration thenumber of its vibrations a numerical solution would be found to theproblem. This novel form of calculating machine might serve to fixthe price of woollen stuffs, to calculate brokerages and percentages, and the solution would be obtained without the aid of figures, withoutcalculation, without visualisation, and by the ear alone. By following up this idea, also, we might go a little further. Wemight arrive at the conviction that our present science is human, petty, and contingent; that it is closely linked with the structure ofour sensory organs; that this structure results from the evolutionwhich fashioned these organs; that this evolution has been an accidentof history; that in the future it may be different; and that, consequently, by the side or in the stead of our modern science, thework of our eyes and hands--and also of our words--there might havebeen constituted, there may still be constituted, sciences entirelyand extraordinarily new--auditory, olfactory, and gustatory sciences, and even others derived from other kinds of sensations which we canneither foresee nor conceive because they are not, for the moment, differentiated in us. Outside the matter we know, a very specialmatter fashioned of vision and touch, there may exist other matterwith totally different properties. But let us bring our dream to an end. The interest of our discussiondoes not lie in the hypothetical substitution of hearing or any othersense for sight. It lies in the complete suppression of allexplanation of the noumenal object in terms borrowed from the languageof sensation. And that is our last word. We must, by setting aside themechanical theory, free ourselves from a too narrow conception of theconstitution of matter. And this liberation will be to us a greatadvantage which we shall soon reap. We shall avoid the error ofbelieving that mechanics is the only real thing and that all thatcannot be explained by mechanics must be incomprehensible. We shallthen gain more liberty of mind for understanding what the union of thesoul with the body[9] may be. FOOTNOTES: [Footnote 8: I would draw attention to a recent volume by GUSTAVE LEBON, on _Evolution de la Matière_, a work full of original and boldideas. ] [Footnote 9: See [Note 1] on p. 3. --ED. ] CHAPTER IV ANSWERS TO SOME OBJECTIONS, AND SUMMARY I have set forth the foregoing ideas by taking the road which to meseemed the best. On reflection it has occurred to me that my manner ofexposition and demonstration may be criticised much more than myconclusion. Now, as it is the conclusion alone which here is ofimportance, it is expedient not to make it responsible for thearguments by which I have supported it. These arguments resolve themselves into the attestation that betweenobjects and our consciousness there exists an intermediary, ournervous system. We have even established that the existence of thisintermediary is directly proved by observation, and from this I haveconcluded that we do not directly perceive the object itself but a_tertium quid_, which is our sensations. Several objections to this might be made. Let us enumerate them. 1. It is not inconceivable that objects may act directly on ourconsciousness without taking the intermediary of our nervous system. Some authors, the spiritualists notably, believe in the possibilityof disembodied souls, and they admit by implication that these soulsremain in communication with the terrestrial world, witness ouractions, and hear our speech. Since they no longer have organs ofsense, we must suppose that these wandering souls, if they exist, candirectly perceive material objects. It is evident that such hypotheseshave, up till now, nothing scientific in them, and that thedemonstrations of them which are given raise a feeling of scepticismmore than anything else. Nevertheless, we have not the right toexclude, by _a priori_ argument, the possibility of this category ofphenomena. 2. Several German authors have maintained in recent years, that if thenervous system intervenes in the perception of external objects, it isa faithful intermediary which should not work any change on thosephysical actions which it gathers from outside to transmit to ourconsciousness. From this, point of view colour would exist as colour, outside our eyes, sound would exist as sound, and in a general waythere would not be, in matter, any mysterious property left, since weshould perceive matter as it is. This is a very unexpectedinterpretation, by which men of science have come to acknowledge thecorrectness of the common belief: they rehabilitate an opinion whichphilosophers have till now turned to ridicule, under the name ofnaïve realism. All which proves that the naïveté of some may be theexcessive refinement of others. To establish scientifically this opinion they batter down the theoryof the specific energy of the nerves. I have recalled in a previouspage[10] of what this theory consists. I have shown that if, bymechanical or electrical means, our different sensory nerves areexcited, notwithstanding the identity of the excitant, a differentsensation is provoked in each case--light when the optic nerve isstimulated, sound when the acoustic, and so on. It is now answered tothis argument based on fact that the nature of these excitants must becomplex. It is not impossible, it is thought, that the electric forcecontains within itself both luminous and sonorous actions; it is notimpossible that a mechanical excitement should change the electricstate of the nerve affected, and that, consequently, these subsidiaryeffects explain how one and the same agent may, according to thenerves employed, produce different effects. 3. After the spiritualists and the experimentalists, let us take themetaphysicians. Among them one has always met with the most varyingspecimens of opinions and with arguments for and against all possibletheories. Thus it is, for example, with the external perception. Some havesupposed it indirect, others, on the contrary, that it acts directlyon the object. Those who uphold the direct theory are inspired byBerkeley, who asserts that the sensitive qualities of the body have noexistence but in our own minds, and consist really in representativeideas. This doctrine is expressly based on this argument--that thoughtdiffers too much in nature from matter for one to be able to supposeany link between these two substances. In this particular, someauthors often make an assertion without endeavouring to prove it. Theyare satisfied with attesting, or even with supposing, that mind canhave no consciousness of anything but its own states. Otherphilosophers, as I have said, maintain that "things which have a realexistence are the very things we perceive. " It is Thomas Reid who hasupheld, in some passages of his writings at all events, the theory ofinstantaneous perception, or intuition. It has also been defended byHamilton in a more explicit manner. [11] It has been taken up again inrecent years, by a profound and subtle philosopher, M. Bergson, who, unable to admit that the nervous system is a _substratum of knowledge_and serves us as a percipient, takes it to be solely a motor organ, and urges that the sensory parts of the system--that is to say, thecentripetal, optic, acoustic, &c, nerves--do not call forth, whenexcited, any kind of sensation, their sole purpose being to conveydisturbances from periphery to periphery, or, say, from externalobjects to the muscles of the body. This hypothesis, surely a littledifficult to comprehend, places, if I mistake not, the mind, as apower of perception and representation, within the interval comprisedbetween the external object and the body, so that the mind is indirect contact with external objects and knows them as they are. It will be noticed that these three interpretations, thespiritualistic, the experimental, and the metaphysical, are in formalopposition with that which I have set forth earlier in these pages. They deny the supposition that the nervous system serves us as anintermediary with nature, and that it transforms nature beforebringing it to our consciousness. And it might seem that bycontradicting my fundamental proposition, those three new hypothesesmust lead to a totally different conclusion. Now, this is not so at all. The conclusion I have enunciated remainsentirely sound, notwithstanding this change in the starting point, andfor the following reason. It is easy to see that we cannot representto ourselves the inner structure of matter by using all our sensationswithout distinction, because it is impossible to bring all thesesensations within one single and identical synthetic construction: forthis they are too dissimilar. Thus, we should try in vain to unite inany kind of scheme a movement of molecules and an odour; theseelements are so heterogeneous that there is no way of joining themtogether and combining them. The physicists have more or less consciously perceived this, and, notbeing able to overcome by a frontal attack the difficulty created bythe heterogeneity of our sensations, they have turned its flank. Theingenious artifice they have devised consists in retaining only someof these sensations, and in rejecting the remainder; the first beingconsidered as really representing the essence of matter, and thelatter as the effects of the former on our organs of sense; the firstbeing reputed to be true, we may say, and the second being reputedfalse--that is subjective, that is not representing the _X_ ofmatter. [12] I have refuted this argument by showing that all oursensations without exception are subjective and equally false inregard to the _X_ of matter, and that no one of them, consequently, has any claim to explain the others. Now, by a new interpretation; we are taught that all sensations areequally true, and that all faithfully represent the great _X. _ If theybe all equally true, it is absolutely the same as if they were allfalse; no one sensation can have any privilege over the others, nonecan be truer than the others, none can be capable of explaining theothers, none can usurp to itself the sole right of representing theessence of matter; and we thus find ourselves, in this case, as in thepreceding, in presence of the insurmountable difficulty of creating asynthesis with heterogeneous elements. All that has been said above is summed up in the following points:-- 1. Of the external world, we only know our sensations. All thephysical properties of matter resolve themselves for us intosensations, present, past, or possible. We may not say that it is bythe intermediary, by the means of sensation, that we know theseproperties, for that would mean that the properties are distinct fromthe sensations. Objects are to us in reality only aggregates ofsensations. 2. The sensations belong to the different organs of the senses--sight, hearing, touch, the muscular sense, &c. Whatever be the senseaffected, one sensation has the same rights as the others, from thepoint of view of the cognition of external objects. It is impossibleto distinguish them into subjective and objective, by giving to thisdistinction the meaning that certain sensations represent objects asthey are, while certain others simply represent our manner of feeling. This is an illegitimate distinction, since all sensations have thesame physiological condition, the excitement of a sensory nerve, andresult from the properties of this nerve when stimulated. 3. Consequently, it is impossible for us to form a conception ofmatter in terms of movement, and to explain by the modalities ofmovement the properties of bodies; for this theory amounts to givingto certain sensations, especially those of the muscular sense, thehegemony over the others. We cannot explain, we have not the right toexplain, one sensation by another, and the mechanical theory of matterhas simply the value of a symbol. FOOTNOTES: [Footnote 10: See p. 22, _sup. _--ED. ] [Footnote 11: See J. S. MILL'S _Examination of Sir Wm. Hamilton'sPhilosophy_, chap. X. P. 176, _et. Seq. _] [Footnote 12: See p. 18, _sup. _--ED. ] BOOK II THE DEFINITION OF MIND CHAPTER I THE DISTINCTION BETWEEN COGNITION[13] AND ITS OBJECT After having thus studied matter and reduced it to sensations, weshall apply the same method of analysis to mind, and inquire whethermind possesses any characteristic which allows it to be distinguishedfrom matter. Before going any further, let me clear up an ambiguity. All the firstpart of this work has been devoted to the study of what is known to usin and by sensation; and I have taken upon myself, without advancingany kind of justifying reason, to call that which is known to us, bythis method, by the name of matter, thus losing sight of the fact thatmatter only exists by contra-distinction and opposition to mind, andthat if mind did not exist, neither would matter. I have thus appearedto prejudge the question to be resolved. The whole of this terminology must now be considered as having simplya conventional value, and must be set aside for the present. Theseare the precise terms in which this question presents itself to mymind. A part of the knowable consists in sensations. We must, therefore, without troubling to style this aggregate of sensations_matter_ rather than _mind_, make an analysis of the phenomena knownby the name of mind, and see whether they differ from the precedingones. Let us, therefore, make an inventory of mind. By the process ofenumeration, we find quoted as psychological phenomena, thesensations, the perceptions, the ideas, the recollections, thereasonings, the emotions, the desires, the imaginations, and the actsof attention and of will. These appear to be, at the first glance, theelements of mind; but, on reflection, one perceives that theseelements belong to two distinct categories, of which it is easy torecognise the duality, although, in fact and in reality, these twoelements are constantly combined. The first of these elements mayreceive the generic name of objects of cognition, or objects known, and the second that of acts of cognition. Here are a few examples of concrete facts, which only require a rapidanalysis to make their double nature plain. In a sensation which wefeel are two things: a particular state, or an object which one knows, and the act of knowing it, of feeling it, of taking cognisance of it;in other words, every sensation comprises an impression and acognition. In a recollection there is, in like manner, a certain imageof the past and the fact consisting in the taking cognisance of thisimage. It is, in other terms, the distinction between the intelligenceand the object. Similarly, all reasoning has an object; there must bematter on which to reason, whether this matter be supplied by thefacts or the ideas. Again, a desire, a volition, an act of reflection, has need of a point of application. One does not will in the air, onewills something; one does not reflect in the void, one reflects over afact or over some difficulty. We may then provisionally distinguish in an inventory of the mind asomething which is perceived, understood, desired, or willed, and, beyond that, the fact of perceiving, of understanding, or desiring, orof willing. To illustrate this distinction by an example, I shall say that ananalogous separation can be effected in an act of vision, by showingthat the act of vision, which is a concrete operation, comprises twodistinct elements: the object seen and the eye which sees. But thisis, of course, only a rough comparison, of which we shall soon see theimperfections when we are further advanced in the study of thequestion. To this activity which exists and manifests itself in the facts offeeling, perceiving, &c. , we can give a name in order to identify andrecognise it: we will call it the consciousness[14] (_la conscience_), and we will call object everything which is not the act ofconsciousness. After this preliminary distinction, to which we shall often refer, wewill go over the principal manifestations of the mind, and we willfirst study the objects of cognition, reserving for another chapterthe study of the acts of cognition--that is to say, of consciousness. We will thus examine successively sensation, idea, emotion, and will. It has been often maintained that the peculiar property of mind is toperceive sensations. It has also been said that thought--that is, theproperty of representing to one's self that which does notexist--distinguishes mind from matter. Lastly, it has not failed to beaffirmed that one thing which the mind brings into the material worldis its power of emotion; and moralists, choosing somewhat arbitrarilyamong certain emotions, have said that the mind is the creator ofgoodness. We will endeavour to analyse these different affirmations. FOOTNOTES: [Footnote 13: See [Note 3], _sup. _ on p. 15. --ED. ] [Footnote 14: The word "_conscience_" is one of those which has beenused in the greatest number of different meanings. Let it be, atleast, understood that _I_ use it here in an intellectual and not amoral sense. I do not attach to the conscience the idea of a moralapprobation or disapprobation, of a duty, of a remorse. The bestexample to illustrate conscience has, perhaps, been formed by LADD. Itis the contrast between a person awake and sleeping a dreamless sleep. The first has consciousness of a number of things; the latter hasconsciousness of nothing. Let me now add that we distinguish fromconsciousness that multitude of things of which one has consciousnessof. Of these we make the object of consciousness. [_Conscience_ hasthroughout been rendered "consciousness. "--ED. ]] CHAPTER II DEFINITION OF SENSATION When making the analysis of matter we impliedly admitted twopropositions: first, that sensation is the _tertium quid_ which isinterposed between the excitant of our sensory nerves and ourselves;secondly, that the aggregate of our sensations is all we can know ofthe outer world, so that it is correct to define this last as thecollection of our present, past, and possible sensations. It is notclaimed that the outer world is nothing else than this, but it isclaimed with good reason that the outer world is nothing else _to us_. It would be possible to draw from the above considerations a cleardefinition of sensation, and especially it would be possible to decidehenceforth from the foregoing whether sensation is a physical or amental phenomenon, and whether it belongs to matter or to mind. Thisis the important point, the one which we now state, and which we willendeavour to resolve. To make the question clearer, we will begin itafresh, as if it were new, and as if the facts hitherto analysed didnot already prejudge the solution. Let us begin by giving a definitionof sensation from the point of view of experimental psychology. Sensation, then, is the phenomenon which is produced and which oneexperiences when an excitant has just acted on one of our organs ofsense. This phenomenon is therefore composed of two parts: an actionexercised from outside by some body or other on our nervous substance;and, then, the fact of feeling this action. This fact of feeling, this state of consciousness, is necessary toconstitute sensation; when it does not exist, it is preferable to givethe phenomenon another name, otherwise the fault is committed ofmixing up separate facts. Physiologists have, on this point, somefaults of terminology with which to reproach themselves: for they haveemployed the word sensibility with too little of the critical spirit. Sensibility, being capacity for sensation, presupposes, like sensationitself, consciousness. It has, therefore, been wrong, in physiology, to speak of the sensibility of the tissues and organs, which, like thevegetable tissues or the animal organs of vegetative life, properlyspeaking, feel nothing, but react by rapid or slow movements to theexcitements they are made to receive. Reaction, by a movement or anykind of modification, to an excitement, does not constitute asensation unless consciousness is joined with it, and, consequently, it would be wiser to give unfelt excitements and reactions the name ofexcitability. The clearest examples of sensation are furnished by the study of man, and are taken from cases where we perceive an external object. Theobject produces upon us an action, and this action is felt; only, insuch cases, the fact of sensation comprises but a very small part ofthe event. It only corresponds, by definition, to the actual action ofthe object. Analysis after analysis has shown that we constantlyperceive far beyond this actual action of objects. Our mind, as wesay, outruns our senses. To our sensations, images come to attachthemselves which result from sensations anteriorly felt in analogouscircumstances. These images produce in us an illusion, and we takethem for sensations, so that we think we perceive something which isbut a remembrance or an idea; the reason being that our mind cannotremain in action in the presence of a sensation, but unceasinglylabours to throw light upon it, to sound it, and to arrive at itsmeaning, and consequently alters it by adding to it. This addition isso constant, so unavoidable, that the existence of an isolatedsensation which should be perceived without the attachment of images, without modification or interpretation, is well-nigh unrealisable inthe consciousness of an adult. It is a myth. Let us, however, imagine this isolation to be possible, and that wehave before us a sensation free from any other element. What is thissensation? Does it belong to the domain of physical or of moralthings? Is it a state of matter or of mind? I can neither doubt nor dispute that sensation is, in part, apsychological phenomenon, since I have admitted, by the verydefinition I have given of it, that sensation implies consciousness. We must, therefore, acknowledge those who define it as _a state ofconsciousness_ to be right, but it would be more correct to call itthe _consciousness of a state_, and it is with regard to the nature ofthis state that the question presents itself. It is only this statewhich we will now take into consideration. It is understood thatsensation contains both an impression and a cognition. Let us leavetill later the study of the act of cognition, and deal with theimpression. Is this impression now of a physical or a mental nature?Both the two opposing opinions have been upheld. In this there isnothing astonishing, for in metaphysics one finds the expression ofevery possible opinion. But a large, an immense majority ofphilosophers has declared in favour of the psychological nature of theimpression. Without even making the above distinction between theimpression and the act of cognition, it has been admitted that theentire sensation, taken _en bloc_, is a psychological phenomenon, amodification of our consciousness and a peculiar state of our minds. Descartes has even employed this very explicit formula: "The objectswe perceive are within our understanding. " It is curious to see howlittle trouble authors take to demonstrate this opinion; they declareit to be self-evident, which is a convenient way of avoiding allproof. John Stuart Mill has no hesitation in affirming that: "Themind, in perceiving external objects, can only take notice of its ownconditions. " And Renouvier expresses the same arbitrary assertion withgreater obscurity when he writes: "The monad is constituted by thisrelation: the connection of the subject with the object within thesubject. "[15] In other words, it is laid down as an uncontrovertibleprinciple that "the mental can only enter into direct relations withthe mental. " That is what may be called "the principle of Idealism. " This principle seems to me very disputable, and it is to me anastonishing thing that the most resolute of sceptics--Hume, forexample--should have accepted it without hesitation. I shall firstenunciate my personal opinion, then make known another which onlydiffers from mine by a difference of words, and finally I will discussa third opinion, which seems to me radically wrong. My personal opinion is that sensation is of a mixed nature. It ispsychical in so far as it implies an act of consciousness, andphysical otherwise. The impression on which the act of cognitionoperates, that impression which is directly produced by the excitantof the nervous system, seems to me, without any doubt, to be of anentirely physical nature. This opinion, which I make mine own, hasonly been upheld by very few philosophers--Thomas Reid perhaps, andWilliam Hamilton for certain; but neither has perceived its deep-lyingconsequences. What are the arguments on which I rely? They are of different orders, and are arguments of fact and arguments of logic. I shall first appealto the natural conviction of those who have never ventured intometaphysics. So long as no endeavour has been made to demonstrate thecontrary to them, they believe, with a natural and naïve belief, thatmatter is that which is seen, touched and felt, and that, consequently, matter and our senses are confounded. They would begreatly astonished to be informed that when we appear to perceive theouter world, we simply perceive our ideas; that when we take the trainfor Lyons we enter into one state of consciousness in order to attainanother state of consciousness. Now, the adherents of this natural and naïve opinion have, as they sayin the law, the right of possession (_possession d'état_); they arenot plaintiffs but defendants; it is not for them to prove they are inthe right, it has to be proved against them that they are in thewrong. Until this proof is forthcoming they have a presumption intheir favour. Are we here making use of the argument of common opinion of mankind, of which ancient philosophy made so evident an abuse? Yes, and no. Yes, for we here adopt the general opinion. No, for we only adopt ittill the contrary be proved. But who can exhibit this proof to thecontrary? On a close examination of the question, it will be perceivedthat sensation, taken as an object of cognition, becomes confused withthe properties of physical nature, and is identified with them, bothby its mode of apparition and by its content. By its mode ofapparition, sensation holds itself out as independent of us, for it isat every instant an unexpected revelation, a source of freshcognitions, and it offers a development which takes place without andin spite of our will; while its laws of co-existence and of successiondeclare to us the order and march of the material universe. Besides, by its content, sensation is confounded with matter. When aphilosopher seeks to represent to himself the properties of a materialobject, --of a brain, for example--in order to contrast them with theproperties of a psychical activity, it is the properties of sensationthat he describes as material; and, in fact, it is by sensation, andsensation alone, that we know these properties. Sensation is so littledistinct from them that it is an error to consider it as a means, aprocess, an instrument for the knowledge of matter. All that we knowof matter is not known in or by sensation, but constitutes sensationitself; it is not by the aid of sensation that we know colour; colouris a sensation, and the same may be said of form, resistance, and thewhole series of the properties of matter. They are only our sensationsclothed with external bodies. It is therefore absolutely legitimate toconsider a part of our sensations, the object part, as being ofphysical nature. This is the opinion to which I adhere. We come to the second opinion we have formulated. It is, in appearanceat least, very different from the first. Its supporters agree that theentire sensation, taken _en bloc_ and unanalysed, is to be termed apsychological phenomenon. In this case, the act of consciousness, included in the sensation, continues to represent a psychical element. They suppose, besides, that the object on which this act operates ispsychical; and finally, they suppose that this object or thisimpression was provoked in us by a physical reality which is kept inconcealment, which we do not perceive, and which remains unknowable. This opinion is nowise absurd in itself: but let us examine itsconsequences. If we admit this thesis, that sensations aremanifestations of mind which, although provoked by material causes, are of a purely mental nature, we are forced to the conclusion that weknow none of the properties of material bodies, since we do not enterinto relations with these bodies. The object we apprehend byperception is, according to this hypothesis, solely mental. To drawtherefrom any notion on material objects, it would have to be supposedthat, by some mysterious action, the mental which we know resemblesthe physical which we do not know, that it retains the reflection ofit, or even that it allows its colour and form to pass, like atransparent pellicle applied on the contour of bodies. Here arehypotheses very odd in their realism. Unless we accept them, how is itcomprehensible that we can know anything whatever of physical nature?We should be forced to acknowledge, following the example of severalphilosophers, that the perception of the physical is an illusion. As a compensation, that which this system takes from matter itattributes to mind, which turns our familiar conceptions upside down. The qualities of sensation detached from matter will, when applied tomind, change its physiognomy. There are sensations of extent, weight, space, and form. If these sensations are turned into psychical events, we shall have to grant to these events, to these manifestations of themind, the properties of extent, of weight, of form. We shall have tosay that mind is a resisting thing, and that it has colour. It may be said that this fantasy of language is not very serious. Sobe it. But then what remains of the dualism of mind and matter? It isat least singularly compromised. We may continue to suppose thatmatter exists, and even that it is matter which provokes in our mindthose events which we call our sensations; but we cannot know if byits nature, its essence, this matter differs from that of mind, sincewe shall be ignorant of all its properties. Our ignorance on thispoint will be so complete that we shall not even be able to knowwhether any state which we call mental may not be physical. Thedistinction between physical and mental will have lost its _raisond'être_, since the existence of the physical is necessary to give ameaning to the existence of the mental. We are brought, whether welike it or not, to an experimental monism, which is neither psychicalnor physical; panpsychism and panmaterialism will have the samemeaning. [16] But this monism can be only transitory, for it is more in the wordsthan in the thing itself. It is brought about by the terminologyadopted, by the resolution to call mental all the phenomena that it ispossible to know. Luckily, our speculations are not at the mercy ofsuch trifling details as the details of language. Whatever names maybe given to this or that, it will remain none the less true thatnature will continue to present to us a contrast between phenomenawhich are flints, pieces of iron, clods of earth, brains--and someother phenomena which we call states of consciousness. Whatever be thevalue of this dualism, it will have to be discussed even in thehypothesis of panpsychism. [17] As for myself, I shall also continue tomake a distinction between what I have called objects of cognition andacts of cognition, because this is the most general distinction thatcan be traced in the immense field of our cognitions. There is noother which succeeds, to the same degree, in dividing this field intotwo, moreover, this distinction is derived directly from observation, and does not depend for its validity on the physical or mental natureof the objects. Here is, then, a duality, and this duality, even whenit does not bear the names physical and moral, should necessarily playthe same part, since it corresponds to the same distinction of fact. In the end, nothing will be changed, and this second opinion mustgradually merge into the one first stated by me, and of which I takethe responsibility. We may, therefore, put it out of consideration. I have mentioned a third opinion, stating that it appeared to me to beradically false. Outwardly it is the same as the last; looked atsuperficially it seems even confused with it; but, in reality it is ofa totally different nature. It supposes that sensation is an entirelypsychological phenomenon. Then, having laid down this thesis, itundertakes to demonstrate it by asserting that sensation differs fromthe physical fact, which amounts to supposing that we cannot knowanything but sensations, and that physical facts are known to usdirectly and by another channel. This is where the contradiction comesin. It is so apparent that one wonders how it has been overlooked byso many excellent minds. In order to remove it, it will be sufficientto recollect that we do not know anything other than sensations; it istherefore impossible to make any distinction between the physicalobject and the object of cognition contained in every sensation. Theline of demarcation between the physical and the moral cannot passthis way, since it would separate facts which are identical. We can, therefore, only deplore the error of all those who, to expressthe difference between mind and matter, have sought a contrast betweensensation and physical facts. Physiologists, with hardly an exception, have fallen into this error; when contemplating in imagination thematerial working of the brain, they have thought that between themovement of cerebral matter and sensation there was a gulf fixed. Thecomparison, to have been correct, required to be presented in quiteanother way. A parallel, for instance, should have been drawn betweena certain cerebral movement and the act of consciousness, and thereshould have been said: "The cerebral motion is the physicalphenomenon, the act of consciousness the psychical. " But thisdistinction has not been made. It is sensation _en bloc_ which iscompared to the cerebral movement, as witness a few passages I willquote as a matter of curiosity, which are borrowed from philosophersand, especially, from physiologists. While philosophers take as a principle of idealism, that the mentalcan only know the mental, physiologists take, as a like principle, the heterogeneity existing, or supposed to exist, between the nerveimpression and the sensation. "However much we may follow theexcitement through the whole length of the nerve, " writes Lotze, [18]"or cause it to change its form a thousand times and to metamorphoseitself into more and more delicate and subtle movements, we shallnever succeed in showing that a movement thus produced can, by itsvery nature, cease to exist as movement and be reborn in the shape ofsensation. .. . " It will be seen that it is on the opposition betweenmolecular movement and sensation, that Lotze insists. In like mannerFerrier: "But how is it that the molecular modifications in thecerebral cells coincide with the modifications of the consciousness;how, for instance, do luminous vibrations falling upon the retinaexcite the modification of consciousness called _visual sensation_?These are problems we cannot solve. We may succeed in determining theexact nature of the molecular changes which take place in the cerebralcells when a sensation is felt, but this will not bring us an inchnearer to the explanation of the fundamental nature of sensation. "Finally, Du Bois Reymond, in his famous discussion in 1880, on theseven enigmas of the world, speaks somewhat as follows: "Theastronomical knowledge of the encephalon, that is, the most intimateto which we can aspire, only reveals to us matter in motion. But noarrangement nor motion of material particles can act as a bridge bywhich we can cross over into the domain of intelligence. .. . Whatimaginable link is there between certain movements of certainmolecules in my brain, on the one hand, and on the other handprimitive, undefinable, undeniable facts such as: I have the sensationof softness, I smell the odour of a rose, I hear the sound of anorgan, I see a red colour, &c. .. . " These three quotations show very conclusively that their authorsthought they could establish the heterogeneity of the two phenomena byopposing matter to sensation. It must be recognised that they havefallen into a singular error; for matter, whatever it may be, is forus nothing but sensation; matter in motion, I have often repeated, isonly a quite special kind of sensation; the organic matter of thebrain, with its whirling movements of atoms, is only sensation. Consequently, to oppose the molecular changes in the brain to thesensation of red, blue, green, or to an undefined sensation of anysort, is not crossing a gulf, and bringing together things whichcannot be compared, it is simply comparing one sensation to anothersensation. There is evidently something equivocal in all this; and I pointed thisout when outlining and discussing the different theories of matter. Itconsists in taking from among the whole body of sensations certain ofthem which are considered to be special, and which are then investedwith the privilege of being more important than the rest and thecauses of all the others. This is about as illegitimate as to chooseamong men a few individuals to whom is attributed the privilege ofcommanding others by divine right. These privileged sensations whichbelong to the sight, the touch, and the muscular sense, and which areof large extent, are indeed extensive. They have been undulyconsidered as objective and as representing matter because they arebetter known and measurable, while the other sensations, theunextensive sensations of the other senses, are considered assubjective for the reasons that they are less known and lessmeasurable: and they are therefore looked on as connected with oursensibility, our Ego, and are used to form the moral world. We cannot subscribe to this way of establishing the contrast betweenmatter and thought, since it is simply a contrast between twocategories of sensations, and I have already asserted that thepartitioning-out of sensations into two groups having differentobjective values, is arbitrary. FOOTNOTES: [Footnote 15: CH. RENOUVIER et L. PRAT, _La Nouvelle Monadologie_, p. 148. ] [Footnote 16: An American author, MORTON PRINCE, lately remarked this:_Philosophical Review_, July 1904, p. 450. ] [Footnote 17: This FLOURNOY recently has shown very wittily. See in_Arch. De Psychol. _, Nov. 1904, his article on Panpsychism. ] [Footnote 18: This extract, together with the two subsequent, areborrowed from an excellent lecture by FLOURNOY, on _Métaphysique etPhysiologie_. Georg: Geneva, 1890. ] CHAPTER III DEFINITION OF THE IMAGE Going on with our inventory, after sensations come images, ideas, andconcepts; in fact, quite a collection of phenomena, which, aregenerally considered as essentially psychological. So long as one does not carefully analyse the value of ideas, oneremains under the impression that ideas form a world apart, which issharply distinguished from the physical world, and behaves towards itas an antithesis. For is not conception the contrary of perception?and is not the ideal in opposition to reality? Thoughts have some characteristics of fancy, of freedom, even ofunreality, which are wanting to the prosaicness of heavy materialthings. Thoughts sport with the relations of time and space; they flyin a moment across the gulf between the most distant objects; theytravel back up the course of time; they bring near to us eventscenturies away; they conceive objects which are unreal; they imaginecombinations which upset all physical laws, and, further, theseconceptions remain invisible to others as well as to ourselves. Theyare outside the grip of reality, and constitute a world which becomes, for any one with the smallest imagination, as great and as importantas the world called real. One may call in evidence the poets, novelists, artists, and the dreamers of all kinds. When life becomestoo hard for us, we fly to the ideal world, there to seekforgetfulness or compensation. It is, therefore, easy to understand, that it should have beenproposed to carry into ideation the dichotomy between the physical andthe moral. Many excellent authors have made the domain of the mindbegin in the ideal. Matter is that which does not think. Descartes, inhis _Discours de la Méthode_ (4th part), remarking that he may pretend"not to have a body, and that there is no world or place in which heexists, but that he cannot pretend that he does not think, " concludesby saying that the mind is "a substance, all whose essence or natureis merely to think, and which has no need of either place or any othermaterial thing, in order to exist;" in short, that "the soul isabsolutely distinct from the body. "[19] Let us, then, examine in what measure this separation betweenperception and ideation can be legitimately established. If we acceptthis separation, we must abandon the distinction I proposed betweenacts and objects of cognition, or, at least, admit that thisdistinction does not correspond to that between the physical and themoral, since thoughts, images, recollections, and even the mostabstract conceptions, all constitute, in a certain sense, objects ofcognition. They are phenomena which, when analysed, are clearlycomposed of two parts, an object and a cognition. Their logicalcomposition is, indeed, that of an external perception, and there isin ideation exactly the same duality as in sensation. Consequently, ifwe maintain the above distinction as a principle of classification forall knowable phenomena, we shall be obliged to assign the sameposition to ideas as to sensations. The principal difference we notice between sensation and idea is, itwould seem, the character of unreality in the last named; but thisopposition has not the significance we imagine. Our mental visiononly assumes this wholly special character of unreality underconditions in which it is unable to harmonise with the real vision. Taine has well described the phases of the reduction of the image bysensation: it is at the moment when it receives the shock of an imagewhich contradicts it, that the image appears as illusory. [20] Let ussuppose that we are sitting down dreaming and watching the passing byof our images. If, at this moment, a sudden noise calls us back toreality, the whole of our mental phantasmagoria disappears as if bythe wave of a magic wand, and it is by thus vanishing that the imageshows its falsity. It is false because it does not accord with thepresent reality. But, when we do not notice a disagreement between these two modes ofcognition, both alike give us the impression of reality. If I evoke areminiscence and dwell attentively on the details, I have theimpression that I am in face of the reality itself. "I feel as if Iwere there still, " is a common saying; and, among the recollections Ievoke, there are some which give me the same certitude as theperception of the moment. Certain witnesses would write theirdepositions with their blood. One does not see this every day; butstill one does see it. Further, there are thousands of circumstances where the ideation isneither in conflict with the perception nor isolated from it, but inlogical continuity with it. This continuity must even be considered asthe normal condition. We think in the direction of that which weperceive. The image seems to prepare the adaptation of the individualto his surroundings; it creates the foresight, the preparation of themeans, and, in a word, everything which constitutes for us a finalcause. Now, it is very necessary that the image appear real to beusefully the substitute of the sensation past or to come. Let us establish one thing more. Acting as a substitute, the image notonly appears as real as the sensation, it appears to be of the samenature; and the proof is that they are confounded one with the other, and that those who are not warned of the fact take one for the other. Every time a body is perceived, as I previously explained, there areimages which affix themselves to the sensation unnoticed. We think weperceive when we are really remembering or imagining. This addition ofthe image to the sensation is not a petty and insignificant accessory;it forms the major part, perhaps nine-tenths, of perception. Hencearise the illusions of the senses, which are the result, not ofsensations but of ideas. From this also comes the difficulty ofknowing exactly what, under certain circumstances, is observation orperception, where the fact perceived ends, and where conjecturebegins. Once acquainted with all these possibilities of errors, howcan we suppose a radical separation between the sensation and theimage? Examined more closely, images appear to us to be divisible into asmany kinds as sensations: visual images correspond to visualsensations, tactile to tactile, and so on with all the senses. That which we experience in the form of sensation, we can experienceover again in the form of image, and the repetition, generally weakerin intensity and poorer in details, may, under certain favourablecircumstances, acquire an exceptional intensity, and even equalreality: as is shown by hallucinations. Here, certainly, are verysound reasons for acknowledging that the images which are at thebottom of our thoughts, and form the object of them, are therepetition, the modification, the transposition, the analysis or thesynthesis of sensations experienced in the past, and possessing, inconsequence, all the characteristics of bodily states. I believe thatthere is neither more nor less spirituality in the idea than in thesensation. That which forms its spirituality is the implied act ofcognition; but its object is material. I foresee a final objection: I shall be told that even when theunreality of the image is not the rule, and appears only under certaincircumstances, it nevertheless exists. This is an important fact. Ithas been argued from the unreality of dreams and hallucinations inwhich we give a body to our ideas, that we do not in reality perceiveexternal bodies, but simply psychical states and modifications of oursouls. If our ideas consist--according to the hypothesis I uphold--inphysical impressions which are felt, we shall be told that theseparticular impressions must participate in the nature of everythingphysical; that they are real, and always real; that they cannot beunreal, fictitious, and mendacious, and that, consequently, thefictitious character of ideation becomes inexplicable. Two words of answer are necessary to this curious argument, which isnothing less than an effort to define the mental by the unreal, and tosuppose that an appearance cannot be physical. No doubt, we say, everyimage, fantastical as it may seem as signification, is real in acertain sense, since it is the perception of a physical impression;but this physical nature of images does not prevent our making adistinction between true and false images. To take an analogousexample: we are given a sheet of proofs to correct, we delete certainredundant letters, and, although they are printed with the same typeas the other letters, we have the right to say they are false. Again, in a musical air, we may hear a false note, though it is as real asthe others, since it has been played. This distinction between realityand truth ought to be likewise applied to mental images. All are real, but some are false. They are false when they do not accord with thewhole reality; they are true when they agree; and every image ispartly false because, being an image, it does not wholly accord withthe actual perceptions. It creates a belief in a perception which doesnot occur; and by developing these ideas we could easily demonstratehow many degrees of falsehood there are. Physiologically, we may very easily reconcile the falsity of the imagewith the physical character of the impression on which it is based. The image results from a partial cerebral excitement, which sensationresults from an excitement which also acts upon the peripheral sensorynerves, and corresponds to an external object--an excitant which theimage does not possess. This difference explains how it is that theimage, while resulting from a physical impression, may yet be in agreat number of cases declared false--that is to say, may berecognised as in contradiction to the perceptions. To other minds, perhaps, metaphysical reasoning will be moresatisfactory. For those, we propose to make a distinction between twonotions, Existence or Reality, on the one hand, and Truth, on theother. Existence or Reality is that of which we have an immediateapprehension. This apprehension occurs in several ways. In perception, in the first place. I perceive the reality of my body, of a table, thesky, the earth, in proportion to my perception of them. They exist, for if they did not, I could not perceive them. Another way ofunderstanding reality is conception or thought. However much I mayrepresent a thing to myself as imaginary, it nevertheless exists in acertain manner, since I can represent it to myself. I therefore, inthis case, say that it is real or it exists. It is of courseunderstood, that in these definitions I am going against the ordinaryacceptation of the terms; I am taking the liberty of proposing newmeanings. This reality is, then, perceived in one case and conceivedin the other. Perceptibility or conceivability are, then, the twoforms which reality may assume. But _reality_ is not synonymous with_truth_; notwithstanding the custom to the contrary, we may wellintroduce a difference between these two terms. Reality is that whichis perceived or conceived; truth is that which accords with the wholeof our knowledge. Reality is a function of the senses or of ideation;truth is a function of reasoning or of the reason. For cognition to be complete, it requires the aid of all thesefunctions. And, in fact, what does conception by itself give? Itallows us to see if a thing is capable of representation. This is nota common-place thing, I will observe in passing; for many things wename are not capable of representation, and there is often a criticismto be made; we think we are representing, and we are not. What iscapable of representation exists as a representation, but is it true?Some philosophers have imagined so, but they are mistaken; what wesucceed in conceiving is alone possible. Let us now take the Perceptible. Is what one perceives true? Yes, inmost cases it is so in fact; but an isolated perception may be false, and disturbed by illusions of all kinds. It is all very well to say, "I see, I touch. " There is no certainty through the senses alone inmany circumstances that the truth has been grasped. If I am shown thespirit of a person I know to be dead, I shall not, notwithstanding thetestimony of my eyes, believe it to be true, for this apparition wouldupset all my system of cognitions. Truth is that which, being deemed conceivable, and being reallyperceived, has also the quality of finding its place, its relation, and its confirmation in the whole mass of cognitions previouslyacquired. These distinctions, [21] if developed, would readily demonstrate thatthe advantages of observation are not eclipsed by those ofspeculation; and that those of speculation, in their turn, do notinterfere with those of observation. But we have not time to developthese rules of logic; it will be sufficient to point out theirrelation to the question of the reality of mental images. Here are myconclusions in two words. Physical phenomena and images are alwaysreal, since they are perceived or conceived; what is sometimes wantingto them, and makes them false, is that they do not accord with therest of our cognitions. [22] Thus, then, are all objections overruled, in my opinion at least. Wecan now consider the world of ideas as a physical world; but it isone of a peculiar nature, which is not, like the other, accessible toall, and is subject to its own laws, which are laws of association. Bythese very different characteristics, it separates itself so sharplyfrom the outer world that all endeavour to bring the two togetherseems shocking; and it is very easy to understand that many mindsshould wish to remain faithful to the conception that ideas form amental or moral world. No metaphysical reasoning could prevail againstthis sentiment, and we must give up the idea of destroying it. But wethink we have shown that idea, like sensation, comprises at the sametime the physical and the mental. FOOTNOTES: [Footnote 19: Let me say, in passing, that this separation thatDESCARTES thinks he can establish between perception and ideation, isonly conceivable on condition that it be not too closely examined, andthat no exact definition of ideation be given. If we remark, in fact, that all thought is a reproduction, in some degree, of a sensation, wearrive at this conclusion: that a thought operated by a soul distinctfrom the body would be a thought completely void and without object, it would be the thought of nothingness. It is not, therefore, conceivable. Consequently the criterion, already so dangerous, whichDESCARTES constantly employs--to wit: that what we clearly conceive istrue--cannot apply to thought, if we take the trouble to analyse itand to replace a purely verbal conception by intuition. ] [Footnote 20: I somewhat regret that TAINE fell into the common-placeidea of the opposition of the brain and thought; he took up again thisold idea without endeavouring to analyse it, and only made it his ownby the ornamentation of his style. And as his was a mind of powerfulsystematisation, the error which he committed led him into much widerconsequences than the error of a more common mind would have done. ] [Footnote 21: I have just come across them again in an ingenious noteof C. L. HERRICK: _The Logical and Psychological Distinction betweenthe True and the Real_ (_Psych. Rev. _, May 1904). I entirely agreewith this author. But it is not he who exercised a suggestion over mymind; it was M. BERGSON. See _Matière et Mémoire_, p. 159. ] [Footnote 22: In order to remain brief, I have not thought fit toallude in the text to a question of metaphysics which closely dependson the one broached by me: the existence of an outer world. Philosophers who define sensation as a modality of our Ego are muchembarrassed later in demonstrating the existence of an outer world. Having first admitted that our perception of it is illusory, since, when we think we perceive this world, we have simply the feeling ofthe modalities of our Ego, they find themselves powerless todemonstrate that this illusion corresponds to a truth, and invoke indespair, for the purpose of their demonstration, instinct, hallucination, or some _a priori_ law of the mind. The position wehave taken in the discussion is far more simple. Since every sensationis a fragment of matter perceived by a mind, the aggregate ofsensations constitutes the aggregate of matter. There is in this nodeceptive appearance, and consequently no need to prove a realitydistinct from appearances. As to the argument drawn from dreams andhallucinations which might be brought against this, I have shown howit is set aside by a distinction between perceptibility and truth. Itis no longer a matter of perception, but of reasoning. In other words, all that we see, even in dreams, is real, but is not in its dueplace. ] CHAPTER IV DEFINITION OF THE EMOTIONS After sensations and images, we have to name among the phenomena ofconsciousness, the whole series of affective states--our pleasures andour pains, our joys and our griefs, our sentiments, our emotions, andour passions. It is universally admitted that these states are of amental nature, for several reasons. (1) We never objectivate them aswe do our sensations, but we constantly consider them as indwelling orsubjective states. This rule, however, allows an exception for thepleasure and the pain termed physical, which are often localised inparticular parts of our bodies, although the position attributed tothem is less precise than with indifferent sensations. (2) We do notalienate them as we do our indifferent sensations. The sensations ofweight, of colour, and of form serve us for the construction of bodieswhich appear to us as perceived by us, but as being other thanourselves. On the contrary, we constantly and without hesitation referour emotional states to our _Ego_. It is I who suffer, we say, I whocomplain, I who hope. It is true that this attribution is notabsolutely characteristic of mental phenomena, for it happens that weput a part of our Ego into material objects, such as our bodies, andeven into objects separate from our bodies, and whose sole relation tous is that of a legal proprietorship. We must guard against thesomewhat frequent error of identifying the Ego with the psychical. These two reasons sufficiently explain the tendency to see onlypsychological states in the emotional ones; and, in fact, thoseauthors who have sought to oppose mind to matter have not failed tointroduce emotion into their parallel as representing the essence ofmind. On this point I will recall the fine ironical image used byTyndall, the illustrious English physicist, to show the abyss whichseparates thought from the molecular states of the brain. "Let ussuppose, " he says, "that the sentiment love, for example, correspondsto a right-hand spiral movement of the molecules of the brain and thesentiment hatred to a left-hand spiral movement. We should then knowthat when we love, a movement is produced in one direction, and whenwe hate, in another. But the Why would remain without an answer. " The question of knowing what place in our metaphysical theory we oughtto secure for emotion seems difficult to resolve, and we even findsome pleasure in leaving it in suspense, in order that it may beunderstood that a metaphysician is not compelled to explaineverything. Besides, the difficulties which atop us here arepeculiarly of a psychological order. They proceed from the fact thatstudies on the nature of the emotions are still very little advanced. The physical conditions of these states are pretty well known, andtheir psychical and social effects have been abundantly described; butvery little is known as to what distinguishes an emotion from athought. Two principal opinions may be upheld in the actual state of ouracquaintance with the psychology of the feelings. When we endeavour topenetrate their essential and final nature, we have a choice betweentwo contrary theories. The first and traditional one consists in seeing in emotion aphenomenon _sui generis_; this is very simple, and leaves nothing moreto be said. The second bears the name of the intellectualist theory. It consistsin expunging the characteristic of the affective states. We considerthem as derivative forms of particular modes of cognition, and theyare only "confused intelligence. " This intellectualist thesis is ofearly date; it will be found in Herbart, who, by-the-by, gave it apeculiar form, by causing the play of images to intervene in theformation of the feelings. However, this particular point is of slightImportance. The intellectualist theory is more vast than Herbartism;it exists in all doctrines in which the characteristic differencebetween thought and feeling is expunged and feeling is brought back tothought. One of the clearest means of so doing consists in only seeingin the feeling the fact of perceiving something. To perceive is, infact, the property of intelligence; to reason, to imagine, to judge, to understand, is always, in a certain sense, to perceive. It has beenimagined that emotion is nothing else than a perception of a certainkind, an intellectual act strictly comparable to the contemplation ofa landscape. Only, in the place of a landscape with placid featuresyou must put a storm, a cataclysm of nature; and, instead of supposingthis storm outside us, let it burst within us, let it reach us, not bythe outer senses of sight and condition, but by the inner senses. Whatwe then perceive will be an emotion. Such is the theory that two authors--W. James and Lange--happened todiscover almost at the same time, Lange treating it as a physiologistand W. James as a philosopher. Their theory, at first sight, appearssingular, like everything which runs counter to our mental habits. Itlays down that the symptoms which we all till now have considered asthe physiological consequence, the translation, and the distanteffects of the emotions, constitute their essential base. Theseeffects are: the expression of the physiognomy, the gesture, the cry, and the speech; or the reflex action on the circulation, the pallor orblushing, the heat mounting to the head, or the cold of the shiverwhich passes over the body. Or it is the heart, which hastens orslackens its beats, or makes them irregular, or enfeebles, or augmentsthem. Or the respiration, which changes its rhythm, or increases, oris suspended. Or else it is the secretion of the saliva or of thesweat, which flows in abundance or dries up. Or the muscular force, which is increased or decays. Or the almost undefinable organictroubles revealed to us by the singing in the ears, constriction ofthe epigastrium, the jerks, the trembling, vertigo, or nausea--allthis collection of organic troubles which comes more or lessconfusedly to our consciousness under the form of tactile, muscular, thermal, and other sensations. Until now this category of phenomenahas been somewhat neglected, because we saw in it effects andconsequences of which the rôle in emotion itself seemed slight, since, if they could have been suppressed, it was supposed that emotion wouldstill remain. The new theory commences by changing the order ofevents. It places the physical symptoms of the emotions at the verybeginning, and considers them the direct effects of the externalexcitant, which is expressed by this elegant formula: "It used to besaid, 'I perceive a danger; I am frightened, I tremble. ' Now we mustsay, 'I tremble before a danger, first, and it is after havingtrembled that I am frightened. '" This is not a change in order only;it is something much more serious. The change is directed to thenature of emotion. It is considered to exist in the organicderangements indicated above. These derangements are the basis ofemotion, its physical basis, and to be moved is to perceive them. Takeaway from the consciousness this physical reflex, and emotion ceases. It is no longer anything but an idea. This theory has at least the merit of originality. It also pleases oneby its great clearness--an entirely intellectual clearness, we maysay; for it renders emotion comprehensible by enunciating it in termsof cognition. It eliminates all difference which may exist between aperception and an emotion. Emotion is no longer anything but a certainkind of perception, the perception of the organic sensations. This reduction, if admitted, would much facilitate the introduction ofemotion into our system, which, being founded on the distinctionbetween the consciousness and the object, is likewise anintellectualist system. The definition of emotion, as it is taught byW. James, seems expressly made for us who are seeking to resolve allintellectual states into physical impressions accompanied byconsciousness. By the side of emotion we may place, as demanding the same analyticalstudy, the feeling of effort. We ought to inquire with effort, as hasbeen done with emotion, what is the psychological nature of thisphenomenon; and in the same way that there exists an intellectualisttheory of the emotions, viz. That of James, who reduces all thehistory of the emotions to intelligence, so there exists anintellectualist theory of effort, which likewise tends to bring back, all will to intelligence. It is again the same author, that truegenius, W. James, who has attempted this reduction. I do not knowwhether he has taken into account the parallelism of the two theories, but it is nevertheless evident. Effort, that basis of activity, thatstate of consciousness which so many psychologists have described assomething _sui generis_, becomes to James a phenomenon of perception. It is the perception of sensations proceeding from the muscles, thetendons, the articulations, the skin, and from all the organs directlyor indirectly concerned in the execution of movement. To be consciousof an effort would then be nothing else than to receive all thesecentripetal sensations; and what proves this is, that theconsciousness of effort when most clearly manifested is accompanied bysome muscular energy, some strong contraction, or some respiratorytrouble, and yields if we render the respiration again regular and putthe muscles back into repose. To my great regret I can state nothing very clear regarding theseproblems. The attempt to intellectualise all psychical problems isinfinitely interesting, and leads to a fairly clear conception, bywhich everything is explained by a mechanism reflected in a mirror, which is the consciousness. But we remain perplexed, and we askourselves whether this clearness of perception is not somewhatartificial, whether affectivity, emotivity, tendency, will, are reallyall reduced to perceptions, or whether they are not rather irreducibleelements which should be added to the consciousness. Does not, forinstance, desire represent a complement of the consciousness? Do notdesire and consciousness together represent a something which does notbelong to the physical domain and which forms the moral world? Thisquestion I leave unanswered. CHAPTER V DEFINITION OF THE CONSCIOUSNESS--THE RELATION SUBJECT-OBJECT After having separated from the consciousness that which it is not, let us try to define what it is. This and the two following chaptersare devoted to this study. A theory has often been maintained with regard to the consciousness;namely, that it supposes a relation between two terms--a subject andan object, and that it consists exactly in the feeling of thisrelation. By subject is understood the something that hasconsciousness; the object is the something of which we are conscious. Every thought, we are told, implies subject and object, therepresenter and the represented, the _sentiens_ and the _sensum_--theone active, the other passive, the active acting on the passive, the_ego_ opposed to the _non ego_. This opinion is almost legitimised by current language. When speakingof our states of consciousness, we generally say, "I am conscious; itis I who have consciousness, " and we attribute to our I, to our Ego, to our personality, the rôle of subject. But this is not a peremptoryargument in favour of the above opinion; it is only a presumption, and, closely examined, this presumption seems very weak. Hitherto, when analysing the part of mind, we have employednon-committal terms: we have said that sensation impliedconsciousness, and not that sensation implied something which isconscious. [23] The difference may appear too subtle, but it is not; itconsists in taking from consciousness the notion of a subject beingconscious and replacing it by the very act of consciousness. My description applies very exactly, I think, to the facts. When weare engaged in a sensation, or when we perceive something, aphenomenon occurs which simply consists in having consciousness of athing. If to this we add the idea of the subject, which hasconsciousness, we distort the event. At the very moment when it istaking place, it is not so complicated; we complicate it by adding toit the work of reflection. It is reflection which constructs thenotion of the subject, and it is this which afterwards introduces thisconstruction into the states of consciousness; in this way the stateof consciousness, by receiving this notion of subject, acquires acharacter of duality it did not previously possess. There are, inshort, two separate acts of consciousness, and one is made the subjectof the other. "Primitively, " says Rabier, "there is neitherrepresentative nor represented; there are sensations, representations, facts of consciousness, and that is all. Nothing is more exact, in myopinion, than this view of Condillac's:--that primitively, theinanimate statue is entirely the sensation that it feels. To itself itis all odour and all savour; it is nothing more, and this sensationincludes no duality for the consciousness. It is of an absolutesimplicity. " Two arguments may be advanced in favour of this opinion. The first isone of logic. We have divided all knowledge into two groups--objectsof cognition, and acts of cognition. What is the subject of cognition?Does it form a new group? By no means; it forms part of the firstgroup, of the object group; for it is something to be known. Our second argument is one of fact. It consists in remembering thatwhich in practice we understand by the subject of cognition; orrather, metaphorically we represent this subject to ourselves as anorgan--the eye that sees or the hand that touches--and we represent toourselves the relation subject-object in the shape of a materialrelation between two distinct bodies which are separated by aninterval and between which some action is produced which unites them. Or else, confusing the subject and the Ego, which are nevertheless twodifferent notions, we place the Ego in the consciousness of themuscular effort struggling against something which resists. Or, finally and still more frequently, we represent the subject toourselves by confusing it with our own personality; it is a part ofour biography, our name, our profession, our social status, our body, our past life foreshortened, our character, or, in a word, our civilpersonality, which becomes the subject of the relation subject-object. We artificially endow this personality with the faculty of havingconsciousness; and it results from this that the entity consciousness, so difficult to define and to imagine, profits by all this factitiousaddition and becomes a person, visible and even very large, in fleshand bone, distinct from the object of cognition, and capable of livinga separate life. It is not difficult to explain that all this clearness in therepresentation of ideas is acquired by a falsification of the facts. So sensorial a representation of consciousness is very unfaithful;for our biography does not represent what we have called acts ofconsciousness, but a large slice of our past experience--that is tosay, a synthesis of bygone sensations and images, a synthesis ofobjects of consciousness; therefore a complete confusion between theacts of consciousness and their objects. The formation of thepersonality seems to me to have, above all, a legal and socialimportance. [24] It is a peculiar grouping of states of consciousnessimposed by our relations with other individuals. But, metaphysically, the subject thus understood is not distinguished from the object, andthere is nothing to add to our distinction between the object and theact of consciousness. Those who defend the existence of the subject point out that thissubject properly constitutes the Ego, and that the distinction of thesubject and the object corresponds to the distinction of the Ego andnon-Ego, and furnishes the separation between the physical and themoral so long sought. It is evidently very enticing to make of the Ego thus a primitivenotion of the consciousness; but this view of the Ego as opposed tothe non-Ego in no way corresponds to that of the mental and thephysical. The notion of the Ego is much larger, much more extensible, than that of the mental; it is as encroaching as human pride, itgrasps in its conquering talons all that belongs to us; for we do not, in life, make any great difference between what is _we_ and what is_ours_--an insult to our dog, our dwelling, or our work wounds us asmuch as an insult to ourselves. The possessive pronoun expresses bothpossession and possessor. In fact, we consider our body as beingourselves. Here, then, are numbers of material things introducing themselves intothe category of mental things. If we wished to expel them and toreduce the domain of the Ego to the domain of the mental, we couldonly do so if we already possessed the criterion of what isessentially mental. The notion of the Ego cannot therefore supply uswith this criterion. Another opinion consists in making of the subject a spiritualsubstance, of which the consciousness becomes a faculty. By substanceis understood an entity which possesses the two following principalcharacteristics, unity and identity, this latter merging into unity, for it is nothing else but the persistence of unity through the courseof time. Certain philosophers have asserted that through intuition wecan all establish that we are a spiritual substance. I am compelled toreject this idea, because I think the expression _spiritual substance_has no meaning; nothing but the sonorous value of six syllables. Ithas also been supposed, that there exists a corporeal substance hiddenunder the sensations, in which are implanted the qualities of bodies, as the various organs of a flower are in its calyx. I will returnlater to this conception of a material substance. That of a spiritualsubstance cannot be defended, and the chief and fatal argument I urgeagainst it is, that we cannot represent it to our minds, we cannotthink it, and we cannot see in these words "spiritual substance" anyintelligible idea; for that which is mental is limited to "that whichis of the consciousness. " So soon as we endeavour to go beyond thefact of having consciousness to imagine a particular state which mustbe mental, one of two things happen; either we only grasp the void, orelse we construct a material and persistent object in which werecognise psychical attributes. These are two conclusions which oughtto be rejected. FOOTNOTES: [Footnote 23: This second method of expression, which I considerinexact, is constantly found in DESCARTES. Different philosophers haveexplicitly admitted that every act of cognition implies a relationsubject-object. This is one of the corner-stones of the neo-criticismof RENOUVIER. He asserts that all representation is double-faced, andthat what is known to us presents itself in the character of bothrepresentative and represented. He follows this up by describingseparately the phenomena and laws of the representative and of therepresented respectively. ] [Footnote 24: The preceding ten lines in the text I wrote afterreading a recent article of WILLIAM JAMES, who wishes to show that theconsciousness does not exist, but results simply from the relation orthe opposition raised between one part of our experience (the actualexperience, for instance, in the example of the perception of anobject) and another part, the remembrance of our person. But theargument of JAMES goes too far; he is right in contesting the relationsubject-object, but not in contesting the existence of theconsciousness (W. JAMES: "Does consciousness exist?" in _J. OfPhilosophy, &c. _, Sept. 1904). ] CHAPTER VI DEFINITION OF THE CONSCIOUSNESS--CATEGORIES OF THE UNDERSTANDING It has often been said that the rôle of intelligence consists inuniting or grasping the relations of things. An important question, therefore, to put, is, if we know whereof these relations consist, andwhat is the rôle of the mind in the establishment of a relation? It now and then happens to us to perceive an isolated object, withoutcomparing it with any other, or endeavouring to find out whether itdiffers from or resembles another, or presents with any other arelation of cause to effect, or of sign to thing signified, or ofco-existence in time and space. Thus, I may see a red colour, andoccupy all the intellect at my disposal in the perception of thiscolour, seeing nothing but it, and thinking of nothing but it. Theoretically, this is not impossible to conceive, and, practically, Iask myself if these isolated and solitary acts of consciousness do notsometimes occur. It certainly seems to me that I have noticed in myself moments ofintellectual tonelessness, when in the country, during the vacation, I look at the ground, or the grass, without thinking of anything--orat least, of anything but what I am looking at, and without comparingmy sensation with anything. I do not think we should admit inprinciple, as do many philosophers, that "we take no cognisance saveof relations. " This is the _principle of relativity_, to which so muchattention has been given. Taken in this narrow sense, it seems to mein no way imperative for our thoughts. We admit that it is very oftenapplied, but without feeling obliged to admit that it is of perpetualand necessary application. These reserves once made, it remains to remark, that the objects weperceive very rarely present themselves in a state of perfectisolation. On the contrary, they are brought near to other objects bymanifold relations of resemblance, of difference, or of connection intime or space; and, further, they are compared with the ideas whichdefine them best. We do not have consciousness of an object, but ofthe relations existing between several objects. Relation is the newstate produced by the fact that one perceives a plurality of objects, and perceives them in a group. Show me two colours in juxtaposition, and I do not see two coloursonly, but, in addition, their resemblance in colour or value. Show metwo lines, and I do not see only their respective lengths but theirdifference in length. Show me two points marked on a white sheet ofpaper, and I do not see only the colour, form, and dimension of thepoints, but their distance from each other. In our perceptions, as inour conceptions, we have perpetually to do with the relations betweenthings. The more we reflect, the more we understand things, the moreclearly we see their relations; the multiplication of relations is themeasure of the depth of cognition. [25] The nature of these relations is more difficult to ascertain than thatof objects. It seems to be more subtle. When two sounds makethemselves heard in succession, there is less difficulty in making thenature of these two sounds understood than the nature of the fact thatone occurs before the other. It would appear that, in the perceptionof objects, our mind is passive and reduced to the state of reception, working like a registering machine or a sensitive surface, while inthe perception of relations it assumes a more important part. Two principal theories have been advanced, of which one puts therelations in the things perceived, and the other makes them a work ofthe mind. Let us begin with this last opinion. It consists insupposing that the relations are given to things by the mind itself. These relations have been termed categories. The question ofcategories plays an important part in the history of philosophy. Threegreat philosophers, Aristotle, Kant, and Renouvier have drawn up alist, or, as it is called, a table of them, and this table is verylong. To give a slight idea of it, I will quote a few examples, suchas time, space, being, resemblance, difference, causality, becoming, finality, &c. By making the categories the peculiar possession of the mind, weattribute to these cognitions the essential characteristic of beinganterior to sensation, or, as it is also termed, of existing _apriori_: we are taught that not only are they not derived fromexperience, nor taught us by observation, but further that they arepresupposed by all observation, for they set up, in scholastic jargon, the conditions which make experience possible. They represent thepersonal contribution of the mind to the knowledge of nature, and, consequently, to admit them is to admit that the mind is not, in thepresence of the world, reduced to the passive state of a _tabularasa_, and that the faculties of the mind are not a transformation ofsensation. Only these categories do not supplement sensation, they donot obviate it, nor allow it to be conjectured beforehand. They remainempty forms so long as they are not applied to experience; they arethe rules of cognition and not the objects of cognition, the means ofknowing and not the things known; they render knowledge possible, butdo not of themselves constitute it, Experience through the sensesstill remains a necessary condition to the knowledge of the externalworld. It may be said that the senses give the matter of knowledge, and that the categories of the understanding give the form of it. Matter cannot exist without form, nor form without matter; it is theunion of the two which produces cognition. Such is the simplest idea that can be given of the Kantian theory ofcategories, or, if it is preferred to employ the term often used andmuch discussed, such is the theory of the Kantian idealism, Thistheory, I will say frankly, hardly harmonises with the ideas I haveset forth up to this point. To begin with, let us scrutinise therelation which can exist between the subject and the object. We haveseen that the existence of the subject is hardly admissible, for itcould only be an object in disguise. Cognition is composed in realityof an object and an act of consciousness. Now, how can we know if thisact of consciousness, by adding itself to the object, modifies it andcauses it to appear other than it is? This appears to me an insoluble question, and probably, even, afactitious one. The idea that an object can be modified in its natureor in its aspect comes to us through the perception of bodies. We seethat, by attacking a metal with acids, this metal is modified, andthat by heating a body its colour and form become changed; or that byelectrifying a thread it acquires new properties; or that when weplace glasses before our eyes we change the visible aspect of objects;or that, if we have inflammation of the eyelids, light is painful, andso on. All these familiar experiments represent to us the variedchanges that a body perceived can undergo; but it must be carefullyremarked that in cases of this kind the alteration in the body isproduced by the action of a second body, that the effect is due to anintercourse between two objects. On the contrary, when we take theKantian hypothesis, that the consciousness modifies that which itperceives, we are attributing to the consciousness an action which hasbeen observed in the case of the objects, and are thus transportinginto one domain that which belongs to a different one; and we arefalling into the very common error which consists in losing sight ofthe proper nature of the consciousness and making out of it an object. If we set aside this incorrect assimilation, there no longer remainsany reason for refusing to admit that we perceive things as they are, and that the consciousness, by adding itself to objects, does notmodify them. Phenomena and appearances do not, then, strictly speaking, exist. Tillproof to the contrary, we shall admit that everything we perceive isreal, that we perceive things always as they are, or, in other words, that we always perceive _noumena_. [26] After having examined the relations of the consciousness with itsobjects, let us see what concerns the perception, by theconsciousness, of the relations existing between these objectsthemselves. The question is to ascertain whether the _a priorists_ areright in admitting that the establishment of these relations is thework of the consciousness. The rôle of synthetic power that is thusattributed to consciousness is difficult to conceive unless we alterthe definition of consciousness to fit the case. In accordance withthe definition we have given and the idea we have of it, theconsciousness makes us acquainted with what a thing is, but it addsnothing to it. It is not a power which begets objects, nor is it apower which begets relations. Let us carefully note the consequence at which we should arrive, if, while admitting, on the one hand, that our consciousness lights up andreveals the objects without creating them, we were, on the other hand, to admit that it makes up for this passivity by creating relationsbetween objects. We dare not go so far as to say that this creation ofrelations is arbitrary and corresponds in no way to reality; or that, when we judge two neighbouring or similar objects, the relations ofcontiguity and resemblance are pure inventions of our consciousness, and that these objects are really neither contiguous nor similar. It must therefore be supposed that the relation is already, in somemanner, attracted into the objects; it must be admitted that ourintelligence does not apply its categories haphazard or from thecaprice of the moment; and it must be admitted that it is led to applythem because it has perceived in the objects themselves a sign and areason which are an invitation to this application, and itsjustification. On this hypothesis, therefore, contiguity andresemblance must exist in the things themselves, and must beperceived; for without this we should run the risk of finding similarthat which is different, and contiguous that which has no relation oftime or space. Whence it results, evidently, that our consciousnesscannot create the connection completely, and then we are greatlytempted to conclude that it only possesses the faculty of perceivingit when it exists in the objects. [27] According to this conception, the rôle of the consciousness in theperception of a connection is that of a witness, as in the perceptionof objects. The consciousness does not create, but it verifies. Resemblance is a physical property of objects, like colour; andcontiguity is a physical property of objects, like form. Theconnections between the objects form part of the group object and notof the group consciousness, and they are just as independent ofconsciousness as are the objects themselves. Against this conclusion we must anticipate several objections. One ofthem will probably consist in accentuating the difference existingbetween the object and the connection from the dynamical point ofview. That the object may be passively contemplated by theconsciousness can be understood, it will be said; but the relation isnot only an object of perception--it is, further, a principle ofaction, a power of suggestion, and an agent of change. It might, then, he supposed that the consciousness here finds acompensation for the rôle that has been withdrawn from it. If it isnot the thing that creates the relation, it will be said, at least itis that which creates its efficacity of suggestion. Many psychologistshave supposed that a relation has the power of evocation only when ithas been perceived. The perception of resemblance precedes the actionof resemblance. It is consequently the consciousness which assemblesthe ideas and gives them birth by perceiving their relations. This error, for it is one, has long been wide-spread--indeed, it stillpersists. [28] We have, however, no difficulty in understanding thatthe perception of a resemblance between two terms supposes them to beknown; so long as only one of the terms is present to theconsciousness, this perception does not exist; it cannot thereforepossess the property of bringing to light the second term. Suggestionis therefore distinct from recognition; it is when suggestion hasacted, when the resemblance in fact has brought the two termstogether, that the consciousness, taking cognisance of the workaccomplished, verifies the existence of a resemblance, and that thisresemblance explains the suggestion. Second objection: we are told that the relations between theobjects--that is, the principal categories--must be of a mentalnature, because they are _a priori_. That they are _a priori_ meansthat they are at once anterior and superior to the experience. Let ussee what this argument is worth. It appears that it is somewhat misused. With regard to many of thecategories, we are content to lay down the necessity of an abstractidea in order to explain the comprehension of a concrete one. It issaid, for example: how can it be perceived that two sensations aresuccessive, if we do not already possess the idea of time? Theargument is not very convincing, because, for every kind of concreteperception it is possible to establish an abstract category. It might be said of colour that it is impossible to perceive it unlessit is known beforehand what colour is; and so on for a heap of otherthings. A more serious argument consists in saying that relations are_a priori_ because they have a character of universality and ofnecessity which is not explained by experience, this last being alwayscontingent and peculiar. But it is not necessary that a functionshould be mental for it to be _a priori_. The identification of the _apriori_ with the mental is entirely gratuitous. We should here draw adistinction between the two senses of the _a priori_: anteriority andsuperiority. A simple physical mechanism may be _a priori_, in the sense ofanteriority. A house is _a priori_, in regard to the lodgers itreceives; this book is _a priori_, in regard to its future readers. There is no difficulty in imagining the structure of our nervoussystem to be _a priori_, in regard to the excitements which arepropagated in it. A nerve cell is formed, with its protoplasm, itsnucleus and its nucleoli before being irritated; its propertiesprecede its functions. If it be possible to admit that as aconsequence of ancestral experiences the function has created theorgan, the latter is now formed, and this it is which in its turnbecomes anterior to the function. The notion of _a priori_ hastherefore nothing in it which is repugnant to physical nature. Let us now take the _a priori_ in the sense of superiority. Certainjudgments of ours are, we are told, universal and necessary, andthrough this double character go beyond the evidence of experience. This is an exact fact which deserves to be explained, but it is notindispensable to explain it by allowing to the consciousness a sourceof special cognitions. The English school of philosophy have alreadyattacked this problem in connection with the origin of axioms. Theprinciple of their explanation lies in the virtue of what they havetermed "inseparable association. " They have supposed that when anassociation is often repeated it creates a habit of thought againstwhich no further strife is possible. The mechanism of associationitself should then add a special virtue to the contingency of facts. Ahundred repetitions of related facts, for example, would give rise toso firm an association, that no further repetition would increase it. I consider this explanation a very sound one in principle. It is rightto put into association something more than into experience. I wouldonly suggest a slight correction in detail. It is not the associationforged by repetition which has this virtue of conveying the idea ofnecessity and universality, it is simply the uncontradictedassociation. It has been objected, in fact, and with reason, to thesolution of Mill, that it insists on a long duration of experience, while axioms appear to be of an irresistible and universaltruthfulness the moment they are conceived. And this is quite just. Ishould prefer to lay down as a law that every representation appearstrue, and that every link appears necessary and universal as soon asit is formed. This is its character from the first. It preserves it solong as no contradiction in fact, in reasoning, or in idea, comes todestroy it. [29] What seems to stand out most clearly after all these explanations isthe rôle which we ought to attribute to the consciousness. Two rivaltheories have been maintained: that of the mirror-consciousness andthat of the focus-consciousness. It would seem--I merely say it wouldseem--that the first of these best harmonises with the precedingfacts. For what seems most probable is, that the consciousnessilluminates and reveals but does not act. The theory of thefocus-consciousness adapts itself less to the mechanism of theassociation of ideas. From this we come quite naturally to see in the intelligence only aninactive consciousness; at one moment it apprehends an object, and itis a perception or an idea; at another time it perceives a connection, and it is a judgment; at yet another, it perceives connections betweenconnections, and it is an act of reason. But however subtle the objectit contemplates may become, it does not depart from its contemplativeattitude, and cognition is but a consciousness. One step further, and we should get so far as to admit that theconsciousness serves no purpose whatever, and that it is a uselessluxury, since, if all efficacious virtue is to be found in thesensations and the ideas which we consider as material facts, theconsciousness which reveals them adds nothing to, takes nothing fromand modifies nothing in them; and everything would go on the same, norwould anything in this world be changed, if one day the light ofconsciousness were, by chance, to be put out. We might imagine acollection of automatons forming a human society as complicated as, and not different in appearance from, that of conscious beings; theseautomatons would make the same gestures, utter the same words asourselves, would dispute, complain, cry, and make love like us; wemight even imagine them capable, like us, of psychology. This is thethesis of the epiphenomenal consciousness which Huxley has boldlycarried to its uttermost conclusions. I indicate here these possible conclusions, without discussing them. It is a question I prefer to leave in suspense; it seems to me thatone can do nothing on this subject but form hypotheses. FOOTNOTES: [Footnote 25: At the risk of being deemed too subtle, I ask whether weare conscious of a relation between objects, or whether that whichoccurs is not rather the perception of an object which has beenmodified in its nature by its relation with another object. ] [Footnote 26: This conclusion may seem contradictory to that which Ienunciated when studying the constitution of matter. I then assertedthat we only know our sensations and not the excitants which producethem. But these sensations are matter; they are matter modified byother matter, viz. Our nervous centres. We therefore take up very distinctly an opposite standpoint to theprinciple of _relativity_: in other terms, we reject the phenomenismof Berkeley. When we go into metaphysics we are continually astounded to see howdifferent conceptions of things which have a classic value areindependent of each other. In general, phenomenism is opposed tosubstantialism, and it is supposed that those who do not accept theformer doctrine must accept the latter, while, on the contrary, thosewho reject substantialism must be phenomenists. We know that it is inthis manner that Berkeley conquered corporeal substantialism andtaught phenomenism; while Hume, more radical than he, went so far asto question the substantialism of mind. On reflection, it seems to methat, after having rejected phenomenism, we are in no way constrainedto accept substance. By saying that we perceive things as they are, and not through a deluding veil, we do not force ourselves toacknowledge that we perceive the substance of bodies--that is to say, that something which should be hidden beneath its qualities and shouldbe distinct from it. The distinction between the body and itsqualities is a thing useful in practice, but it answers to noperception or observation. The body is only a group, a sheaf ofqualities. If the qualities seem unable to exist of themselves and torequire a subject, this is only a grammatical difficulty, which is dueto the fact that, while calling certain sensations qualities, wesuppose a subject to be necessary. On the other hand, therepresentation which we make to ourselves of a material substance andits rôle as the support of the qualities, is a very naïve andmechanical representation, thanks to which certain sensations becomethe supports of other and less important sensations. It would sufficeto insist on the detail of this representation and on its origin toshow its artificial character. The notion we have of the stability ofbodies and of the persistence of their identity, notwithstandingcertain superficial changes, is the reason for which I thought properto attribute a substance to them, that is to say, an invariableelement. But we can attain the same end without this uselesshypothesis; we have only to remark that the identity of the objectlies in the aggregate of its properties, including the name it bears. If the majority of its properties, especially of those most importantto us, subsists without alteration, or if this alteration, though ofvery great extent, takes place insensibly and by slow degrees, wedecide that the object remains the same. We have no need for thatpurpose to give it a substance one and indestructible. Thus we areneither adherents of phenomenism, nor of substantialism. ] [Footnote 27: I borrow from RABIER this argument, which has thoroughlyconvinced me (see _Psychologie_, p. 281). ] [Footnote 28: PILON is the psychologist who has the most forciblydemonstrated that resemblance acts before being perceived. I refer thereaders to my _Psychologie du Raisonnement_, where I have set forththis little problem in detail. ] [Footnote 29: We think spontaneously of the general and the necessary. It is this which serves as a basis for the suggestion and thecatchword (_réclame_), and it explains how minds of slender culturealways tend towards absolute assertions and hasty generalisations. ] CHAPTER VII DEFINITION OF THE CONSCIOUSNESS--THE SEPARABILITY OF THE CONSCIOUSNESSFROM ITS OBJECT--DISCUSSION OF IDEALISM One last question suggests itself with regard to the consciousness. Inwhat measure is it separable from the object? Do the consciousness andits object form two things or only one? Under observation these two terms constantly show themselves united. We experience a sensation and have consciousness of it; it is the samefact expressed in two different ways. All facts of our perception thuspresent themselves, and they are one. But our reason may outstrip ourobservation. We are able to make a distinction between the twoelements _being_ and _being perceived_. This is not an experimentalbut an ideological distinction, and an abstraction that language makeseasy. Can we go further, and suppose one of the parts thus analysed capableof existing without the other? Can sensation exist as physicalexpression, as an object; without being illuminated by theconsciousness? Can the consciousness exist without having an object? Let us first speak of the existence of the object when considered asseparated from the consciousness. The problem is highly complicated. It has sometimes been connected with the idealist thesis according towhich the object of consciousness, being itself a modality of theconsciousness, cannot exist apart from it--that is to say, outside theperiods in which it is perceived. It would therefore result from thisthat this separation between existence and perception might be made, when it is admitted (contrary to the idealist hypothesis) that theobject perceived is material and the consciousness which perceives itmental. In this case, it will be thought, there is no link ofsolidarity between the consciousness and its continuity. But I am notof that opinion. The union of the consciousness and its object is oneof fact, which presents itself outside any hypothesis on the nature ofthe object. It is observation which demonstrates to us that we mustperceive an object to be assured of its existence; the reason, moreover, confirms the necessity of this condition, which remains truewhatever may be the "stuff" of the object. Having stated this, the question is simply to know whether thisobservation of fact should be generalised or not. We may, it seems tome, decline to generalise it without falling into a contradiction interms. It may be conceived that the objects which we are looking atcontinue to exist, without change, during the moments when we havelost sight of them. This seems reasonable enough, and is the opinionof "common" sense. [30] The English philosophers, Bain and Mill, have combated thisproposition with extraordinary ardour, like believers combating aheresy. But notwithstanding their attacks it remains intelligible, andthe distinction between _being_ and _being perceived_ preserves itslogical legitimacy. This may be represented, or may be thought; butcan it be realised? So far as regards external objects, I think we all, in fact, admit it. We all admit a distinction, between the existence of the outer worldand the perception we have of it; its existence is one thing, and ourperception of it is another. The existence of the world continueswithout interruption; our perception is continually interrupted by themost fortuitous causes, such as change of position, or even theblinking of the eyes; its existence is general, universal, independentof time and space; our perception is partial, particular, local, limited by the horizon of our senses, determined by the geographicalposition of our bodies, riddled by the distractions of ourintelligence, deceived by the illusions of our minds, and above alldiminished by the infirmity of our intelligence, which is able tocomprehend so little of what it perceives. This is what we all admitin practice; the smallest of our acts implies the belief in somethingperceptible which is wider and more durable than our astonishedperceptions. I could not write these lines unless I implicitlysupposed that my inkstand, my paper, my pen, my room, and thesurrounding world subsist when I do not see them. It is a postulate ofpractical life. It is also a postulate of science, which requires forits explanations of phenomena the supposition in them of an indwellingcontinuity. Natural science would become unintelligible if we wereforced to suppose that with every eclipse of our perceptions materialactions were suspended. There would be beginnings without sequences, and ends without beginnings. Let us note also that acquired notions on the working of our nervoussystem allow us to give this postulate a most precise form: theexternal object is distinct from the nervous system and from thephenomena of perception which are produced when the nervous system isexcited; it is therefore very easy to understand that this objectcontinues to exist and to develop its properties, even when no brainvibrates in its neighbourhood. Might we not, with the view of strengthening this conclusion as tothe continuous existence of things, dispense with this postulate, which seems to have the character of a grace, of an alms granted tous? Might not this continuous existence of objects during the eclipsesof our acts of consciousness, be demonstrated? It does not seem to meimpossible. Let us suppose for a moment the correctness of theidealist thesis: all our legitimate knowledge of objects is containedwithin the narrow limits of actual sensation; then, we may ask, ofwhat use is the reason? What is the use of the memory? These functionshave precisely for their object the enlarging of the sphere of oursensations, which is limited in two principal ways, by time and byspace. Thanks to the reason, we manage to see in some way that whichour senses are unable to perceive, either because it is too distantfrom us, or because there are obstacles between us and the object, orbecause it is a past event or an event which has not yet taken placewhich is in question. That the reason may be deceived is agreed. But will it be assertedthat it is always deceived? Shall we go so far as to believe that thisis an illegitimate mode of cognition? The idealist thesis, ifconsistent, cannot refuse to extend itself to this extreme conclusion;for a reasoned conclusion contains, when it has a meaning, a certainassertion on the order of nature, and this assertion is not aperception, since its precise object is to fill up the gaps in ourperceptions. Not being a perception, it must be rejected, if one is anidealist. The idealist will therefore keep strictly to the perception of themoment, and this is so small a thing when deprived of all theconjectures which enrich it, that the world, if reduced to this alone, would be but the skeleton of a world. There would then be no morescience, no possibility of knowledge. But who could make up his mindthus to shut himself up in perception? I suppose, indeed, that there will here be quibbling. This objectionwill be made: that in the hypothesis of a discontinuous existence ofthings, reason may continue to do its work, provided the interventionof a possible perception be supposed. Thus, I notice this morning, ongoing into my garden, that the pond which was dry yesterday is full ofwater. I conclude from this, "It has rained in the night. " To beconsistent with idealism, one must simply add: "If some one had beenin the garden last night, he would have seen it rain. " In this mannerone must re-establish every time the rights of perception. Be it so. But let us notice that this addition has no more importancethan a prescribed formula in a notarial act; for instance, thepresence of a second notary prescribed by the law, but alwaysdispensed with in practice. This prescribed formula can always beimagined or even understood. We shall be in accord with idealism bythe use of this easy little formula, "If some one had been there, " oreven by saying, "For a universal consciousness. .. . " The difference ofthe realist and idealist theory becomes then purely verbal. Thisamounts to saying that it disappears. But there is always muchverbalism in idealism. One more objection: if this witness--the consciousness--suffices togive objects a continuity of existence, we may content ourselves witha less important witness. Why a man? The eyes of a mollusc wouldsuffice, or those of infusoria, or even of a particle of protoplasm:living matter would become a condition of the existence of deadmatter. This, we must acknowledge, is a singular condition, and thisconclusion condemns the doctrine. FOOTNOTES: [Footnote 30: That is to say, the sense of the multitude. --ED. ] CHAPTER VIII DEFINITION OF THE CONSCIOUSNESS--THE SEPARATION OF THE CONSCIOUSNESSFROM ITS OBJECT--THE UNCONSCIOUS I ask myself whether it is possible, by going further along this roadof the separation between the consciousness and its object, to admitthat ideas may subsist during the periods when we are not conscious ofthem. It is the problem of unconsciousness that I am here stating. One of the most simple processes of reasoning consists in treatingideas in the same manner as we have treated the external objects. Wehave admitted that the consciousness is a thing superadded to theexternal objects, like the light which lights up a landscape, but doesnot constitute it and may be extinguished without destroying it. Wecontinue the same interpretation by saying that ideas prolong theirexistence while they are not being thought, in the same way and forthe same motive that material bodies continue theirs while they arenot being perceived. All that it seems permissible to say is that thisconception is not unrealisable. Let us now place ourselves at the point of view of the consciousness. We have supposed up to the present the suppression of theconsciousness, and have seen that we can still imagine the objectcontinuing to exist. Is the converse possible? Let us suppose that theobject is suppressed. Can the consciousness then continue to exist? Onthis last point it seems that doubt is not possible, and we mustanswer in the negative. A consciousness without an object, an emptyconsciousness, in consequence, cannot be conceived; it would be azero--a pure nothingness; it could not manifest itself. We mightadmit, in strictness, that such a consciousness might exist virtuallyas a power which is not exercised, a reserve, a potentiality, or apossibility of being; but we cannot comprehend that this power canrealise or actualize itself. There is therefore no actualconsciousness without an object. The problem we have just raised, that of the separability of theelements which compose an act of consciousness, is continued byanother problem--that of unconsciousness. It is almost the sameproblem, for to ask one's self what becomes of a known thing when weseparate from it the consciousness which at first accompanied it, isto ask one's self in what an unconscious phenomenon consists. We have, till now, considered the two principal forms ofunconsciousness--that in nature and that in thought. The first namedunconsciousness does not generally bear that name, but is ratherdiscussed under the name of idealism and realism. Whatever be theirnames, these two kinds of unconsciousness are conceivable, and themore so that they both belong to physical nature. If we allow ourselves to be guided by the concept of separability, weshall now find that we have exhausted the whole series of possibleproblems, for we have examined all the possible separations betweenthe consciousness and its objects; but if we use another concept, thatof unconsciousness, we can go further and propound a new problem: canthe consciousness become unconscious? But it is proper first to make afew distinctions. It is the rôle of metaphysics to makedistinctions. [31] Unconsciousness presupposes a death of the consciousness; but thisdeath has its degrees, and before complete extinction we may conceiveit to undergo many attenuations. There is, first, the diminution ofconsciousness. Consciousness is a magnitude capable of increase and decrease, likesensation itself. According to the individual, consciousness may havea very large or a very small field, and may embrace at the same time avariable number of objects. I can pay attention to several things atthe same time, but when I am tired it becomes more difficult to me. Ilose in extension, or, as is still said, the field of consciousness isrestricted. It may also lose not only in extent of surface, but indepth. We have all of us observed in our own selves moments of obscureconsciousness when we understand dimly, and moments of luminousconsciousness which carry one almost to the very bottom of things. Itis difficult to consider those in the wrong who admit, with Leibnitz, the existence of small states of consciousness. The lessening of theconsciousness is already our means of understanding the unconscious;unconsciousness is the limit of this reduction. [32] This singular fact has also been noticed, that, in the same individualthere may co-exist several kinds of consciousness which do not enterinto communication with each other and which are not acquainted witheach other. There is a principal consciousness which speaks, and, inaddition, accessory kinds of consciousness which do not speak, butreveal their existence by the use of other modes of expression, ofwhich the most frequent is writing. This doubling or fractionation of the consciousness and personalityhave often been described in the case of hysterical subjects. Theysometimes occur quite spontaneously, but mostly they require a littlesuggestion and cultivation. In any case, that they are produced in oneway or other proves that they are possible, and, for the theory, thispossibility is essential. Facts of this kind do not lead to a theoryof the unconscious, but they enable us to understand how certainphenomena, unconscious in appearance, are conscious to themselves, because they belong to states of consciousness which have beenseparated from each other. A third thesis, more difficult of comprehension than the other two, supposes that the consciousness may be preserved in an unconsciousform. This is difficult to admit, because unconsciousness is thenegation of consciousness. It is like saying that light can bepreserved when darkness is produced, or that an object still existswhen, by the hypothesis, it has been radically destroyed. This ideaconveys no intelligible meaning, and there is no need to dwell on it. We have not yet exhausted all the concepts whereby we may get tounconsciousness. Here is another, the last I shall quote, without, however, claiming that it is the last which exists. We might call itthe physiological concept, for it is the one which the physiologistsemploy for choice. It is based upon the observation of the phenomenawhich are produced in the nervous system during our acts ofconsciousness; these phenomena precede consciousness as a rule, andcondition it. According to a convenient figure which has been long inuse, the relations of the physiological phenomenon to theconsciousness are represented as follows: the physiological phenomenonconsists in an excitement which, at one time, follows a direct andshort route from the door by which it enters the nervous system to thedoor by which it makes its exit. In this case, it works like a simplemechanical phenomenon; but sometimes it makes a longer journey, andtakes a circuitous road by which it passes into the higher nervecentres, and it is at the moment when it takes this circuitous roadthat the phenomenon of consciousness is produced. The use of thisfigure does not prejudge any important question. Going further, many contemporary authors do not content themselveswith the proposition that the consciousness is conditioned by thenervous phenomenon, but suggest also that it is continuallyaccompanied by it. Every psychical fact of perception, of emotion, orof idea should have, it is supposed, a physiological basis. It wouldtherefore be, taken in its entirety, psycho-physiological. This iscalled the parallelist theory. We cannot discuss this here, as we shall meet with it again in thethird part of this book. It has the advantage of leading to a verysimple definition of unconsciousness. The unconscious is that which ispurely physiological. We represent to ourselves the mechanical part ofthe total phenomenon continuing to produce itself, in the absence ofthe consciousness, as if this last continued to follow and illuminateit. Such are the principal conceptions that may be formed of theunconscious. They are probably not the only ones, and our list is notexhaustive. After having indicated what the unconscious is, we will terminate bypointing out what it is not and what it cannot be. We think, or at least we have impliedly supposed in the precedingdefinitions, that the unconscious is only something unknown, which mayhave been known, or which might become known under certain conditions, and which only differs from the known by the one characteristic of notbeing actually known. If this notion be correct, one has really notthe right to arm this unconsciousness with formidable powers. It hasthe power of the reality to which it corresponds, but its characterof unconsciousness adds nothing to this. It is the same with it aswith the science of the future. No scholar will hesitate to admit thatthat science will be deeper and more refined than that already formed. But it is not from the fact that it is unknown that it will deserveits superiority: it is from the phenomena that it will embrace. Togive to that which is unconscious, as we here understand it, anoverwhelming superiority over the conscious as such, we must admitthat the consciousness is not only a useless luxury, but thedethronement of the forces that it accompanies. In the next place, I decline to admit that the consciousness itselfcan become unconscious, and yet continue in some way under anunconscious form. This would be, in my opinion, bringing together twoconceptions which contradict each other, and thus denying after havingaffirmed. From the moment that the consciousness dies, there remainsnothing of it, unless it be the conditions of its appearance, conditions which are distinct from itself. Between two moments ofconsciousness separated by time or by a state of unconsciousness, there does not and cannot exist any link. I feel incapable ofimagining of what this link could be composed, unless it werematerial--that is to say, unless it were supplied from the class ofobjects. I have already said that the substantialist thesisendeavours to establish a continuity between one consciousness andanother separated by time, by supposing a something durable, of whichthe consciousness would be a property of intermittent manifestation. They would thus explain the interruptions of consciousness as theinterruptions in the light of a lamp. When the light is extinguished, the lamp remains in darkness, but is still capable of being lighted. Let us discard this metaphor, which may lead to illusion. The conceptof consciousness can furnish no link and no mental state which remainswhen the consciousness is not made real; if this link exists, it is inthe permanence of the material objects and of the nervous organismwhich allows the return of analogous conditions of matter. FOOTNOTES: [Footnote 31: In metaphysics we reason, not on facts, but most oftenon conceptions. Now just as facts are precise so conceptions are vaguein outline. Facts are like crystallised bodies, ideas like liquids andgases. We think we have an idea, and it changes form without ourperceiving it. We fancy we recognise one idea, and it is but another, which differs slightly from the preceding one. By means ofdistinctions we ought to struggle against this flowing away and flightof ideas. ] [Footnote 32: I think I have come across in ARISTOTLE the ingeniousidea that the enfeeblement of the consciousness and its disorder maybe due to the enfeeblement and disorder of the object. It is a theorywhich is by no means improbable. ] CHAPTER IX DEFINITIONS OF PSYCHOLOGY Let us resume the study of the preceding ideas in another form. Since, moreover, to define mind is at the same time to define psychology, letus seek for the truth which we can glean from the definitions of thisscience. Our object is not to discover an exact definition, but tomake use of those already existing. To define psychology is to describe the features of the domain overwhich this science holds sway, and at the same time to indicate theboundaries which separate it from its neighbours. At first sight thisis an affair of geometric survey, presenting no kind of difficulty;for psychology does not merge by insensible transitions into theneighbouring sciences, as physics does with chemistry, for example, orchemistry with biology. To all the sciences of external nature psychology offers the violentopposition of the moral to the physical world. It cannot be put inline with the physical sciences. It occupies, on the contrary, aposition apart. It is the starting point, the most abstract and simpleof the moral sciences; and it bears the same relation to them thatmechanics does to the physical. All this is doubtless true; and yet a very great difficulty has beenexperienced in condensing into a clear definition the essence ofpsychology. This is proved by the multiplicity of definitionsattempted. They are so many because none of them has proved completelysatisfactory. Their abundance shows their insufficiency. I will try tointroduce a little order into these attempts, and propose todistribute the definitions of psychology into the followingcategories:-- 1. The definition by substance; the metaphysical definition _par excellence_. 2. The definition by enumeration. 3. " " method. 4. " " degree of certainty. 5. " " content. 6. " " point of view. 7. " " the peculiar nature of mental laws. We will rapidly run through this series of efforts at definition, andshall criticise and reject nearly the whole of them; for the lastalone seems exact--that is to say, in harmony with the ideas laid downabove. Metaphysical definition has to-day taken a slightly archaistic turn. Psychology used to be considered as the _science of the soul_. Thisis quite abandoned. Modern authors have adopted the expression andalso the idea of Lange, [33] who was, I think, the first to declarethat we ought to cultivate a _soulless psychology_. This categoricaldeclaration caused an uproar, and a few ill-informed personsinterpreted it to mean that the new psychology which has spread inFrance under cover of the name of Ribot, sought to deny the existenceof the soul, and was calculated to incline towards materialism. Thisis an error. It is very possible, indeed, that several adepts of the new orexperimental psychology may be materialists from inward conviction. The exclusive cultivation of external facts, of phenomena termedmaterial, evidently tends--this is a mystery to none--to incline themind towards the metaphysical doctrine of materialism. But, aftermaking this avowal, it is right to add at once that psychology, as ascience of facts, is the vassal of no metaphysical doctrine. It isneither spiritualist, materialist, nor monist, but a science of factssolely. Ribot and his pupils have proclaimed this aloud at everyopportunity. Consequently it must be recognised that the ratheramphibological expression "soulless psychology" implies no negation ofthe existence of the soul. It is--and this is quite a differentthing--rather an attitude of reserve in regard to this problem. We donot solve this problem; we put it on one side. And, certainly, we are right to do so. The soul, viewed as asubstance--that is, as a something distinct from psychical phenomena, which, while being their cause and support, yet remains inaccessibleto our direct means of cognition--is only an hypothesis, and it cannotserve as objective to a science of facts. This would imply acontradiction in terms. Unfortunately; we must confess that if it be right to relegate tometaphysics the discussion on the concept of the soul, it does notreally suffice to purge our minds of all metaphysics; and a person whobelieves himself to be a simple and strict experimentalist is often ametaphysician without knowing it. These excommunications ofmetaphysics also seem rather childish at the present day. There isless risk than some years ago in declaring that: "Here metaphysicscommence and positive science ends, and I will go no further. " Thereis even a tendency in modern psychologists to interest themselves inthe highest philosophical problems, and to take up a certain positionwith regard to them. The second kind of definition is, we have said, that by enumeration. It consists in placing before the eyes of the reader an assortment ofpsychological phenomena and then saying: "These are the thingspsychology studies. " One will take readily as samples the ideas, reasonings, emotions, and other manifestations of mental life. If thisis only a strictly provisional definition, a simple introduction tothe subject, we accept it literally. It may serve to give us a firstimpression of things, and to refresh the memories of those who, by arather extraordinary chance, would not doubt that psychology studiesour thoughts. But whatever may be the number of these deeply ignorantpersons, they constitute, I think, a negligible quantity; and, afterthese preliminaries, we must come to a real definition and not jugglewith the problem, which consists in indicating in what the spiritualis distinguished from the material. Let us leave on one side, therefore, the definitions by enumeration. Now comes the definition by method. Numbers of authors have supposedthat it is by its method that psychology is distinguished from theother sciences. To the mind is attached the idea of the within, to nature the idea ofbeing without the mind, of constituting a "without" (_un dehors_). Itis a vague idea, but becomes precise in a good many metaphors, and hasgiven rise to several forms of speech. Since the days of Locke, wehave always spoken of the internal life of the mind as contrastedwith the external life, of subjective reality as contrasted withobjective reality; and in the same way we oppose the external sensesto the inner sense (the internal perception), which it has at timesbeen proposed to erect into a sixth sense. Though no longer quite theCartesian dualism, this is still a dualism. It has also been said that psychology is the science of introspection, and, in addition, that scientific psychology is a controlledintrospection. This science of the "internal facts of man" would thusbe distinguished from the other natural sciences which are formed bythe use of our outer senses, by external observation--that is to say, to use a neologism, by externospection. This verbal symmetry maysatisfy for a moment minds given to words, but on reflection it isperceived that the distinction between introspection andexternospection does not correspond to a fundamental and constantdifference in the nature of things or in the processes of cognition. Iacknowledge it with some regret, and thus place myself incontradiction with myself; for I for a long time believed, and haveeven said in print, that psychology is the science of introspection. My error arose from my having made too many analyses of detail, andnot having mounted to a sufficiently wide-reaching conception. The definition I have given of consciousness is the impliedcondemnation of the above ideas. Consciousness, being nothing but anact of revelation, has neither a within nor a without; it does notcorrespond to a special domain which would be an inner one with regardto another domain. Every consideration on the position of things is borrowed from thesphere of the object, and remains foreign to the sphere of theconsciousness. It is by an abuse of language that we speak of theouter world in relation to the world of consciousness, and it is pureimagination on the part of philosophers to have supposed that oursensations are first perceived as internal states and states ofconsciousness, and are subsequently projected without to form theouter world. The notion of internal and external is only understoodfor certain objects which we compare by position to certain others. In fact, we find that the opposition between an external and aninternal series is generally founded on two characteristics: sensationis considered external in relation to the idea, and an object ofcognition is considered as internal when it is accessible only toourselves. When these two characteristics are isolated from eachother, one may have doubts; but when they co-exist, then theoutwardness or inwardness appears fully evidenced. We see then thatthis distinction has nothing to do with the value of consciousness, and has nothing mental about it. It is thus that our ideas are judged from internal events. It is ourmicrocosm opposed to the macrocosm. It is the individual opposed tothe social. Looking at an external object, we remain in communion withour fellows, for we receive, or think we receive, identicalsensations. At all events, we receive corresponding sensations. On theother hand, my thought is mine, and is known to me alone; it is mysanctuary, my private closet, where others do not enter. Every one cansee what I see, but no one knows what I think. But this difference in the accessibility of phenomena is not due totheir peculiar nature. It is connected with a different fact, with themodes of excitement which call them forth. If the visual sensation iscommon to all, it is because the exciting cause of the sensation is anobject external to our nervous systems, and acting at a distance onall. [34] The tactile sensation is at the beginning more personal tothe one who experiences it, since it requires contact; and the lowersensations are in this intimacy still in progress. And then, the sameobject can give rise, in common-place circumstances, to a sensationeither common to all beings or special to one alone. The capsule ofantipyrine which I swallow is, before my doing so, visible to alleyes; once in my mouth, I am the only one to perceive it. It istherefore possible that the same sensation, according to thedisplacements of the object which excites it, may make part of theinternal or of the external series; and as all psychic life issensation, even effort, and, as we are assured, emotion, it followsthat our argument extends to all the psychical elements. Finally, the internal or external character of events, which might becalled their geographical position, is a characteristic which has noinfluence upon the method destined to take cognisance of it. Themethod remains one. Introspection does not represent a source ofcognition distinct from externospection, for the same faculties of themind--reason, attention, and reflection--act on sensation, the sourceof the so-called external sciences, and on the idea, the source of theso-called inner science. A fact can be studied by essentially the sameprocess, whether regarded by the eyes or depicted by the memory. Theconsciousness changes its object and orientation, not its nature. Itis as if, with the same opera-glass, we looked in turn at the wall ofthe room and through the window. I can even quote on this point a significant fact: there are observerswho are organised in such a way that they especially observe bymemory. Placed before the sensorial phenomenon which strikes theirsenses, they are sometimes amazed, as if hypnotised; they require toget away from it to regain consciousness of themselves, to analyse thefact, and to master it, and it is by means of the memory that theystudy it, on condition, of course, of afterwards coming back to verifytheir conclusions by a fresh observation from nature. Will it be saidthat the physicist, the chemist, or the biologist who follows thisslow method, and who thus observes retroactively, practises physicsand biology by introspection? Evidently this would be ridiculous. Conversely, introspection may, in certain cases, adopt the procedureof externospection. No doubt it would be inexact to say that theperception of one of our ideas always takes place through the samemechanism as the perception of one of our sensations. To give anaccount of what we think does not imply the same work as in the caseof what we see; for, generally, our thoughts and our images do notappear to us spontaneously. They are first sought for by us, and areonly realised after having been wished for. We go from the vague tothe precise, from the confused to the clear; the direction of thoughtprecedes, then, its realisation in images; and the latter, beingexpected, is necessarily comprehended when it is formed. But we maycome across curious circumstances in which it is the image which hasprecedence over its appearance, and in that case it is exact to saythat this uninvoked image must be interpreted and recognised as if itwere an external object. In cases of this kind, there passes throughour mind something which surprises us. I see, by internal vision, aface with a red nose, and I have to search my memory for a long time, even for days, in order to give precision to the vague feeling that Ihave seen it before, so as to finally say with confidence, "It is Soand So!" Or else I hear in my inner ear a certain voice, with ametallic tone and authoritative inflections: this voice pronouncesscientific phrases, gives a series of lectures, but I know not to whomit belongs, and it costs me a long effort to reach the interpretation:it is the voice of M. Dastre! There is, then, a certain space of time, more or less long, in which we can correctly assert that we are notaware of what we are thinking; we are in the presence of a thought inthe same state of uncertainty as in that of an external, unknown, andnovel object. The labour of classification and of interpretation castupon us is of the same order; and, when this labour is effectedincorrectly, it may end in an illusion. Therefore illusions ofthought are quite as possible as illusions of the senses, though rarerfor the reasons above stated. But the question of frequency has notheoretical importance. I have shown elsewhere, by experiments on hysterics, that it ispossible by the intermediary of their insensibility to touch tosuggest ideas on the value of which the patients make mistakes. Forinstance, you take the finger in which they have no sensation, youtouch it, you bend it. The patient, not seeing what is done, does notfeel it, but the tactile sensation unfelt by their principalconsciousness somehow awakes the visual image of the finger; thisenters into the field of consciousness, and most often is notrecognised by the subject, who describes the occurrence in his ownway; he claims, for instance, that he thinks of sticks or of columns. In reality he does not know of what he is thinking, and we know betterthan he. He is thinking of his finger, and does not recognise it. All these examples show that the clearly defined characteristics intowhich it is sought to divide extrospection and introspection do notexist. There is, however, a reason for preserving the distinction, because it presents a real interest for the psychology of theindividual. These two words introspection and extrospection admirablyconvey the difference in the manner of thinking between those whofrom preference look, and those who from preference reflect. On theone hand, the observers, who are often men of action; on the other, the speculators, who are often mystics. But it would be no morelegitimate by this means to separate psychology and physics than tosay, for instance, "There are two kinds of geology: one is the geologyof France, for one is acquainted with it without going from home, andthe other is that of the rest of the world, because in order to knowit one must cross the frontier. " We reject, therefore, the definition drawn from the difference ofmethod. At bottom there is no difference of method, but onlydifferences of process, of _technique_. The method is always the same, for it is derived from the application of a certain number of laws tothe objects of cognition, and these laws remain the same in allspheres of application. Here is another difference of method which, if it were true, wouldhave an incalculable importance. Psychology, we are told, is a scienceof direct and immediate experiment; it studies facts as they presentthemselves to our consciousness, while the natural sciences aresciences of indirect and mediate experiment, for they are compelled tointerpret the facts of consciousness and draw from them conclusions onnature. It has also been said, in a more ambitious formula, "Thescience of physical objects is relative; logical science is absolute. " Let us examine this by the rapid analysis of any perception taken athaphazard. What I perceive directly, immediately, we are told, is notthe object, it is my state of consciousness; the object is inferred;concluded, and taken cognisance of through the intermediary of mystate of consciousness. We only know it, says Lotze, _circa rem_. Itis therefore apprehended less immediately, and every natural scienceemploys a more roundabout method than that of psychology. This last, by studying states of consciousness, which alone are known to usdirectly, comprehends reality itself, absolute reality. "There is moreabsolute reality, " M. Rabier boldly says, "in the simple feeling thata man, or even an animal, has of its pain when beaten than in all thetheories of physics, for, beyond these theories, it can be asked, whatare the things that exist. But it is an absurdity to ask one's selfif, beyond the pain of which one is conscious, there be not anotherpain different from that one. "[35] Let us excuse in psychologists this petty and common whim forexaggerating the merit of the science they pursue. But here the limitis really passed, and no scholar will admit that the perception andrepresentation of a body, as it may take place in the brain of aBerthelot, can present any inferiority as a cognition of the absolute, to the pain felt by the snail I crush under my foot. Nobody exceptmetaphysicians will acknowledge that psychology is a more precise andcertain science than physics or chemistry. The criterion furnished by the development of the respective scienceswould prove just the contrary. The observations of psychology arealways rather unprecise. Psychological phenomena, notwithstanding theefforts of Fechner and his school, are not yet measured with the samestrictness and ease as the tangible reality. To speak plainly, thepsychologist who vaunts the superiority of his method, and only showsinferior results, places himself in a somewhat ridiculous andcontradictory position; he deserves to be compared to thosespiritualists who claim the power of evoking the souls of theillustrious dead and only get from them platitudes. In the main the arguments of the metaphysicians given above appear tome to contain a grave error. This consists in supposing that thenatural sciences study the reality hidden beneath sensation, and onlymake use of this fact as of a sign which enables them to get back fromeffect to cause. This is quite inexact. That the natural sciences arelimited by sensation is true; but they do not go outside it, theyeffect their constructions with sensation alone. And the reason isvery simple: it is the only thing they know. To the metaphysicalpsychologist, who claims sensation as his own property, saying, "Butthis sensation is a state of my consciousness, it is mine, it ismyself, " the physicist has the right to answer: "I beg your pardon!this sensation is the external object that I am studying; it is mycolumn of mercury, my spring, my precipitate, my amoeba; Icomprehend these objects directly, and I want no other. " Psychologyfinds itself, therefore, exactly on the same footing as the othersciences in the degree in which it studies sensations that itconsiders as its own property. I have already said that the sensationsproper to psychology are hardly represented otherwise than by theemotional sensations produced by the storms in the apparatus oforganic life. We now come to the definitions by content. They have been numerous, but we shall only quote a few. The most usual consists in saying, that_Psychology studies the facts of consciousness_. This formula passes, in general, as satisfactory. The little objection raised against itis, that it excludes the unconscious facts which play so important apart in explaining the totality of mental life; but it only requiressome usual phrase to repair this omission. One might add, forinstance, to the above formula: conscious facts and those which, while unconscious under certain conditions, are yet conscious inothers. This is not, however, the main difficulty, which is far more serious. On close examination, it is seen that the term, _fact ofconsciousness_, is very elastic, and that for a reason easy to state. This is, that all facts which exist and are revealed to us reach us bythe testimony of the consciousness, and are, consequently, facts ofconsciousness. If I look at a locomotive, and analyse its machinery, Iact like a mechanic; if I study under the microscope the structure ofinfusoria, I practise biology; and yet the sight of the locomotive, the perception of the infusoria, are just facts of consciousness, andshould belong to psychology, if one takes literally the abovedefinition, which is so absolute that it absorbs the entire world intothe science of the mind. It might, indeed, be remarked that certainphenomena would remain strictly psychological, such as, for instance, the emotions, the study of which would not be disputed by any physicalscience; for the world of nature offers us nothing comparable to anemotion or an effort of will, while, on the other hand, everythingwhich is the object of physical science--that is, everything which canbe perceived by our external senses--may be claimed by psychology. Therefore, it is very evident the above definition is much too wide, and does not agree with _solo definito_. It does not succeed indisengaging the essential characteristic of physics. Thischaracteristic indeed exists, and we foresee it, but we do notformulate it. Another definition by content has not been much more happy. Toseparate the material from the moral, the conception of Descartes wasremembered, and we were told that: "Psychology is the science of whatexists only in time, while physics is the science of what exists atonce in time and in space. " To this theoretical reasoning it might already be objected that, infact, and in the life we lead, we never cease to localise in space, though somewhat vaguely, our thought, our Ego, and our intellectualwhole. At this moment I am considering myself, and taking myself as anexample. I am writing these lines in my study, and no metaphysicalargument can cause me to abandon my firm conviction that myintellectual whole is in this room, on the second floor of my house atMeudon. I am here, and not elsewhere. My body is here; and my soul, ifI have one, is here. I am where my body is; I believe even that I amwithin my body. This localisation, which certainly has not the exactness nor even thecharacteristics of the localisation of a material body in space, seemsto me to result from the very great importance we attach, to theexistence of our body in perception and in movement. Our bodyaccompanies all our perceptions; its changes of position cause theseperceptions to vary; the accidents which happen to it bring uspleasure or pain. Some of its movements are under our orders; weobserve that others are the consequences of our thoughts and ouremotions. It occupies, therefore, among the objects of cognition aprivileged place, which renders it more intimate and more dear to usthan other objects. There is no need to inquire here whether, inabsolute reality, I am lodged within it, for this "I" is an artificialproduct manufactured from memories. I have before explained what isthe value of the relation subject-object. It is indisputable that inthe manufacture of the subject we bring in the body. This is tooimportant an element for it not to have the right to form part of thesynthesis; it is really its nucleus. As, on the other hand, all theother elements of the synthesis are psychical, invisible, and reducedto being faculties and powers, it may be convenient to consider themas occupying the centre of the body or of the brain. There is no needto discuss this synthesis, for it is one of pure convenience. As wellinquire whether the personality of a public company is reallylocalised at its registered offices, round the green baize coverwhich adorns the table in the boardroom. Another definition of psychology, which is at once a definition bycontent and a definition by method, has often been employed byphilosophers and physiologists. It consists in supposing that therereally exist two ways of arriving at the cognition of objects: thewithin and the without. These two ways are as opposed to each other asthe right and wrong side of a stuff. It is in this sense thatpsychology is the science of the within and looks at the wrong side ofthe stuff, while the natural sciences look at the right side. And itis so true, they add, that the same phenomenon appears under tworadically different forms according as we look at it from the one orthe other point of view. Thus, it is pointed out to us, every one ofour thoughts is in correlation with a particular state of our cerebralmatter; our thought is the subjective and mental face; thecorresponding cerebral process is the objective and material face. Then the difference between representation, which is a purelypsychological phenomenon, and a cerebral state which is a materialone, and reducible to movement, is insisted upon; and it is declaredthat these two orders of phenomena are separated by irreducibledifferences. Lastly, to take account of the meaning of these differences, and toexplain them, it is pointed out that they are probably connected withthe modes of cognition which intervene to comprehend the mental andthe physical. The mental phenomenon, we are told, is comprehended byitself, and as it is; it is known without any mystery, and in itsabsolute reality. The physical phenomenon, on the contrary, onlyreaches us through the intermediary of our nerves, more or lesstransformed in consequence by the handling in transport. It is anindirect cognition which causes us to comprehend matter; we have ofthis last only a relative and apparent notion, which sufficientlyexplains how it may differ from a phenomenon of thought. I have already had occasion to speak of this dualism, when we wereendeavouring to define sensation. We return to its criticism oncemore, for it is a conception which in these days has become classic;and it is only by repeatedly attacking it that it will be possible todemonstrate its error. To take an example: I look at the plain before me, and see a flock ofsheep pass over it. At the same time an observer is by my side and isnot looking at the same thing as myself. It is not at the plain thathe looks; it is, I will suppose, within my brain. Armed with amicroscope _à la_ Jules Verne, he succeeds in seeing what is passingbeneath my skull, and he notices within my fibres and nerve cellsthose phenomena of undulation which physiologists have hithertodescribed hypothetically. This observer notices then, that, while I amlooking over the plain, my optic nerve conveys a certain kind ofmovements--these are, I suppose, displacements of molecules whichexecute a complicated kind of dance. The movement follows the courseof the optic nerve, traverses the chiasma, goes along the fascia, passes the internal capsule, and finally arrives at the visual centresof the occipital region. Here, then, are the two terms of comparisonconstituted: on the one hand, we have a certain representation--thatis, my own; and on the other hand, coinciding with this representationwe have the dynamic changes in the nerve centres. These are the twothings constituting the right and wrong side of the stuff. We shall betold: "See how little similarity there is here! A representation is aphysical fact, a movement of molecules a material fact. " And further, "If these two facts are so little like each other, it is because theyreach us by two different routes. " I think both these affirmations equally disputable. Let us begin withthe second. Where does one see that we possess two different sourcesof knowledge? Or that we can consider an object under two differentaspects? Where are our duplicate organs of the senses, of which theone is turned inward and the other outward? In the example chosen forthis discussion, I have supposed two persons, each of whomexperiences a visual perception. One looks at one object, the other atanother; but both are looking with the same organs of sense, that is, with their eyes. How is it possible to understand that these eyes can, in turn, according to the necessity of the moment, see the two faces, physical and mental, of the same object? They are the two faces of an identical object, is the answer made tous, because the two visions, although applied to the same object, areessentially different. On the one hand is a sensation of displacement, of movement, of a dance executed by the molecules of some proteidsubstance; on the other hand is a flock of sheep passing over theplain at a distance of a hundred metres away. It seems to me that here also the argument advanced is not sound. Inthe first place, it is essential to notice that not only are the twopaths of cognition identical, but also that the perceptions are of thesame nature. There is in this no opposition between the physical andthe mental. What is compared are the two phenomena, which are bothmixed and are physico-mental--physical, through the object to whichthey are applied, mental, through the act of cognition they imply. Toperceive an object in the plain and to perceive a dynamic state of thebrain are two operations which each imply an act of cognition; and, in addition, the object of this knowledge is as material in the one asin the other case. A flock of sheep is matter just as much as mybrain. No doubt, here are objects which differ; my observer and myself havenot the same perception. I acknowledge, but do not wonder at it. Howcould our two perceptions be similar? I look at the sheep, and he atthe interior of my brain. It is not astonishing that, looking at suchdifferent objects, we should receive images also different. Or, again, if this other way of putting it be preferred, I would say: theindividual A looks at the flock through the intermediary of hisnervous system, while B looks at it through that of two nervoussystems, put as it were end to end (though not entirely), his ownnervous system first, and then that of A. How, then, could theyexperience the same sensation? They could only have an identical sensation if the idea of theancients were to be upheld, who understood the external perception ofbodies to result from particles detaching themselves from theirbodies, and after a more or less lengthy flight, striking and enteringinto our organs of sense. [36] Let us imagine, just for a moment, one of our nerves--the opticnerve, for instance--transformed into a hollow tube, along which theemissions of miniatures should wend their way. In this case, evidently, if so strange a disposition were to be realised, and if Bcould see what was flowing in the optic nerve of A, he wouldexperience a sensation almost analogous to that of A. Whenever thelatter saw a dog, a sheep, or a shepherd, B would likewise see in theoptic canal minute dogs, microscopic sheep, and Lilliputian shepherds. At the cost of such a childish conception, a parity of content in thesensations of our two spectators A and B might be supposed. But I willnot dwell on this. The above considerations seem to me to explain the differencegenerally noticed between thought and the physiological process. It isnot a difference of nature, an opposition of two essences, or of twoworlds--it is simply a difference of object; just that which separatesmy visual perception of a tree and my visual perception of a dog. There remains to know in what manner we understand the relation ofthese two processes: this is another problem which we will examinelater. Since the content does not give us the differentiation we desire, wewill abandon the definitions of psychology by content. What nowremains? The definitions from the point of view. The same fact may helooked at, like a landscape, from different points of view, andappears different with the changes therein. It is so with the facts weconsider psychical, and the autonomy of psychology would thus be amatter of point of view. It has, then, been supposed--and this is a very importantproposition--that the distinctive feature of psychical facts does notconsist in their forming a class of particular events. On thecontrary, their characteristic is to be studied in their dependency onthe persons who bring them about. This interesting affirmation is notnew: it may be read in the works of Mach, Külpe, Münsterberg, and, especially, of Ebbinghaus, from whom I quote the following lines ofquite remarkable clearness: "Psychology is not distinguished fromsciences like physics and biology, which are generally and rightlyopposed to it, by a different content, in the way that, for instance, zoology is distinguished from mineralogy or astronomy. It has the samecontent, but considers it from a different point of view and with adifferent object. It is the science, not of a given part of the world, but of the whole world, considered, however, in a certain relation. Itstudies, in the world, those formations, processes, and relations, theproperties of which are essentially determined by the properties andfunctions of an organism, of an organised individual. .. . Psychology, in short, considers the world from an individual and subjective pointof view, while the science of physics studies it as if it wereindependent of us. " Over these definitions by point of view, one might quibble a little;for those who thus define psychology are not always consistent withthemselves. In other passages of their writings they do not fail tooppose psychical to physiological phenomena, and they proclaim theirreducible heterogeneity of these two orders of phenomena and theimpossibility of seeing in physics the producing cause of the moral. Ebbinghaus is certainly one of the modern writers who have moststrongly insisted on this idea of opposition between the physiologicaland the psychical, and he is a convinced dualist. Now I do not veryclearly understand in what the principle of heterogeneity can consistto a mind which admits, on the other hand, that psychology does notdiffer from the physical sciences by its content. However, I confine myself here to criticising the consequences and notthe starting point. The definition of the psychical phenomenon by thepoint of view seems to me correct, although it has more concision thanclearness; for it rests especially upon a material metaphor, and theexpression "point of view" hardly applies except to the changes ofperspective furnished by visible objects. It would be more exact to say that psychology specially studiescertain objects of cognition, such as those which have the characterof representations (reminiscences, ideas, concepts), the emotions, thevolitions, and the reciprocal influences of these objects amongthemselves. It studies, then, a part of the material world, of thatworld which till now has been called psychological, because it doesnot come under the senses, and because it is subjective andinaccessible to others than ourselves; it studies the laws of thoseobjects, which laws have been termed mental. [37] These laws are not recognised, popularly speaking, either in physicsor in biology; they constitute for us a cognition apart from that ofthe natural world. Association by resemblance, for example, is a lawof consciousness; it is a psychological law which has no applicationnor counterpart in the world of physics or biology. We may thereforesum up what has been said by the statement that psychology is thestudy of a certain number of laws, relations, and connections. As to the particular feature which distinguishes mental from physicallaws, we can formulate it, as does William James, by saying that theessence of a mental law is to be teleological, or, if the phrase bepreferred, we can say that mental activity is a finalistic activity, which expends itself as will in the pursuit of future ends, and asintelligence in the choice of the means deemed capable of servingthose ends. An act of intelligence is recognised by the fact of itsaiming at an end, and employing for this end one means chosen out ofmany. Finality and intelligence are thus synonymous. In opposition tomental law, physical law is mechanical, by which expression is simplyimplied the absence of finality. Finality opposed to mechanism; suchis the most concise and truest expression in which must be sought thedistinctive attribute of psychology and of the moral sciences, theessential characteristic by which psychological are separated fromphysical facts. I think it may be useful to dwell a little on the mental laws which Ihave just opposed to the physical, and whose object is to assurepreadaptation and form a finality. [38] Their importance cannot beexaggerated. Thanks to his power of preadaptation, the being endowedwith intelligence acquires an enormous advantage over everything whichdoes not reason. No doubt, as has been shrewdly remarked, naturalselection resembles a finality, for it ends in an adaptation of beingsto their surroundings. There is therefore, strictly speaking, such athing as finality without intelligence. But the adaptation resultingtherefrom is a crude one, and proceeds by the elimination of all thatdoes not succeed in adapting itself; it is a butchery. Real finalismsaves many deaths, many sufferings, and many abortions. [39] Let us examine, then, the process of preadaptation; it will enable usto thoroughly comprehend, not only the difference between the physicaland the psychical laws, but the reason why the psychical manages insome fashion to mould itself upon the physical law. Now, the means employed by preadaptation is, if we take the matter inits simplest form, to be aware of sensations before they areexperienced. If we reflect that all prevision implies a previousknowledge of the probable trend of events, it will be understood thatthe part played by intelligence consists in becoming imbued with thelaws of nature, for the purpose of imitating its workings. By thelaws of nature, we understand here only that order of real sensations, the knowledge of which is sufficient to fulfil the wants of practicallife. To us there are always gaps in this order, because the sensationit is important for us to know is separated from us either by thebarriers of time or of space, or by the complication of uselesssensations. Thence the necessity of interpolations. That which we donot perceive directly by our senses, we are obliged to represent toourselves by our intelligence; the image does the work of sensation, and supplements the halting sensation in everything which concernsadaptation. To replace the inaccessible sensation by the corresponding image, istherefore to create in ourselves a representation of the outer worldwhich is, on all the points most useful to us, more complete than thedirect and sensorial presentation of the moment. There is in us apower of creation, and this power exercises itself in the imitation ofthe work of nature; it imitates its order, it reconstitutes on thesmall scale adapted to our minds, the great external order of events. Now, this work of imitation is only really possible if the imitatorhas some means at his disposal analogous to those of the model. Our minds could not divine the designs of nature, if the laws ofimages had nothing in common with the laws of nature. We are thus ledto confront these two orders of laws with each other; but, beforedoing so, one more preliminary word is necessary. We have up till nowsomewhat limited the problem, in order to understand it. We havereduced the psychological being to one single function, theintellectual, and to one single object of research, the truth. Thisis, however, an error which has often been committed, which is nowknown and catalogued, called intellectualism, or the abuse ofintellectualism. It is committed for this very simple reason, that itis the intellectual part of our being which best allows itself to beunderstood, and, so to speak, intellectualised. But this leaves out ofthe question a part of our entire mental being so important and soeminent, that if this part be suppressed, the intelligence would ceaseto work and would have no more utility than a machine without motivepower. Our own motive power is the will, the feeling, or the tendency. Will is perhaps the most characteristic psychical function, since, asI have already had occasion to say, nothing analogous to it is metwith in the world of nature. Let us therefore not separate the willfrom the intelligence, let us incarnate them one in the other; and, instead of representing the function of the mind as having for its aimknowledge, foresight, the combination of means, and self-adaptation, we shall be much nearer the truth in representing to ourselves abeing who _wills_ to know, _wills_ to foresee, and _wills_ to adapthimself, for, after all, he _wills_ to live. Having said this, let us compare the psychological law and that ofnature. Are they identical? We shall be told that they are not, since, as a fact, errors are committed at every moment by the sudden failuresof human reason. This is the first idea which arises. Human error, itwould seem, is the best proof that the two laws in question are notalike, and we will readily add that a falling stone does not mistakeits way, that the crystal, in the course of formation does not misstaking the crystalline shape, because they form part of physicalnature, and are subject in consequence to its determinism. But this isfaulty reasoning, and a moment of reflection demonstrates it in theclearest possible manner; for adaptation may miss its aim without thebeing who adapts himself and his surroundings necessarily obeyingdifferent laws. When the heat of a too early spring causes buds toburst forth prematurely which are afterwards destroyed by frost, thereis produced a fault of adjustment which resembles an error ofadaptation, and the bringing forward of this error does notnecessarily imply that the tree and the whole of physical nature areobeying different laws. Moreover, the difference between the laws ofnature and those of the understanding does not need deduction byreasoning from an abstract principle; it is better to say that it isdirectly observable, and this is how I find that it presents itself tous. The essential law of nature is relatively easy to formulate, as it iscomprised in the very definition of law. It simply consists in thesentence: uniformity under similar conditions. We might also say: aconstant relation between two or several phenomena, which can also beexpressed in a more abstract way by declaring that the law of naturerests on the combination of two notions, identity and constancy. On the other hand, the laws of our psychical activity partlycorrespond to the same tendencies, and it would be easy to demonstratethat the microcosm of our thoughts is governed by laws which are alsoan expression of these two combined notions of constancy and identity. It is, above all, in the working of the intellectual machine, the bestknown and the most clearly analysed up till now, that we see theapplication of this mental law which resembles, as we say, on certainsides, the physical law: and the best we can do for our demonstrationwill doubtless be to dissect our reasoning powers. Reason, a processessential to thought in action, is developed in accordance with a lawwhich resembles in the most curious manner a physical law. Itresembles it enough to imitate it, to conform to it, and, so to speak, to mould itself on it. Now, the reason does not follow the caprices of thought, it is subjectto rules; it results from the properties of the images, thoseproperties which we have above referred to, the material character ofwhich we have recognised, and which are two in number--similarity andcontiguity, as they are termed in the jargon of the schools. They areproperties which have for their aim to bring things together, tounite, and to synthetise. They are unceasingly at work, and soapparent in their labour that they have long been known. We know, since the time of Aristotle, that two facts perceived at the same timereproduce themselves together in the memory--this is the law ofcontiguity; and that two facts perceived separately, but which aresimilar, are brought together in our mind--this is the law ofsimilarity. Now, similarity and contiguity form by combination the essential partof all kinds of reasoning, and this reasoning, thus understood, worksin a fashion which much resembles (we shall see exactly in whatdegree) a physical law. I wish to show this in a few words. Whatrenders my demonstration difficult and perhaps obscure is, that weshall be obliged to bring together rather unexpectedly categories ofphenomena which are generally considered separate. The distinctive attribute of the reason consists, as I have said, inthe setting to work of these two elementary properties, similarity andcontiguity. It consists, in fact, in extending continuity bysimilarity; in endowing with identical properties and similaraccompaniments things which resemble each other; in other words, itconsists in impliedly asserting that the moment two things areidentical in one point they are so for all the rest. This will befairly well understood by imagining what takes place when mentalimages having the above-mentioned properties meet. Suppose that B isassociated with C, and that A resembles B. In consequence of theirresemblance the passing from A to B is easy; and then B suggesting Cby contiguity, it happens that this C is connected with A connected, though, in reality, they have never been tried together. I say theyare associated on the basis of their relation to B, which is therallying point. It is thus that, on seeing a piece of red-hot iron(A), I conclude it is hot (C), because I recollect distinctly orunconsciously another piece of red-hot iron (B), of which I onceexperienced the heat. It is this recollection B which logicians, intheir analysis of logical, verbal, and formal argument, call themiddle term. Our representation of the process of reasoning is notspecial to argument. It also expresses the process of invention, andevery kind of progress from the known to the unknown. It is anactivity which creates relations, which assembles and binds together, and the connections made between different representations are due totheir partial identities, which act as solder to two pieces of metal. It will now be understood that these relations between the imagescuriously resemble the external order of things, the order of oursensations, the order of nature, the physical law. This is becausethis physical law also has the same character and expresses itselfsimilarly. We might say "all things which resemble each other have thesame properties, " or "all things alike on one point resemble eachother on all other points. " But immediately we do so, the differencebetween the physical and the mental law becomes apparent. The formulawe have given is only true on condition that many restrictions anddistinctions are made. The process of nature is so to do that the _same_ phenomenon alwaysunfolds itself in the same order. But this process is not alwayscomprehended in real life, for it is hidden from our eyes by themanifold combinations of chance; in the reality that we perceive thereis a crowd of phenomena which resemble each other but are not reallythe same. There are a number of phenomena which co-exist or followeach other without this order of co-existence or succession beingnecessary or constant. In other words, there are resemblances whichare the marks of something, as a logician would say, and others whichare not the marks of anything; there are relations of time and spacewhich are the expression of a law; there are some which areaccidental, and may possibly never be reproduced. It would be a wonderful advantage if every scientific specialist wouldmake out a list of the non-significant properties that he recognisesin matter. The chemist, for example, would show us that specificweight has hardly any value in diagnosis, that the crystalline form ofa salt is often not its own, that its colour especially is almostnegligible because an immense number of crystals are white orcolourless, that precipitation by a given substance does notordinarily suffice to characterise a body, and so on. The botanist, onhis part, would show us that, in determining plants, absolutedimension is less important than proportion, colour less importantthan form, certain structures of organs less important than others. The pathologist would teach us that most pathological symptoms havebut a trivial value; the cries, the enervation, the agitation of apatient, even the delirium which so affects the bystanders, are lesscharacteristic of fever than the rate of his pulse, and the latterless than the temperature of the armpit or the dryness of the tongue, &c. At every moment the study of science reveals resemblances of factsand contiguities of facts which must be neglected for the sake ofothers. And if we pass from this profound knowledge of the objects tothe empirical knowledge, to the external perception of bodies, it isin immense number that one espies around one traps laid by nature. Thesound we hear resembles several others, all produced by differentcauses; many of our visual sensations likewise lend themselves to themost varied interpretations; by the side of the efficient cause of anevent we find a thousand entangled contingencies which appear soimportant that to disentangle them we are as much perplexed as thesavage, who, unable to discriminate between causes and coincidences, returns to drink at the well which has cured him, carefully keeping tothe same hour, the same gestures, and the same finery. The reason of this is that the faculty of similarity and the facultyof contiguity do not give the distinction, necessary as it is, betweenresemblances and co-existences which are significant and those whichare not. The causal nexus between two phenomena is not perceived assomething apart and _sui generis_; it is not even perceived at all. Weperceive only their relation in time and space, and it is our mindwhich raises a succession to the height of a causal connection, byintercalating between cause and effect something of what we ourselvesfeel when we voluntarily order the execution of a movement. This isnot the place to inquire what are the experimental conditions in whichwe subject phenomena to this anthropomorphic transformation; it willsuffice for us to repeat here that, in perception, a chance relationbetween phenomena impresses us in the same way as when it is theexpression of a law. Our intellectual machine sometimes works in accord with the externallaw and at others makes mistakes and goes the wrong way. Then we areobliged to correct it, and to try a better adjustment, either byprofounder experimenting with nature (methods of concordance, discordance, variations, &c. ), or by a comparison of differentjudgments and arguments made into a synthesis; and this collaborationof several concordant activities ends in a conclusion which can neverrepresent the truth, but only the probable truth. The study of thelaws of the mind shows us too clearly, in fact, their fluidity withregard to the laws of nature for us not to accept probabilism. Thereexists no certitude--only very varied degrees of probability. Dailypractice contents itself with a very low degree of probability;judicial logic demands a rather higher one, especially when it is aquestion of depriving one of our fellow-creatures of liberty or life. Science claims one higher still. But there is never anything butdifferences of degrees in probability and conjecture. This, then, is the definition of psychology that we propose. Itstudies a certain number of laws which we term mental, in oppositionto those of external nature, from which they differ, but which, properly speaking, do not deserve the qualification of mental, sincethey are--or at least the best known of them are--laws of the images, and the images are material elements. Although it may seem absolutelyparadoxical, psychology is a science of matter--the science of a partof matter which has the property of preadaptation. FOOTNOTES: [Footnote 33: LANGE, _Histoire du Matérialisme_, II. , 2me. Partie, chap. Iii. ] [Footnote 34: Let us remark, in passing, how badly nature hasorganised the system of communication between thinking beings. In whatwe experience we have nothing in common with our fellows; each oneexperiences his own sensations and not those of others. The onlymeeting point of different minds is found in the inaccessible domainof the _noumena. _] [Footnote 35: E. RABIER, _Leçons de Philosophie_, "Psychologie, " p. 33. ] [Footnote 36: This seems to have been the opinion of Democritus. Themodern doctrine of radiation from the human body, if established, would go nearly as far as the supposition in the text. Up till now, however, it lacks confirmation. --ED. ] [Footnote 37: I am compelled, much against my will, to use throughoutthis passage an equivocal expression, that of "mental law, " or law ofconsciousness, or psychological law. I indicate by this the laws ofcontiguity and of similarity; as they result from the properties ofthe images, and as these are of a material nature, they are reallyphysical and material laws like those of external nature. But how canall these laws be called physical laws without running the risk ofconfusing them one with the other?] [Footnote 38: _Finality_ seems to be here used in the sense of thedoctrine which regards perfection as the final cause ofexistence. --ED. ] [Footnote 39: See a very interesting article by E. GOBLOT, "LaFinalité sans Intelligence, " _Revue de Métaphysique_, July 1900. ] BOOK III THE UNION OF THE SOUL[40] AND THE BODY CHAPTER I THE MIND HAS AN INCOMPLETE LIFE The problem of the union of the mind and the body is not one of thosewhich present themselves in pure speculation; it has its roots inexperimental facts, and is forced upon us by the necessity ofexplaining observations such as those we are about to quote. The force of our consciousness, the correctness of our judgments, ourtempers and our characters, the state of health of our minds, and alsotheir troubles, their weaknesses, and even their existence, are all ina state of strict dependence on the condition of our bodies, moreprecisely with that of our nervous systems, or, more precisely still, with the state of those three pounds of proteid substance which eachof us has at the back of his forehead, and which are called ourbrains. This is daily demonstrated by thousands upon thousands ofobservations. The question is to know how this union of the body with theconsciousness is to be explained, it being assumed that the two termsof this union present a great difference in their nature. The easierit seems to demonstrate that this union exists, the more difficult itappears to explain how it is realised; and the proof of thisdifficulty is the number of divergent interpretations given to it. Were it a simple question of fact, the perpetual discussions andcontroversies upon it would not arise. Many problems here present themselves. The first is that of thegenesis or origin of the consciousness. It has to be explained how apsychical phenomenon can appear in the midst of material ones. Ingeneral, one begins by supposing that the material phenomena areproduced first; they consist, for instance, in the working of thenervous centres. All this is physical or chemical, and thereforematerial. Then at a given moment, after this mechanical process, aquite different phenomenon emerges. This is thought, consciousness, emotion. Then comes the question whether this production of thought inthe midst of physical phenomena is capable of explanation, and howthought is connected with its physical antecedents. What is the natureof the link between them? Is it a relation of cause to effect, ofgenesis? or a coincidence? or the interaction of two distinct forces?Is this relation constant or necessary? Can the mind enjoy anexistence independent of the brain? Can it survive the death of thebrain? The second question is that of knowing what is the rôle, the utility, and the efficacity of the psychical phenomenon. Once formed, thisphenomenon evolves in a certain direction and assumes to us who haveconsciousness of it a very great importance. What is its action on thematerial phenomena of the brain which surround it? Does it developaccording to laws of its own, which have no relation to the laws ofbrain action? Does it exercise any action on these intra-cerebralfunctions? Does it exercise any action on the centrifugal currentswhich go to the motor nerves? Is it capable of exciting a movement? oris it deprived of all power of creating effect? We will briefly examine the principal solutions which the imaginationof mankind has found for these very difficult problems. Some of thebest known of these solutions bear the names of spiritualism, materialism, parallelism, and monism. We will speak of these and ofsome others also. Before beginning our critical statement, let us recall some of theresults of our previous analyses which here intrude themselves, to usethe ambitious language of Kant, as the prolegomena to every futuresolution which claims the title of science. In fact, we are now nolonger at the outset of our investigation. We have had to acknowledgethe exactness of certain facts, and we are bound to admit theirconsequences. Notably, the definition of psychical phenomena at whichwe arrived, not without some trouble, will henceforth play a ratherlarge part in our discussion. It will force us to question a greatmetaphysical principle which, up till now, has been almost universallyconsidered as governing the problem of the union of the mind with thebody. This principle bears the name of the _axiom of heterogeneity_, or theprinciple of _psycho-physical dualism_. No philosopher has moreclearly formulated it, and more logically deduced its consequences, than Flournoy. This author has written a little pamphlet called_Métaphysique et Psychologie_, wherein he briefly sets forth all theknown systems of metaphysics by reducing them to the so-calledprinciple of heterogeneity; after this, the same principle enables himto "execute" them. He formulates it in the following terms: "body andmind, consciousness and the molecular cerebral movement of the brain, the psychical fact and the physical fact, although simultaneous, areheterogeneous, unconnected, irreducible, and obstinately two. "[41] Thesame author adds: "this is evident of itself, and axiomatic. Everyphysical, chemical, or physiological event, in the last resort, simplyconsists, according to science, in a more or less rapid displacementof a certain number of material elements, in a change of their mutualdistances or of their modes of grouping. Now, what can there be incommon, I ask you, what analogy can you see, between this drawingtogether or moving apart of material masses in space, and the fact ofhaving a feeling of joy, the recollection of an absent friend, theperception of a gas jet, a desire, or of an act of volition of anykind?" And further on: "All that we can say to connect two events soabsolutely dissimilar is, that they take place _at the same time_. .. . This does not mean that we wish to reduce them to unity, or to jointhem together by the link of causality . .. It is impossible toconceive any real connection, any internal relation between these twounconnected things. " Let us not hesitate to denounce as false this proposition which ispresented to us as an axiom. On looking closely into it, we shallperceive that the principle of heterogeneity does not contain theconsequences it is sought to ascribe to it. It seems to me it shouldbe split up into two propositions of very unequal value: 1, the mindand body are heterogeneous; 2, by virtue of this heterogeneity it isnot possible to understand any direct relation between the two. Now, if the first proposition is absolutely correct, in the sense thatconsciousness and matter are heterogeneous, the second propositionseems to us directly contrary to the facts, which show us that thephenomena of consciousness are incomplete phenomena. The consciousnessis not sufficient for itself; as we have said, it cannot exist byitself. This again, if you like, is an axiom, or rather it is a factshown by observation and confirmed by reflection. Mind and matterbrought down to the essential, to the consciousness and its object, form a natural whole, and the difficulty does not consist in unitingbut in separating them. Consider the following fact: "I experience asensation, and I have consciousness of it. " This is the coupling oftwo things--a sensation and a cognition. The two elements, if we insist upon it, are heterogeneous, and theydiffer qualitatively; but notwithstanding the existing prejudice byreason of which no direct relation, no commerce, can be admittedbetween heterogeneous facts, the alliance of the consciousness and thesensation is the natural and primitive fact. They can only beseparated by analysis, and a scrupulous mind might even ask whetherone has the right to separate them. I have a sensation, and I haveconsciousness of it. If not two facts, they are one and the same. Now, sensation is matter and my consciousness is mind. If I am judging anassortment of stuffs, this assortment, or the sensation I have ofthem, is a particle of matter, a material state, and my judgment onthis sensation is the psychical phenomenon. We can neither believe, nor desire, nor do any act of our intelligence without realising thiswelding together of mind and matter. They are as inseparable as motionand the object that moves; and this comparison, though far-fetched, isreally very convenient. Motion cannot exist without a mobile object;and an object, on the other hand, can exist without movement. In thesame way, sensation may exist without the consciousness; but theconverse proposition, consciousness without sensation, without anobject, an empty consciousness or a "pure thought, " cannot beunderstood. Let us mark clearly how this union is put forward by us. We describeit after nature. It is observation which reveals to us the union andthe fusion of the two terms into one. Or, rather, we do not evenperceive their union until the moment when, by a process of analysis, we succeed in convincing ourselves that that which we at firstconsidered single is really double, or, if you like, can be made intotwo by the reason, without being so in reality. Thus it happens thatwe bring this big problem in metaphysics on to the field ofobservation. Our solution vaguely resembles that which has sometimes been presentedunder the ancient name of _physical influx_, or under the more modernname of _inter-actionism_. There are many authors who maintain thatthe soul can act directly on the body and modify it, and this is whatis called inter-actionism. Thereby is understood, if I mistake not, anaction from cause to effect, produced between two terms which enjoy acertain independence with regard to each other. This interpretation isindubitably close to ours, though not to be confused with it. Mypersonal interpretation sets aside the idea of all independence of themind, since it attributes to the mind an incomplete and, as it were, avirtual existence. If we had to seek paternity for ideas I would much rather turn toAristotle. It was not without some surprise that I was able toconvince myself that the above theory of the relations between thesoul and the body is to be found almost in its entirety in the greatphilosopher. It is true that it is mixed up with many accessory ideaswhich are out of date and which we now reject; but the essential ofthe theory is there very clearly formulated, and that is the importantpoint. A few details on this subject will not be out of place. I givethem, not from the original source, which I am not erudite enough toconsult direct, but from the learned treatise which Bain has publishedon the psychology of Aristotle, as an appendix to his work on theSenses and the Intelligence. The whole metaphysics of Aristotle is dominated by the distinctionbetween form and matter. This distinction is borrowed from the mostfamiliar fact in the sensible world--the form of solid objects. We mayname a substance without troubling ourselves as to the form itpossesses, and we may name the form without regard to the substancethat it clothes. But this distinction is a purely abstract one, forthere can be no real separation of form from matter, no form withoutmatter, and no matter without form. The two terms are correlative;each one implies the other, and neither can be realised or actualisedwithout the other. Every individual substance can be considered from atriple point of view: 1st, form; 2nd, matter; and 3rd, the compound oraggregate of form and matter, the inseparable _Ens_, which transportsus out of the domain of logic and abstraction into that of reality. Aristotle recognises between these two logical correlatives adifference in rank. Form is superior, nobler, the higher in dignity, nearer to the perfect entity; matter is inferior, more modest, moredistant from perfection. On account of its hierarchical inferiority, matter is often presented as the second, or _correlatum_, and form asthe first, or _relatum_. This difference in rank is so stronglymarked, that these two correlations are likewise conceived in adifferent form--that of the potential and the actual. Matter is thepotential, imperfect, roughly outlined element which is not yetactual, and may perhaps never become so. Form is the actual, theenergy, the entelechy which actualises the potential and determinesthe final compound. These few definitions will make clear the singularly ingenious idea ofAristotle on the nature of the body, the soul, and of their union. Thebody is matter which is only intelligible as the _correlatum_ of form;it can neither exist by itself nor be known by itself--that is to say, when considered outside this relation. The soul is form, the actual. By uniting with the body it constitutes the living subject. The soulis the _relatum_, and is unintelligible and void of sense without its_correlatum_. "The soul, " says Aristotle, "is not a variety of body, but it could not exist without a body: the soul is not a body, butsomething which belongs or is relative to a body. " The animatedsubject is a form plunged and engaged in matter, and all its actionsand passions are so likewise. Each has its formal side which concernsthe soul, and its material side which concerns the body. The emotionwhich belongs to the animated subject or aggregate of soul and body isa complex fact having two aspects logically distinguishable from eachother, each of which is correlative to the other and implies it. It isthus not only with our passions, but also with our perceptions, ourimaginations, reminiscences, reasonings, and efforts of attention tolearn. Intelligence, like emotion, is a phenomenon not simply of thecorporeal organism nor of the [Greek: Nous] only, but of thecommonalty or association of which they are members, and when theintelligence weakens it is not because the [Greek: Nous] is altered, but because the association is destroyed by the ruin of the corporealorganism. These few notes, which I have taken in their integrity from Bain'stext, allow us thoroughly to comprehend the thought of Aristotle, andit seems to me that the Greek philosopher, by making of the soul andbody two correlative terms, has formed a comparison of greatexactness. I also much admire his idea according to which it isthrough the union of the body and soul that the whole, which till thenwas only possible, goes forth from the domain of logic and becomesactual. The soul actualises the body, and becomes, as he said, itsentelechy. These views are too close to those I have myself just set forth for itto be necessary to dwell on their resemblance. The latter would becomestill stronger if we separated from the thought of Aristotle a fewdevelopments which are not essential, though he allowed them greatimportance: I refer to the continual comparison he makes with the formand matter of corporeal objects. Happy though it may be, thiscomparison is but a metaphor which perhaps facilitates theunderstanding of Aristotle's idea, but is not essential to his theory. For my part, I attach far greater importance to the character of_relatum_, and _correlatum_ ascribed to the two terms mind and matter, and to the actualisation[42] produced by their union. Let me add another point of comparison. Aristotle's theory recalls ina striking manner that of Kant on the _a priori_ forms of thought. Theform of thought, or the category, is nothing without the matter ofcognition, and the latter is nothing without the application of form. "Thoughts without content given by sensation are empty; intuitionswithout concept furnished by the understanding are blind. " There isnothing astonishing in finding here the same illustration, since thereis throughout a question of describing the same phenomenon, --therelation of mind to matter. There remains to us to review the principal types of metaphysicalsystems. We shall discuss these by taking as our guide the principlewe have just evolved, and which may be thus formulated: _The phenomenaof consciousness constitute an incomplete mode of existence. _ FOOTNOTES: [Footnote 40: See [Note 1] on p. 3. ] [Footnote 41: For reference, see [Note 18] on p. 73. --ED. ] [Footnote 42: _i. E. _ rendering actual. --ED. ] CHAPTER II SPIRITUALISM[43] AND IDEALISM Flournoy has somewhere written that the chief interest of the systemsof metaphysics lies less in the intellectual constructions they raisethan in the aspirations of the mind and of the heart to which theycorrespond. Without taking literally this terribly sceptical opinion, it would be highly useful to begin the study of any metaphysicalsystem by the psychology of its author. The value of each system wouldbe better understood, and their reasons would be comprehended. This book is too short to permit us to enter into such biographicaldetails. I am obliged to take the metaphysical systems _en bloc_, asif they were anonymous works, and to efface all the shades, occasionally so curious, that the thought of each author hasintroduced into them. Yet, however brief our statement, it seemsindispensable to indicate clearly the physical or moral ideaconcealed within each system. SPIRITUALISM It is known that spiritualism is a doctrine which has for its chiefaim the raising of the dignity of man, by recognising in him facultiessuperior to the properties of matter. We constantly meet, inspiritualism, with the notion of superior and inferior, understood notonly in an intellectual sense but also in the sense of moral worth. It will also be remarked, as a consequence of the above principle, that a spiritualist does not confine himself to discussing the ideasof his habitual adversary, the materialist; he finds them not onlyfalse, but dangerous, and is indignant with them; some persons eveningenuously acknowledge that they hold firmly to certain principlesbecause they fear to be converted to materialism. I can also discernin this system a very natural horror of death, which inspires in somany people, of whom I am one, both hatred and disgust. Thespiritualist revolts against the prospect of a definitive annihilationof thought, and the system he adopts is largely explained as an efforttowards immortality. This effort has led to the theory of two substances, the soul and thebody, which are represented as being as thoroughly separated aspossible. The soul has not its origin in the body, and it derives noneof its properties from its fellow; it is a substance created incomplete independence relatively to the body; the soul, in itsessence, has nothing in common with matter. The essence of the soul, said Descartes, is thought; the essence of the body is extent. Itfollows from this that the soul, in its determinations and actions, isliberated from the laws and necessities of the corporeal nature; it isa free power, a power of indetermination, capable of choice, capableof introducing new, unforeseen, and unforeseeable actions, and on thispoint opposes itself to corporeal phenomena, which are all subject toa determinism so rigorous that any event could be foreseen if itsantecedents were known. Another consequence of spiritualism is theadmission of the immortality of the soul, which, being widely distinctfrom the body, is not affected by its dissolution; it is, on thecontrary, liberated, since death cuts the link which binds themtogether. But there is a link, and the explanation of this link brings with itthe ruin of the whole system. One is forced to admit that thisprinciple of the separation of body and soul is liable, in fact, tomany exceptions. Even if they are two isolated powers, the necessitiesof life oblige them to enter continually into communication with eachother. In the case of perceptions, it is the body which acts on thesoul and imparts sensations to it; in movements, it is the soul, onthe contrary, which acts on the body, to make it execute its desiresand its will. Spiritualists must acknowledge that they are at some trouble toexplain this traffic between the two substances; for, with theirrespect for the principle of heterogeneity mentioned above, they donot manage to conceive how that contact of the physical and the mentalcan be made which is constantly necessary in the life of relation. Bywhat means, have they long asked themselves, can that which is onlyextent act on that which is only thought? How can we represent toourselves this _local_ union of matter with an immaterial principle, which, by its essence, does not exist in space? The two substanceshave been so completely separated, to insure the liberty of the souland its superiority over the body, that it has become impossible tobring them together. The scission has been too complete. They cannotbe sewn together again. Such are the principal objections raised against spiritualism. Theseobjections are derived from points of view which are not ours, and wehave therefore no need to estimate their value. From our point of view, the spiritualist conception has chosen anexcellent starting point. By establishing the consciousness and theobject of cognition as two autonomous powers, neither of which is theslave of the other, spiritualism has arrived at an opinion ofirreproachable exactness; it is indeed thus that the relations ofthese two terms must be stated; each has the same importance and theright to the same autonomy. [44] Yet, spiritualism has not rested there, and, by a lamentableexaggeration, it has thought that the consciousness, which it callsthe soul, could exercise its functions in complete independence of theobject of cognition, which it calls matter. There is the error. Itconsists in misunderstanding the incomplete and, as it were, virtualexistence of the consciousness. This refutation is enough as regardsspiritualism. Nothing more need be added. IDEALISM Idealism is an exceedingly complex system, varying much with varyingauthors, very polymorphous, and consequently very difficult todiscuss. The ancient hylozoism, the monadism of Leibnitz, and the recentpanpsychism of M. Strong are only different forms of the samedoctrine. Like spiritualism, with which it is connected by many ties, idealismis a philosophy which expresses some disdain for matter, but thethoughts which have sought to shelter themselves under this philosophyare so varied that it would be perilous to try to define them briefly. There can be discussed in idealism a certain number of affirmationswhich form the basis of the system. None of these affirmations is, strictly speaking, demonstrated or demonstrable; but they offer verydifferent degrees of probability, and it is for this reason that weshall notice them. Amongst these affirmations there are some that we have already metwith in our study of the definition of sensation; others will be newerto us. 1. Here is one which seems to arise directly from the facts, andappears for a long time to have constituted an impregnable positionfor idealists. It may be expressed in three words: _esse est percipi_. Starting with the observation that every time we bear witness to theexistence of the external world, it is because we perceive it, idealists admit that the existence of this external world sharesexactly the lot of our perception, and that like it it isdiscontinuous and intermittent. When we close our eyes, it ceases toexist, like a torch which is extinguished, and lights up again when weopen them. We have already discussed this proposition, and have shownthat it contains nothing imperative; and we may very well decline tosubscribe to it. 2. There follows a second proposition, barely distinct from theprevious one. There should be nothing else in objects but that whichwe perceive, and that of which we have consciousness should be, in thefullest possible acceptation of the words, the measure of what is. Consequently there should be no need to seek, under the objectperceived, another and larger reality, a source from which might flowwider knowledge than that we at present possess. This is as disputableas the preceding affirmation, and for the same reasons. 3. The third proposition is the heart of the idealist thesis. It issometimes presented as a deduction from the foregoing, but it isnevertheless thoroughly distinct from it, and the precedingaffirmations might legitimately be accepted and this new one rejected. This proposition may be expressed thus: _Everything that is perceivedis psychical. _ It is not only idealists who subscribe to this opinion, however, andwe have seen, when dealing with the definition of matter, that it iswidely spread. We understand by it that the objects we perceive existin the consciousness, are of the consciousness, and are constitutedby ideas; the whole world is nothing but idea and representation; and, since our mind is taken to be of a psychical nature, the result isthat everything, absolutely everything, the person who knows and thething known, are all psychical. This is panpsychism. Flournoy, on thispoint, says, with a charm coloured by irony: "We henceforth experiencea sweet family feeling, we find ourselves, so to speak, _at home_ inthe midst of this universe . .. "[45] We have demonstrated above thatthe unity here attained is purely verbal, since we cannot succeed insuppressing the essential differences of things. 4. Now comes an affirmation on the genesis of things. After havingadmitted that the object is an idea of the mind, one of itsmanifestations, or one of its moods, the idealists go so far as to saythat the consciousness is the generating power of ideas, and, consequently, the generating cause of the universe. It is thoughtwhich creates the world. That is the final conclusion. I indicated, beforehand, in the chapters on the definition ofsensation and on the distinction between the consciousness and theobject, the reasons which lead me to reject the premises of idealism. It will be sufficient to offer here a criticism on its lastconclusion: "It is the mind that creates the world. " This thesis strikes at the duality--consciousness and object; it givesthe supremacy to the consciousness by making of the object an effector property of the former. We can object that this genesis cannot beclearly represented, and that for the very simple reason that it isimpossible to clearly accept "mind" as a separate entity and distinctfrom matter. It is easy to affirm this separation, thanks to thepsittacism of the words, which are here used like counterfeit coin, but we cannot represent it to ourselves, for it corresponds tonothing. The consciousness constitutes all that is mental in theworld; nothing else can be described as mental. Now this consciousnessonly exists as an act; it is, in other terms, an incomplete form ofexistence, which does not exist apart from its object, of which thetrue name is matter. It is therefore very difficult to understand thisaffirmation, "It is the mind that creates the world, " since to be ableto do so, we should have to imagine a consciousness without an object. Moreover, should we even succeed in doing so, we should be none themore disposed, on that account, to give assent to this proposition. Consciousness and matter represent to us the most different andantithetical terms of the whole of the knowable. Were the hypothesisto be advanced that one of these elements is capable of engenderingthe other, we should immediately have to ask ourselves why thisgenerating power and this pre-eminence should be attributed to onerather than to the other element. Who can claim that one solution ismore clear, more reasonable, or more probable than the other? One of the great advantages of the history of philosophy here assertsitself. This history shows us that different minds when reflecting onthe same problems have come to conceive solutions which have appearedto them clear, and consequently were possible; now, as these solutionsare often contradictory, nothing shows better than their collation thedistance between possibility and fact. Thus the materialists, who, like the idealists, have put forward a genetic theory of the mind, have conceived mind as produced by matter;--a conception diametricallyopposed to that of the idealists. It may be said that these twoconceptions, opposed in sense, annul each other, and that each ofthese two philosophical systems has rendered us service bydemonstrating the error of the opposing system. FOOTNOTES: [Footnote 43: It is, perhaps, needless to point out that by"spiritualism" M. Binet does not mean the doctrine of thespirit-rappers, whom he, like other scientific writers, designates as"spiritists, " but the creed of all those who believe in disembodiedspirits or existences. --ED. ] [Footnote 44: I do not insist on the difference between my conceptionand the spiritualistic conception; my distinction betweenconsciousness and matter does not correspond, it is evident, to thatof "facts of consciousness" and "physical facts" which spiritualismsets up. ] [Footnote 45: _Archives de Psychologie_, vol. Iv. No. 14, Nov. 1904, p. 132 (article on Panpsychism). ] CHAPTER III MATERIALISM AND PARALLELISM Materialism is a very ancient doctrine. It is even the most ancient ofall, which simply proves that amongst the different explanations givenof our double physico-mental nature, this doctrine is the easiest tounderstand. The origin of materialism is to be found in the beliefs ofsavage tribes, and is again found, very clearly defined, in thephilosophy of those ancient Greeks who philosophized before Plato andAristotle. A still stranger fact is that the thoughts of a greatnumber of the Fathers of the Church inclined towards the philosophy ofmatter. Then, in the course of its evolution, there occurred a momentof eclipse, and materialism ceased to attract attention till thecontemporary period in which we assist at its re-birth, Nowadays, itconstitutes a powerful doctrine, the more so that it hassurreptitiously crept into the thoughts of many learned men withouttheir being clearly conscious of it. There are many physicists andphysiologists who think and speak as materialists, though they havemade up their minds to remain on the battle-ground of observed factsand have a holy horror of metaphysics. In a certain sense, it may besaid that materialism is the metaphysics of those who refuse to bemetaphysicians. It is very evident that in the course of its long history, materialismhas often changed its skin. Like all knowledge, it has been subject tothe law of progress; and, certainly, it would not have been of anature to satisfy the intellectual wants of contemporary scholars, hadit not stripped itself of the rude form under which it firstmanifested itself in the mind of primitive man. Yet what has enabledthe doctrine to keep its unity through all its changes is that itmanifests a deeply human tendency to cling by preference to everythingvisible and tangible. Whatever strikes the eyes, or can be felt by the hand, seems to us inthe highest degree endowed with reality or existence. It is only muchlater, after an effort of refined thought, that we come to recognisean existence in everything that can be perceived in any way whatever, even in an idea. It is still later that we understand that existenceis not only that which is perceived but also that which is linkedlogically with the rest of our knowledge. A good deal of progress hasbeen necessary to reach this point. As I have not the slightest intention of giving even an abridgedhistory of materialism, let us come at once to the present day, andendeavour to say in what consists the scientific form this doctrinehas assumed. Its fundamental basis has not changed. It still rests onour tendency to give chief importance to what can be seen and touched;and it is an effect of the hegemony of three of our senses, thevisual, the tactile, and the muscular. The extraordinary development of the physical sciences has no doubtgiven an enormous encouragement to materialism, and it may be saidthat in the philosophy of nature it occupies a principal place, andthat it is there in its own domain and unassailable. It has become the expression of the idea that everything that can beexplained scientifically, everything susceptible of being measured, isa material phenomenon. It is the representation of the materialexplanation pushed to its last limits, and all experiments, allcalculations, all inductions resting on the grand principle of theconservation of matter and energy plead in its favour. We will examine with some precision how far such a doctrine solves theproblem of the existence of the intellectual functions. The doctrine has understood this connection as being purely material, and has sought its image in other phenomena which are entirely so. Thus, it has borrowed from physiology the principle of itsexplanation, it has transported into the domain of thought the idea offunction, and it has supposed that the soul is to the body in therelation of function to organ. Intelligence would thus be a cerebralfunction. To explain intelligence, materialists link it with matter, turn it into a property of matter, and compare it to a movement ofmatter, and sometimes even to a secretion. So Karl Vogt, theillustrious Genevan naturalist, one day declared, to the great scandalof every one, that the brain secretes the thought as the kidney doesurine. This bold comparison seemed shocking, puerile, and false, for asecretion is a material thing while thought is not. Karl Vogt alsoemployed another comparison: the brain produces the thought as themuscle produces movement, and it at once seems less offensive tocompare the thought to a movement than to compare it to a liquidsecretion. At the present day, an illustration still more vague wouldbe used, such as that of a transformation of energy: chemical energydisengaged by the nerve centres would be thus looked upon astransformed into psychical energy. However, it matters little what metaphors are applied to for help inexplaining the passage from the physical to the mental. Whatcharacterises materialist philosophy is its belief in the possibilityof such a passage, and its considering it as the genesis of thought. "One calls materialist, " says Renouvier, with great exactness, "everyphilosophy which defines thought as the product of a compound whoseelements do not imply thought. " A sweeping formula which allows us toforesee all the future avatars of the materialist doctrine, and toclass them beforehand in the same category. The criticisms which have been directed against materialism are all, or nearly all, variations of the principle of heterogeneity. We willnot dwell long on this, but simply recollect that, according to thisprinciple, it is impossible to attribute to the brain the capacity ofgenerating consciousness. Physical force can indeed generate physicalforce under the same or a different form, and it thus produces all theeffects which are determined by the laws of nature. But it isimpossible to comprehend how physical force can enrich itself at agiven moment by a conscious force. Physical force is reduced tomovements of bodies and to displacements of atoms; how could a changeof position in any inert objects give rise to a judgment, a reasoning, or any phenomenon of the consciousness? It is further said: this ideaof function, which materialists here introduce to render morecomprehensible the passage from a material body to a spiritual action, contains only an empty explanation, for the function is notessentially distinct by its nature from the organ; it is simply "theorgan in activity, " it adds to the organ taken in a state of reposebut one change, viz. Activity, that is to say movement, and, consequently, the function of an organ is material by the same rightas the organ. When a muscle contracts, this contraction, which is theproper function of the muscular fibre, consists in a condensation ofthe muscular protoplasm, and this condensation is a material fact. When a gland enters into activity, a certain quantity of liquid flowsinto the channels of the gland, and this liquid is caused by aphysical and chemical modification of the cellular protoplasm; it is amelting, or a liquefaction, which likewise is material. The functionof the nerve cell is to produce movement, or to preserve it, or todirect it; ii is material like the cells. There is therefore nothingin all those functional phenomena which might lead us to understandhow a material cause should be capable of engendering a consciouseffect. It seems that all materialists have acknowledged that here is thevulnerable point in their theory, for it is the principle ofheterogeneity which they have especially combated. But their defenceis wanting in frankness, and principally consists in subterfuges. In brief, it affirms that we are surrounded with mystery, that we arenot sufficiently learned to have the right to impose limits to thepower of matter, and to say to it: "Thou shalt not produce thisphenomenon. " A materialist theologian declares that he sees noimpossibility in stones thinking and arguing, if God, in His infinitepower, has decided to unite thought with brute matter. This argumentis not really serious; it demands the intervention of so powerful a_Deus ex machina_, that it can be applied equally to all problems; tosolve all is to solve none. Modern materialists rightly do not bring God into the question. Theirmode of argument takes another form; but it remains to be seen if, atbottom, it is not the same as the other. It simply consists inaffirming that up till now we know certain properties of matter only, but that science every day discovers new ones; that matter is areservoir of unknown forces, and that it is not impossible that theorigin of psychical forces may yet be discovered in matter. This ideais clearly hinted at by Littré. The physicist Tyndall gave it adefinite formula when he uttered at the Belfast Congress this phraseso often quoted: "If I look back on the limits of experimentalscience, I can discern in the bosom of that matter (which, in ourignorance, while at the same time professing our respect for itsCreator, we have, till now, treated with opprobrium) the promise andthe power of all forms and qualities of life. " The opponents of the doctrine have not ceased to answer that thematter of to-morrow, like the matter of to-day, can generate none butmaterial effects, and that a difficulty is not solved by putting offits solution to some indefinite date in our scientific evolution: andit certainly seems that the counter-stroke is decisive, if we admitthe principle of heterogeneity with its natural consequence. We will now criticise the above doctrine by making use of the ideas Ihave above enunciated. The criticism we have to apply to materialismis not the same as that just summarised. The axis of the discussionchanges its position. In the first place, I reproach materialism with presenting itself as atheory of the generation of the consciousness by the object. We havealready reproached idealism with putting itself forward as a theory ofthe generation of the object by the consciousness. The error of thetwo systems is produced in a converse direction, but is of the samegravity. The consciousness and its object, we say yet again, constitute the widest division it is possible to effect in the domainof cognition; it is quite as illegitimate to reduce the first term tothe second as to reduce the second to the first. To reduce one to theother, by way of affiliation or otherwise, there must first bediscovered, then, an identity of nature which does not exist. In the second place, when one examines closely the explanationmaterialism has imagined in order to derive thought from an action ofmatter, it is seen that this representation is rendered completelyimpossible by all we know of the nature of thought. For thematerialist to suppose for one moment that thought is a cerebralfunction, he must evidently make an illusion for himself as to whatthought is, and must juggle with concepts. Perhaps, could we penetrateinto his own inmost thought, we should discover that at the moment hesupposes a mere cell can manufacture the phenomena of consciousness, some vague image suggests itself to him whereby he identifies thesephenomena with a light and subtle principle escaping from the nervecell, something which resembles an electric _effluve_, or awill-of-the-wisp, or the flame from a punch-bowl. [46] I cannot, of course, tell whether my supposition is correct. But whatI assert, with the calmness of perfect certitude, is that thematerialist has not taken the pains to analyse attentively what hecalls the phenomenon of consciousness. Had he made this analysis andkept the elements in his mind, he would have seen that it is almostimpossible to hook in any way a phenomenon of consciousness on to amaterial molecule. In fact, also, to take this into account, we will not remain withinthe vagueness of the concept, but will take a particular example toargue upon, viz. That of an external perception. I open my window on afine day, and I see before me a sunny plain, with, as far as the eyecan reach, houses amongst the trees, and again more houses, the mostdistant of which are outlined against my far-off horizon. This is mymental phenomenon. And while I am at my window, my eyes fixed on theview, the anatomist declares that, starting from my retina, molecularvibrations travel along the optic nerve, cross each other at thechiasma, enter into the fascia, pass through the internal capsule andreach the hemispheres, or rather the occipital regions, of the brain, where, for the moment, we agree to localise the centre of projectionof the visual sensations. This is my physical phenomenon. It nowbecomes the question of passing from this physical phenomena to themental one. And here we are stopped by a really formidabledifficulty. My mental phenomenon is not entirely mental, as is usually supposedfrom the deceitful brevity of the phrase. It is in great partphysical, for it can be decomposed into two elements, a consciousnessand its object; and this object of the consciousness, this group oflittle houses I see in the plain, belongs to sensation--that is tosay, to something physical--or, in other words, to matter. Let us examine in its turn the physical process which is supposed tobe discovered in my nervous centres while I am in course ofcontemplating the landscape. This pretended physical process itself, quite as much as my conscious perception of the landscape, is aphysico-psychical phenomenon; for my cerebral movements are perceived, hypothetically at least, by an observer. This is a perception, consequently it can be decomposed into two things, a consciousness andits object. As a further consequence, when we wish, by a metaphysicaleffort, to attach the consciousness to a material state of the brainand to establish a link between the two events, it will be found thatwe wrongly hook one physico-mental phenomenon on to another. But, evidently, this objection is not a refutation. We may if wechoose suppose that the so-called cerebral process is capable ofsubsisting at moments when no one perceives it, and that it exists ofitself, is sufficient for itself, and is entirely physical. But canwe subject the mental process of perception to the same purification?Can we separate these two elements, the consciousness and its object, retain the element consciousness and reject the element object, whichis physical, thus constituting a phenomenon entirely mental, whichmight then be possibly placed beside the entirely physical phenomenon, so as to study their relation to each other? This is quite impossible, and the impossibility is double, for it exists _de facto_ and _dejure_. _De jure_, because we have already established that a consciousnessempty and without object cannot be conceived. _De facto_, because theexistence of the object that consciousness carries with it is veryembarrassing for the materialist; for this object is material, and asreal and material as the fibres and cells of the brain. It might, indeed, be supposed that by transformation or otherwise there goesforth from the cerebral convolution a purely psychical phenomenonresembling a wave. But how can we conceive the transformation of thisconvolution into a semi-material phenomenon? How can we comprehendthat there should issue from this convolution the material object of aperception--for example, a plain dotted with houses? An English histologist remarked one day, with some eloquence, howlittle the most minute study of the brain aided us to understandthought. He was thus answering Auguste Comte, who, in a moment ofaberration, claimed that psychology, in order to become a science, ought to reject the testimony of the consciousness, and to useexclusively as its means of study the histology of the nerve centresand the measurement of the cranium. Our histologist, who had passedpart of his life examining, under the microscope, fragments ofcerebral matter, in following the forms of the cells, the course ofthe fibres, and the grouping and distribution of the fascia, made thefollowing remark: "It is the fact that the study, however patient, minute, and thorough it might be, of this nerve-skein can never enableus to know what a state of consciousness is, if we do not know itotherwise; for never across the field of the microscope is there seento pass a memory, an emotion, or an act of volition. " And, he added, "he who confines himself to peering into these material structuresremains as ignorant of the phenomena of the mind as the London cabmanwho, for ever travelling through the streets of the great city, isignorant of what is said and what is going on in the interior of thehouses. " This picturesque comparison, the truth of which has neverbeen questioned, is based on this supposition, that the psychical actis entirely immaterial and invisible, and therefore escapes thepiercing eye of the microscope. But a deeper analysis of the mindshows how little exact is this assertion. From the moment eachpsychical act implies a material object, we can ask ourselves twothings: (1) Why is it that the anatomist does not discover thesematerial objects in the interior of the brain? We ought to see them, for they are material, and therefore visible. We ought to see themwith their aspect and colour, or be able to explain why they are notseen. In general, all that is described to us in the brain is themolecular vibrations. But we are not conscious of them. Where, then, is that of which we are conscious? (2) It should next be explained tous by what elaboration, transmutation, or metamorphosis a moleculardisturbance, which is material, can transform itself into the objectswhich are equally material. This is the criticism we have to address to materialism. Until proofto the contrary, I hold it to be irrefutable. PARALLELISM For this exposition to follow the logical order of ideas, thediscussion on materialism should be immediately succeeded by that onparallelism. These two doctrines are near akin; they resemble eachother as the second edition of a book, revised and corrected, resembles the first. Parallelism is the materialist doctrine of thoseforewarned folk, who have perceived the errors committed and endeavourto avoid them, while cherishing all that can be saved of the condemneddoctrine. That which philosophers criticised in materialism was themisunderstanding of the principle of heterogeneity. The parallelistshave seen this mistake, and have taken steps to respect thisprinciple: we shall see in what way. They are especially prudent, andthey excel in avoiding being compromised. They put forth theirhypothesis as a provisional one, and they vaunt its convenience. Itis, say they, a practical method of avoiding many difficulties; itbecomes for philosophers an equivalent of that phrase which so manytimorous ministers repeat: "Above all, no scrapes!" Let us study the exact point on which parallelism has amendedmaterialism. We have seen that every materialist doctrine is theexpression of this idea, that physical phenomena are the only onesthat are determined, measurable, explicable, and scientific. This ideadoes wonders in the natural sciences, but is at fault when, from thephysical, we pass into the moral world, and we have seen how thematerialistic doctrine fails when it endeavours to attach the physicalto the mental. There are then two great difficulties which thematerialistic explanation finds before it; one is a difficulty ofmechanism and the other of genesis. By connecting the mind with thebrain, like a function to its organ, this doctrine seeks to solvethese two problems, and with what little success we have seen. Parallelism, has tried to avoid these two problems; not only does itnot solve them, but it arranges so as not to propound them. Theexpedient adopted consists in avoiding the meeting of the physical andthe mental; instead of placing them end to end and welding one to theother, they are placed in parallel fashion side by side. To explaintheir correlation, which so many observations vaguely demonstrate, thefollowing hypothesis is advanced. Physical and psychical life form twoparallel currents, which never mingle their waters; to every state ofdefinite consciousness there corresponds the counterpart of an equallydefinite state of the nerve centres; the fact of consciousness has itsantecedents and its consequences in the consciousness; and thephysical fact equally takes its place in a chain of physical facts. The two series are thus evolved, and correspond strictly to each otheraccording to a necessary law; so that the scholar who was perfectlyinstructed, and to whom one of these states was presented, coulddescribe its fellow. But never does any of the terms of one seriesinfluence the terms of the other. Observation and the testimony of the consciousness seem to attest thisdual progress; but they are, according to the parallelist hypothesis, illusions. When I move my arm by a voluntary act, it is not my will, _qua_ act of consciousness, which determines the movement of thearm--for this is a material fact. The movement is produced by thecoming into play of groups of muscles. Each muscle, composed of asemi-fluid substance, being excited, contracts in the direction of itsgreatest length. The excitant of the muscles is also a material fact, a material influx which starts from the motor cells of the encephalon, and of which we know the course down through the pyramidal fascium, the anterior roots of the spinal cord, and the nerves of the peripheryto its termination in the motor plates of the muscles. It is thisexcitement which is the physical, direct, and veritable cause ofvoluntary movements. And it is the same with all acts and signs, allexpressions of our conscious states; the trembling of fear, theredness of anger, the movements of walking, down to the words weutter--all these are physical effects produced by physical processes, which act physically, and of which the mental counterpart has initself no effective action. Let it be understood that I am here pointing out one of the forms, andthat the most usual, of the parallelist theory. Each author varies itaccording to his fancy; some widen the correspondence between thephysical and the moral, others prefer to narrow it. At one time avague relation is supposed which is only true on a large scale, and isa union rather than an equivalence. At another, it is an exactcounterpart, a complete duplicate in which the smallest physical eventcorresponds to a mental one. In one of the forms of this theory that has been recently invented, parallelists have gone so far as to assert that there exists no realcohesion in the mental chain, and that no mental phenomenon can havethe property of provoking another mental phenomenon by an act of truecausality. It is within the nervous tissue, they say, that the nexusof psychic states should be enclosed. These should succeed in timewithout being directly connected with one another; they should succeedbecause the physical basis of them is excited in succession. Some ofthem would be like an air on the piano: the notes follow each otherand arrange themselves into melodies, not by any affinity proper tothemselves, but because the keys of the instrument are struck in therequired order. I said a little while ago that parallelism was a perfectedmaterialism. The reason of this will be understood. It is a doctrinewhich preserves the determinism of physical facts while avoiding thecompromising of itself in the difficult explanation of the connectionbetween the soul and the body. It remains scientific without raising ametaphysical heresy. Bain is one of those who have most clearly expressed, not only theadvantages, but also the aspirations of this theory (_Mind and Body_, p. 130):-- "We have every reason for believing, " he says, "that there is in companywith all our mental processes, _an unbroken material succession_. Fromthe ingress of a sensation, to the outgoing responses in action, themental succession is not for an instant dissevered from a physicalsuccession. A new prospect bursts upon the view; there is mental resultof sensation, emotion, thought--terminating in outward displays ofspeech or gesture. Parallel to this mental series is the physical seriesof facts, the successive agitation of the physical organs, called theeye, the retina, the optic nerve, optic centres, cerebral hemispheres, outgoing nerves, muscles, &c. While we go the round of the mental circleof sensation, emotion, and thought, there is an unbroken physical circleof effects. It would be incompatible with everything we know of thecerebral action, to suppose that the physical chain ends abruptly in aphysical void, occupied by an immaterial substance; which immaterialsubstance, after working alone, imparts its results to the other edgeof the physical break, and determines the active response--two shores ofthe material with an intervening ocean of the immaterial. There is, infact, no rupture of nervous continuity. The only tenable supposition is, that mental and physical proceed together, as undivided twins. " On reading this passage it is easy to see the idea which forms thebasis of the doctrine. It is, as I have already said, the fetichism ofmechanics: parallelism takes its inspiration from this quite asdirectly as does materialism, but with more skill, inasmuch as itavoids the most dangerous question, that of the interaction of physicsand morals, and replaces it by an hypothesis much resemblingLeibnitz's hypothesis of the pre-established harmony, On the otherhand, a second merit of this prudent doctrine is the avoiding thequestion of genesis. It does not seek for the origin of thought, butplaces this last in a relation of parallelism with the manifestationsof matter; and in the same way that parallel lines prolonged _adinfinitum_ never meet, so the partisans of this doctrine announcetheir resolution not to inquire how the actual state of things hasbeen formed, nor how it will end if, for example, one of the termsshould disappear by the death of the bodily organism. Notwithstanding so many precautions, criticisms have not been wanting;only they would seem not to have touched the weak part of thedoctrine and not to be decisive. We will only run through thembriefly. It has been said: there is no logical necessity which forces us torefuse to the consciousness the privilege of acting in completeindependence of the nervous mechanism. It has also been said: it is by no means certain that any nervousmechanism can be invented which imitates and, if need were, couldreplace an intellectual act. For instance, what association of nervecells, what molecular action, can imitate an act of comparison whichenables us to see a resemblance between two objects? Let it besupposed, for example, that the resemblance of two impressions comefrom a partial identity, and that the latter has for material supportan identity in the seat or the form of the corresponding nervousinflux. But what is identity? How can it be conceived withoutsupposing resemblance, of which it is but a form? How, then, can theone be explained by the other? Thus, for instance, at the bottom ofall our intellectual acts, there is a certain degree of belief. Canany material combination be found which corresponds thereto? There is one last objection, the most serious of all. Parallelism, byestablishing a fixed and invariable relation between the physical andthe moral, ends by denying the rôle of this last, since the physicalmechanism is sufficient to draw to itself all the effects whichgeneral belief attributes to the moral. The parallelists on this pointgo very much further than the materialists; the latter at leastconcede that the consciousness is of some use, since they compared itto a function or a secretion, and, after all, a secretion is a usefulliquid. The parallelists are so strongly convinced that mechanism isalone efficacious that they come to deny any rôle to thought. Theconsciousness for them has no purpose: yet it keeps company with itsobject. The metaphors which serve to define it, part of which havebeen imagined by Huxley, are all of a passive nature. Such is thelight, or the whistling noise which accompanies the working of anengine, but does not act on its machinery. Or, the shadow which dogsthe steps of the traveller. Or a phosphorescence lighting up thetraces of the movements of the brain. It has also been said that the consciousness is a useless luxury. Somehave even gone further, and the fine and significant name of_epiphenomenon_, that has been given to thought, well translates thatconception, according to which semi-realities may exist in nature. All these objections certainly carry great weight, but they are notcapable of killing the doctrine--they only scotch it. I think there is a radical vice in parallelism, which till now has notbeen sufficiently indicated, and I ask what can really remain of thewhole edifice when this vice has been once exposed? Parallelism implies a false idea, which we have already come acrosswhen discussing materialism. It is the idea that a phenomenon ofconsciousness constitutes one complete whole. The error proceeds from the use of concepts which cause the reality tobe lost sight of. The reality shows that every phenomenon ofconsciousness consists in a mode of activity, an aggregate offaculties which require an object to fasten on to and so realisethemselves, and that this object is furnished by matter. What wealways note in intuition is the union, the incarnation ofconsciousness-matter. Our thoughts, our memories, our reasonings haveas object sensations, images--that is to say, things which, strictlyspeaking, are as material as our own brains. It is therefore ratherchildish to put all these workings of the spirit on another plane andin another world than the workings of the brain since they are ingreat part of the same nature as the last named and they contain somany material elements. Now if we re-establish facts as they are, ifwe admit a parallelism between physical phenomena, on the one hand, and phenomena at once physical and psychical, on the other, theparallelist hypothesis loses every sort of meaning. It ceases topresent to us the image of two phenomena of an absolutely differentorder, which are found coupled together like the two faces of a unity, the front and back of a page, the right and wrong side of a stuff. Ifthere is anything material in the psychical part, the opposition ofnature no longer exists between the two terms; they become identical. Very often, certain parallelists, after thinking they have discoveredthe duality of nature, endeavour to bring it back to unity bysupposing that the two faces of the reality are as two effects of oneunique reality, inaccessible to our senses and underlying appearances. Why go so far afield to seek unity? It is trouble in vain: for it isto be found in the phenomenon itself. FOOTNOTES: [Footnote 46: I can quote two observations in support of this. M. BRIEUX, to whom I was relating this part of my argument, stopped me, saying, "You have guessed right; I represent to myself thought issuingfrom brain in the form of an electric gleam. " Dr. SIMON also informedme, during the reading of my manuscript, that he saw "thought floatingover the brain like an _ignis fatuus_. "] CHAPTER IV MODERN THEORIES It may be thought that the objection taken above to parallelism andmaterialism is personal to myself, because I have put it forward asthe consequence of my analysis of the respective shares of thought andmatter in every act of cognition. This is not so. I am here in harmonywith other philosophers who arrived at the same conclusions longbefore me, and it may be useful to quote them. We will begin with the prince of idealists, Berkeley. "'Everything youknow or conceive other than spirits, ' says Philonous to Hylas, 'is butyour ideas; so then when you say that all ideas are occasioned byimpressions made in the brain, either you conceive this brain or youdo not. If you conceive it, you are in that case talking of ideasimprinted in an idea which is the cause of this very idea, which isabsurd. If you do not conceive it, you are talking unintelligibly, youare not forming a reasonable hypothesis. ' 'How can it be reasonable, 'he goes on to say, 'to think that the brain, which is a sensiblething, _i. E. _ which can be apprehended by the senses--an ideaconsequently which only exists in the mind--is the cause of our otherideas?'"[47] Thus, in the reasoning of Berkeley, the function of the brain cannotexplain the production of ideas, because the brain itself is an idea, and an idea cannot be the cause of all our other ideas. M. Bergson's argument is quite similar, although he takes a verydifferent standpoint from that of idealism. He takes the word image inthe vaguest conceivable sense. To explain the meaning of this word hesimply says: "images which are perceived when I open my senses, andunperceived when I close them. " He also remarks that the externalobjects are images, and that the brain and its molecular disturbancesare likewise images. And he adds, "For this image which I callcerebral disturbance to generate the external images, it would have tocontain them in one way or another, and the representation of thewhole material universe would have to be implicated in that of thismolecular movement. Now, it is enough to enunciate such a propositionto reveal its absurdity. "[48] It will be seen that this reasoning is the same as Berkeley's, thoughthe two authors are reasoning on objects that are different; accordingto Berkeley, the brain and the states of conscience are psychicalstates; according to Bergson, the definition of the nature of thesetwo objects designated by the term image is more comprehensive, butthe essential of his argument is independent of this definition. It isenough that the two terms should be of similar nature for one to beunable to generate the other. My own argument in its turn comes rather near the preceding ones. Forthe idea of Berkeley, and the image of Bergson, I substitute the termmatter. I say that the brain is matter, and that the perception of anyobject is perception of matter, and I think it is not easy to explainhow from this brain can issue this perception, since that would be toadmit that from one matter may come forth another matter. There iscertainly here a great difficulty. M. Bergson has thought to overcome it by attacking it in the followingway. He has the very ingenious idea of changing the position of therepresentation in relation to the cerebral movement. The materialistplaces the representation after this movement and derives it from themovement; the parallelist places it by the side of the movement and inequivalence to it. M. Bergson places it before the movement, andsupposes it to play with regard to it the part of exciting cause, orsimply that of initiator. This cerebral movement becomes an effect ofthe representation and a motor effect. Consequently the nervous systempasses into the state of motor organ: the sensory nerves are not, assupposed, true sensory nerves, but they are the commencements of motornerves, the aim of which is to lead the motor excitements to thecentres which play the part of commutators and direct the current, sometimes by one set of nerves, sometimes by others. The nervoussystem is like a tool held in the hand: it is a vehicle for action, weare told, and not a substratum for cognition. I cannot here say withwhat ingenuity, with what powerful logic, and with what closecontinuity of ideas M. Bergson develops his system, nor with whataddress he braves its difficulties. His mind is remarkable alike for its power of systematisation and itssuppleness of adaptation. Before commencing to criticise him, I amanxious to say how much I admire him, how much I agree with himthroughout the critical part of his work, and how much I owe to theperusal of his book, _Matière et Mémoire_. Though I was led intometaphysics by private needs, though some of the ideas I have setforth above were conceptions of my own (for example, the criticism ofthe mechanical theory of matter, and the definition of sensation), before I had read M. Bergson's book, it cannot be denied that itsperusal has so strongly modified my ideas that a great part of theseare due to him without my feeling capable of exactly discerning which;for ideas have a much more impersonal character than observations andexperiments. It would therefore have been ungrateful to criticise himbefore having rendered him this tribute. There are, in M. Bergson's theory, a few assertions which surprise usa little, like everything which runs counter to old habits. It hasalways been supposed that our body is the receptacle of ourpsychological phenomena. We store our reminiscences in our nervecentres; we put the state of our emotions in the perturbations ofcertain apparatus; we find the physical basis of our efforts of willand of attention in the sensations of muscular tension born in ourlimbs or trunk. Directly we believe that the nervous system is nolonger the depository of these states, we must change their domicile;and where are they to be placed? Here the theory becomes obscure andvague, and custom renders it difficult to understand the situation ofthe mind outside the body. M. Bergson places memory in planes ofconsciousness far removed from action, and perception he places in thevery object we perceive. If I look at my bookcase, my thought is in my books; if I look at thesky, my thought is in a star. [49] It is very difficult to criticiseideas such as these, because one is never certain that one understandsthem. I will therefore not linger over them, notwithstanding themistrust which they inspire in me. But what seems to me to require proof is the function M. Bergson isled to attribute to the sensory nerves. To his mind, it is not exactto say that the excitement of a sensory nerve excites sensation. Thiswould be a wrong description, for, according to him, every nerve, evena sensory one, serves as a motor; it conducts the disturbance which, passing through the central commutator, flows finally into themuscles. But then, whence comes it that I think I feel a sensationwhen my sensory nerve is touched? Whence comes it that a pressure onthe epitrochlear nerve gives me a tingling in the hand? Whence comesit that a blow on the eyeball gives me a fleeting impression of light?One must read the page where M. Bergson struggles against what seemsto me the evidence of the facts. "If, for one reason or another, " hesays, "the excitement no longer passes, it would be strange if thecorresponding perception took place, since this perception would thenput our body in relation with points of space which would no longerinvite it to make a choice. Divide the optic nerve of any animal; thedisturbance starting from the luminous point is no longer transmittedto the brain, and thence to the motor nerves. The thread whichconnected the external object to the motor mechanism of the animal byenveloping the optic nerve, is severed; the visual perception hastherefore become powerless, and in this powerlessness consistsunconsciousness. " This argument is more clever than convincing. It isnot convincing, because it consists in exaggerating beyond all reasona very real fact, that of the relation which can be discovered betweenour sensations and our movements. We believe, with M. Bergson, that itis absolutely correct to see in action the end and the _raison d'être_of our intelligence and our sensibility. But does it follow that everydegree, every shade, every detail of sensation, even the mostinsignificant, has any importance for the action? The variations ofsensibility are much more numerous than those of movements and ofadaptation; very probably, as is seen in an attentive study ofinfancy, sensibility precedes the power of motion in itsdifferentiations. A child shows an extraordinary acuteness ofperception at an age when its hand is still very clumsy. Thecorrelation, then, is not absolute. And then even if it were so, itwould not follow that the suppression of any movement would produce byrebound the suppression of the sensation to which this movementhabitually corresponds. On this hypothesis, a sensation which losesits motor effect becomes useless. Be it so; but this does not provethat the uselessness of a sensation is synonymous with insensibility. I can very well imagine the movement being suppressed and the uselesssensation continuing to evoke images and to be perceived. Does notthis occur daily? There are patients who, after an attack of paralysisremain paralysed in one limb, which loses the voluntary movement, butdoes not necessarily lose its sensibility. Many clear cases areobserved in which this dissociation takes place. I therefore own that I cannot follow M. Bergson in his deduction. As aphysiologist, I am obliged to believe firmly in the existence of thesensory nerves, and therefore I continue to suppose that our conscioussensations are consequent to the excitement of these nerves andsubordinate to their integrity. Now, as therein lies, unless Imistake, the essential postulate, the heart of M. Bergson's theory, bynot admitting it I must regretfully reject the whole. FOOTNOTES: [Footnote 47: I borrow this quotation from RENOUVIER, _LePersonnellisme_, p. 263. ] [Footnote 48: _Matière et Mémoire_, p. 3. The author has returned tothis point more at length in a communication to the Congrès dePhilosophie de Génève, in 1904. See _Revue de Métaphysique et deMorale_, Nov. 1904, communication from H. BERGSON entitled "LeParalogisme psycho-physiologique. " Here is a passage from this articlewhich expresses the same idea: "To say that the image of thesurrounding world issues from this image (from the cerebral movement), or that it expresses itself by this image, or that it arises as soonas this image is suggested, or that one gives it to one's self bygiving one's self this image, would be to contradict one's self; sincethese two images, the outer world and the intra-cerebral movement, have been supposed to be of the same nature, and the second image is, by the hypothesis, an infinitesimal part of the field ofrepresentation, while the first fills the whole of it. "] [Footnote 49: _Matière et Mémoire_, p. 31] CHAPTER V CONCLUSION A few convinced materialists and parallelists, to whom I have read theabove criticisms on their systems, have found no answer to them; mycriticisms have appeared to them just, but nevertheless they havecontinued to abide by their own systems, probably because they werebound to have one. We do not destroy an erroneous idea when we do notreplace it by another. This has decided me to set forth some personal views which, provisionally, and for want of better, might be substituted for theold doctrines. Before doing this, I hasten to explain their character, and to state openly that they are only hypotheses. I know that metaphysicians rarely make avowals of this kind. Theypresent their systems as a well-connected whole, and they set forthits different parts, even the boldest of them, in the same dogmatictone, and without warning that we ought to attach very unequal degreesof confidence to these various parts. This is a deplorable method, andto it is perhaps due the kind of disdain that observers andexperimentalists feel for metaphysics--a disdain often withoutjustification, for all is not false, and everything is nothypothetical, in metaphysics. There are in it demonstrations, analyses, and criticisms, especially the last, which appear to me asexact and as certain as an observation or experiment. The mistake liesin mixing up together in a statement, without distinction, the certainwith the probable, and the probable with the possible. Metaphysicians are not wholly responsible for this fault of method;and I am much inclined to think that it is the natural consequence ofthe abuse of speculation. It is especially by the cultivation of thesciences of observation that we foster in ourselves the precious senseof proof, because we can check it any minute by experimentalverification. When we are working at a distance from the facts, thissense of proof gets thinner, and there is lost that feeling ofresponsibility and fear of seeing one's assertions contradicted by adecisive countervailing observation, which is felt by every observer. One acquires the unbearable pride which I note in Kant, and oneabandons one's self to the spirit of construction. I am speaking frompersonal experience. I have several times detected within me this badspirit of construction, I have been seeking to group several facts ofobservation under the same idea, and then I have discovered that I wasbelittling and depreciating those facts which did not fit in with theidea. The hypothesis I now present on the relations of the mind and thebrain has, for me, the advantage of bringing to light the preciseconditions which a solution of this great problem must satisfy forthis solution to be worthy of discussion. These conditions are very numerous. I shall not indicate them allsuccessively; but here are two which are particularly important. 1. The manifestations of the consciousness are conditioned by thebrain. Let us suspend, by any means, the activity of the encephalicmass, by arresting the circulation of the blood for example, and thepsychic function is at once inhibited. Compress the carotid, and youobtain the clouding-over of the intellect. Or, instead of a totalabolition, you can have one in detail; sever a sensory nerve with thebistoury, and all the sensations which that nerve transmits to thebrain are suppressed. Consciousness appears only when the moleculardisturbance reaches the nerve centres; everything takes place in thesame way as if this disturbance released the consciousness. Consciousness also accompanies or follows certain material states ofthe nerve centres, such as the waves which traverse the sensorynerves, which exercise reflex action in the cells, and which propagatethemselves in the motor nerves. It is to the production, thedistribution, and the integrity of this nervous influx that theconsciousness is closely linked. It there finds one of the conditionsof its apparition. 2. On the other hand, the consciousness remains in complete ignoranceof these intra-cerebral phenomena. It does not perceive the nerve-wavewhich sets it in motion, it knows nothing of its peculiarities, of itstrajectory, or the length of its course. In this sense it may be saidthat it is in no degree an anatomist; it has no idea of all thepeculiarities of the nerve-wave which form part of its cerebralhistory from the moment when these peculiarities are out of relationwith the properties of external objects. One sometimes wonders that our consciousness is not aware that theobjects we perceive with our two eyes correspond to a doubleundulation, namely, that of the right and that of the left, and thatthe image is reversed on the retina, so that it is the rods of theright which are impressed by objects on our left, and the rods of theupper part by objects below our eyes. These are, it has been veryjustly said, factitious problems, imaginary difficulties which do notexist. There is no need to explain, for instance, direct vision by areversed image, because our consciousness is not aware that the imageon the retina is reversed. In order to take account of this, we shouldrequire another eye to see this image. This answer appearsparticularly to the point. It will be found that it is absolutelycorrect if we reflect that this case of the unfelt inversion of theimage on the retina is but one example of the anatomical ignorance ofthe consciousness. It might also be declared, in the same order of ideas, that ourconsciousness is ignorant, that excitements of the eye cross eachother at the level of the chiasma, and pass through the internalcapsule, and that the majority of the visual excitements of an eye arereceived by the opposite hemisphere. A rather confused notion of these facts has formed itself in the mindsof several critics, and I can discern the proof of this in thelanguage they use. It will be said, for example, that the idea existsin the consciousness or in the mind, and phrases like the followingwill be avoided: "I think with my brain"--the suggestion consists inintroducing an idea in the brain--"The nerve cell perceives andreasons, &c. " Ordinarily these forms of speech are criticised becausethey appear to have the defect of establishing a confusion between twoirreducible elements, the physical and the mental. I think the errorof language proceeds from another cause, since I do not admit thisdistinction between the physical and the mental. I think that theerror consists in supposing vaguely that the consciousnesscomprehends intra-cerebral phenomena, whereas it ignores them. Let me repeat that there is no such thing as intra-cerebralsensibility. The consciousness is absolutely insensitive with regardto the dispositions of the cerebral substance and its mode of work. Itis not the nervous undulation which our consciousness perceives, butthe exciting cause of this wave--that is, the external object. Theconsciousness does not feel that which is quite close to it, but isinformed of that which passes much further off. Nothing that isproduced inside the cranium interests it; it is solely occupied withobjects of which the situation is extra-cranial. It does not penetrateinto the brain, we might say, but spreads itself like a sheet over theperiphery of the body, and thence springs into the midst of theexternal objects. There is, therefore, I do not say a contradiction, but a very strikingcontrast between these two facts. The consciousness is conditioned, kept up, and nourished by the working of the cerebral substance, butknows nothing of what passes in the interior of that substance. Thisconsciousness might itself be compared to a parasitical organism whichplunges its tap roots into the nerve centres, and of which the organsof perception, borne on long stalks, emerge from the cranium andperceive everything outside that cranium. But this is, of course, only a rough image. Strictly, it is possible to explain this distribution of theconscience, singular as it is at first sight, by those reasons ofpractical utility which are so powerful in the history of evolution. A living being has to know the world external to himself in order toadapt and preadapt himself to it, for it is in this outer world thathe finds food, shelter, beings of his own species, and the means ofwork, and it is on this world of objects that he acts in everypossible way by the contractions of his muscles. But with regard tointracephalic actions, they are outside the ordinary sphere of ouractions. There is no daily need to know them, and we can understandthat the consciousness has not found very pressing utilitarian motivesfor development in that direction. One must be an histologist or asurgeon to find an appreciable interest in studying the structure ofthe nerve cell or the topography of the cerebral centres. We can therefore explain well enough, by the general laws ofadaptation, the reason of the absence of what might be called"cerebral sensibility, " but, here as elsewhere, the question of the"Why" is much easier to solve than that of the "How. " The question of the "How" consists in explaining that theconsciousness, directly aroused by a nerve-wave, does not perceivethis undulation, but in its stead the external object. Let us firstnote that between the external object and the nervous influx there isthe relation of cause to effect. It is only the effect which reachesus, our nerve cells, and our consciousness. What must be explained ishow a cognition (if such a word may be employed here) of the effectcan excite the consciousness of the cause. It is clear that the effectdoes not resemble the cause, as quality: the orange I am looking athas no resemblance with the brain wave which at this moment istraversing my optic nerve; but this effect contains everything whichwas in the cause, or, more exactly, all that part of the cause ofwhich we have perception. Since it is only by the intermediary of ournervous system that we perceive the object, all the properties capableof being perceived are communicated to our nervous system andinscribed in the nerve wave. The effect produced therefore is themeasure of our perception of the cause. This is absolutely certain. All bodies possess an infinity of properties which escape ourcognitions; because, as excitants of our organism, these propertiesare wanting in the intensity or the quality necessary to make itvibrate; they have not been tuned in unison with our nervous chords. And, inversely, all we perceive of the mechanical, physical, andchemical properties of a body is contained in the vibration this bodysucceeds in propagating through our cerebral atmosphere. There is inthis a phenomenon of transmission analogous to that which is producedwhen an air of music is sent along a wire; the whole concert heard atthe other extremity of the wire has travelled in the form of delicatevibrations. There must therefore exist, though unperceived by our senses, a sortof kinship between the qualities of the external objects and thevibrations of our nerves. This is sometimes forgotten. The theory ofthe specific energy of the nerves causes it to be overlooked. As wesee that the quality of the sensation depends on the nerve that isexcited, one is inclined to minimise the importance of the excitant. It is relegated to the position of a proximate cause with regard tothe vibration of the nerve, as the striking of a key on the piano isthe proximate cause of the vibration of a string, which always givesthe same degree of sound whether struck by the forefinger or thirdfinger, or by a pencil or any other body. It will be seen at once thatthis comparison is inexact. The specific property of our nerves doesnot prevent our knowing the form of the excitant, and our nerves areonly comparable to piano strings if we grant to these the property ofvibrating differently according to the nature of the bodies whichstrike them. How is it that the nerve wave, if it be the depository of the whole ofthe physical properties perceived in the object, resembles it solittle? It is because--this is my hypothesis--these properties, ifthey are in the undulation, are not there alone. The undulation is thework of two collaborators: it expresses both the nature of the objectwhich provokes it and that of the nervous apparatus which is itsvehicle. It is like the furrow traced in the wax of the phonographwhich expresses the collaboration of an aërial vibration with astylus, a cylinder, and a clock-work movement. This engraved lineresembles, in short, neither the phonographic apparatus nor the aërialvibration, although it results from the combination of the two. Similarly, I suppose that if the nervous vibration resembles so littlethe excitant which gives it birth, it is because the factor nervoussystem adds its effect to the factor external object. Each of thesefactors represents a different property: the external objectrepresents a cognition and the nervous system an excitement. Let us imagine that we succeed in separating these two effects. Itwill be conceived, theoretically, that a separation of this kind willlay bare the hidden resemblances, giving to each collaborator thepart which belongs to it. The excitement, for instance, will besuppressed, and the cognition will be retained. Is it possible tomake, or at least to imagine, such an analysis? Perhaps: for, of thesetwo competing activities, one is variable, since it depends on theconstantly changing nature of the objects which come into relationwith us; the other, on the contrary, is a constant, since it expressesthe contribution of our nerve substance, and, though this last is ofvery unstable composition, it necessarily varies much less than theseries of excitants. We consequently see faintly that these twoelements differ sufficiently in character for us to be able to supposethat they are separable by analysis. But how could this analysis be made? Evidently not by chemical orphysical means: we have no need here of reagents, prisms, centrifugalapparatus, permeable membranes, or anything of that kind. It willsuffice to suppose that it is the consciousness itself that is thedialyser. It acts by virtue of its own laws--that is to say, bychanges in intensity. Supposing that sensibility increases for thevariable elements of the undulation, and becomes insensible for theconstant elements. The effect will be the same as a materialdissociation by chemical analysis: there will be an elimination ofcertain elements and the retention of others. Now, all we know of the consciousness authorises us to entrust thisrôle to it, for it is within the range of its habits. We know thatchange is the law of consciousness, that it is effaced when theexcitements are uniform, and is renewed by their differences or theirnovelty. A continued or too often repeated excitement ceases in timeto be perceived. It is to condense these facts into a formula thatBain speaks of the law of relativity of cognition, and, in spite of afew ambiguities on the part of Spencer and of Bain himself in thedefinition of this law, [50] the formula with the sense I have justindicated is worth preserving. Let us see what becomes of it, when my hypothesis is adopted. Itexplains how certain excitements proceeding from the objects--that isto say, forming part of the variable element--cease to be perceivedwhen they are repeated and tend to become constant. _A fortiori_, itseems to me, should the same law explain how the constant element _parexcellence_, the one which never varies from the first hour, is neverperceived. There is, in the concert of the sounds of nature, anaccompaniment so monotonous that it is no longer perceived; and themelody alone continues to be heard. It is in this precisely that my hypothesis consists. We will suppose anerve current starting from one of the organs of the senses, when itis excited by some object or other, and arriving at the centre of thebrain. This current contains all the properties of the object, itscolour, its form, its size, its thousand details of structure, itsweight, its sonorous qualities, &c. , &c. , properties combined with andconnected by the properties of the nerve-organ in which the current ispropagated. The consciousness remains insensible to those nervousproperties of the current which are so often repeated that they areannulled; it perceives, on the contrary, its variable and accidentalproperties which express the nature of the excitant. By this partialsensibility, the consciousness lays bare that which, in the nervecurrent, represents the object--that is to say, a cognition; and thisoperation is equivalent to a transformation of the current into aperception, image, or idea. There is not, strictly speaking, atransformation, but an analysis; only, the practical result is thesame as that of a transformation, and is obtained without its beingnecessary to suppose the transmutation of a physical into a mentalphenomenon. Let us place ourselves now at the moment when the analysis I amsupposing to be possible has just been effected. Our consciousnessthen assists at the unrolling of representations which correspond tothe outer world. These representations are not, or do not appear tobe, lodged in the brain; and it is not necessary to suppose a specialoperation which, taking them in the brain, should project them to theperiphery of our nerves. This transport would be useless, since forthe consciousness the brain does not exist: the brain, with its fibresand cells, is not felt; it therefore supplies no _datum_ to enable usto judge whether the representation is external or internal withregard to it. In other words, the representation is only localised inrelation to itself; there is no determinate position other than thatof one representation in relation to another. We may therefore rejectas inexact the pretended law of eccentricity of the physiologists, whosuppose that sensation is first perceived as it were centrally, andthen, by an added act, is localised at the peripheric extremity of thenerve. This argument would only be correct if we admitted that thebrain is perceived by the consciousness of the brain. I have alreadysaid that the consciousness is not an anatomist, and that thereforethis problem does not present itself. Such as it is, this hypothesis appears to me to present the advantageof explaining the reason why our consciousness coincides, in certaincircumstances, with the actions of the brain, and, in others, does notcome near them. In other words, it contains an explanation of theunconscious. I can show this by quoting certain exact facts, of whichthe explanation has been hitherto thought to present difficulties, butwhich become very easy to understand on the present hypothesis. Thefirst of these facts relates to the psychology of the motor current. This current has been a great feature in the studies which have beenmade on the feeling of effort and on the physical basis of the will. The motor current is that which, starting from the cerebral cells ofthe motor region, travels by way of the fibres of the pyramidal tractinto the muscles of the body; and it is centrifugal in direction. Researches have been made as to whether we are or may be conscious ofthis current; or rather, the question has been put in somewhatdifferent terms. It has been asked whether a psychological state canbe the counterpart of this motor current, --if, for example, thefeeling of mental effort produced in us at the moment of executing adifficult act or of taking a grave resolution, might not have thismotor current for a basis. The opinion which has prevailed is in the negative. We haverecognised--a good deal on the faith of experiment, and a little alsofor theoretical reasons--that no sensation is awakened by thecentrifugal current. As to the sensation of effort, it has been agreedto place it elsewhere. We put it among the centripetal sensationswhich, are produced as the movement outlines itself, and which proceedfrom the contracted muscles, the stretched ligaments, and thefrictional movements of the articulations. Effort would therefore formpart of all the psychical phenomenology, which is the duplicate ofthose sensory currents which are centripetal in direction. In the long run, I can see no sort of theoretical reason forsubordinating the consciousness to the direction of the nerve current, and for supposing that the consciousness is aroused when this currentis centripetal, and that it cannot follow the centrifugal current. Butthis point matters little. My hypothesis would fairly well explain whythe motor current remains unconscious; it explains the affair bytaking into consideration the nature of this current and not itsdirection. This current is a motor one because it is born in thecentral cells, because it is a discharge from these cells, and is ofentirely nervous origin. Since it does not correspond with theperception of an object--the ever varying object--it is always thesame by nature. It does not carry with it in its monotonous course the_débris_ of an object, as does the sensory current. Thus it can flowwithout consciousness. This same kind of hypothesis supplies us with the reasons why a givensensory current may be, according to circumstances, either consciousor unconscious. The consciousness resulting from the analysis of themolecular wave is, as it were, a supplementary work which may besubsequently added to the realised wave. The propagation of the waveis the essential fact--there is always time to become conscious of itafterwards. It is thus that we happen, in moments of abstraction, toremain insensible to certain even very powerful excitements. Ournervous system registers them, nevertheless, and we can find themagain, later on, within the memory. This is the effect of a belatedanalysis. The converse phenomenon occurs much more frequently. We remark manyactions and perceptions which occur the first time with consciousness, emotion, and effort. Then, when they are repeated, as coordinationbecomes stronger and easier, the reflex consciousness of the operationbecomes feebler. This is the law of habit, which slowly carries ustowards automatism. These observations have even been extended, andthe endeavour made to apply them to the explanation of the origin ofreflex actions and of instincts which have all started withconsciousness. This is a rather bold attempt, for it meets with manyserious difficulties in execution; but the idea seems fairly correct, and is acceptable if we may limit it. It is certain that theconsciousness accompanies the effort towards the untried, and perishesas soon as it is realised. Whence comes this singular dilemmapropounded to it by nature: to create something new or perish? Itreally seems that my hypothesis explains this. Every new act isproduced by nerve currents, which contain many of those variableelements which the consciousness perceives; but, in proportion as theaction of the brain repeats itself and becomes more precise and moreexact, this variable element becomes attenuated, falls to its lowestpitch, and may even disappear in the fixation of habit and instinct. My hypothesis much resembles the system of parallelism. It perfectsit, as it seems to me, as much as the latter has perfectedmaterialism. We indeed admit a kind of parallelism between theconsciousness and the object of cognition; but these two series arenot independent, not simply placed in juxtaposition as is possible inordinary parallelism; they are united and fused together so as tocomplete each other. This new theory appears to me to represent abetter form of the series of attempts which have been inspired by thecommon necessity of making the phenomena of consciousness accord withthe determinism of physical facts. I hold fast to this physical determinism, and accept a strictlymechanical conception of the functions of the nervous system. In myidea, the currents which pass through the cerebral mass follow eachother without interruption, from the sensorial periphery to the motorperiphery; it is they, and they alone, which excite the movements ofthe body by acting on the muscles. Parallelism recognises all thesethings, and I do likewise. Let us now see the advantages of this new system. First, it containsno paralogism, no logical or psychological error, since it does notadvance the supposition that the mental differs by its nature from thephysical phenomenon. We have discussed above the consequences of thiserror, They are here avoided. In the second place, it is explanatory, at least in a certain measure, since the formula we employ allows usto understand, better than by the principle of a simple juxtaposition, why certain nerve currents flow in the light of consciousness, whileothers are plunged into the darkness of unconsciousness. This law ofconsciousness, which Bain called the law of relativity, becomes, whenembodied with my theory of the relations of the physical to the moral, an explanation of the distribution of consciousness through theactions of the brain. I ask myself whether the explanation I have devised ought to beliterally preserved. Perhaps not. I have endeavoured less to present aready-made solution than to indicate the direction in which we oughtto look for one. The law of consciousness which I have used to explainthe transformation of a nerve current into perception and images isonly an empirical law produced by the generalisation of particularobservations. Until now there has been, so far as I know, no attemptto ascertain whether this law of consciousness, notwithstanding thegeneral nature which some authors incline to ascribe to it, might notexplain itself by some more general facts, and might not fit, as aparticular case, into a more comprehensive frame. To be brief, this isvery possible. I have not troubled myself about it, and I have made atranscendental use of this empirical law; for I have impliedlysupposed it to be a first principle, capable of accounting for thedevelopment of the consciousness, but itself incapable of explanation. If other observers discover that that which to me has appearedinexplicable, may be explained by quite peculiar causes, it is clearthat my theory must be abandoned or modified. New theories must thenbe sought for, which will probably consist in recognising differentproperties in the consciousness. A little thought will discoverseveral, I have no doubt. By way of suggestion, I will indicate oneof these hypothetical possibilities: "The consciousness has thefaculty of reading in the effect that which existed in the cause. " Itis not rash to believe that by working out this idea, a certainsolution would be discovered. Moreover, the essential is, I repeat, less to find a solution than to take account of the point whichrequires one; and metaphysics seem to me especially useful when itshows us where the gap in our knowledge exists and what are theconditions required to fill this gap. Above all, I adhere to this idea, which has been one of the guidingforces of this book: there exists at the bottom of all the phenomenaof the intelligence, a duality. To form a true phenomenon, there mustbe at once a consciousness and an object. According to passingtendencies, either of temperament or of fashion, preponderance hasbeen given sometimes to one of the terms of this couple, sometimes tothe other. The idealist declares: "Thought creates the world. " Thematerialist answers: "The matter of the brain creates thought. "Between these two extreme opinions, the one as unjustifiable as theother in the excesses they commit, we take up an intermediateposition. Looking at the balance, we see no argument capable of beingplaced in the scale of the consciousness which may not be neutralisedby an argument placed in the scale of the object; and if we had togive our final verdict we should say: "The consciousness and matterhave equal rights, " thus leaving to every one the power to place, inthis conception of an equality of rights, the hopes of survival ofwhich his heart has need. FOOTNOTES: [Footnote 50: The _équivoque_ perpetrated by BAIN and SPENCER consistsin supposing that the consciousness bears solely on differences. Thisis going too far. I confine myself to admitting that, if sensation isnot changed from time to time, the consciousness becomes weaker anddisappears. ] CHAPTER VI RECAPITULATION I ask permission to reproduce here a communication made by me inDecember 1904 to the Société Française de Philosophie. I there setforth briefly the ideas which I have just developed in this book. Thissuccinct _exposé_ may be useful as a recapitulation of the argument. _Description of Matter. _--The physicists who are seeking for aconception of the Inmost structure of matter in order to explain thevery numerous phenomena they perceive, fancy they can connect themwith other phenomena, less numerous, but of the same order. They thusconsider matter in itself. We psychologists add to matter something more, viz. The observer. Weconsider matter and define it by its relations to our modes ofknowledge--that is to say, by bearing in mind that it is conditionedby our external perception. These are two different points of view. In developing our own standpoint, we note that of the outer world weare acquainted with nothing but our sensations: if we propound thislimit, it is because many observations and experiments show that, between the external object and ourselves, there is but oneintermediary, the nervous system, and that we only perceive themodifications which the external object, acting as an excitant, provokes in this system. Let us provisionally apply to these modifications the term sensations, without settling the question of their physical or mental nature. Other experiments, again, prove to us that our sensations are notnecessarily similar to the objects which excite them; for the qualityof each sensation depends on what is called the specific energy of thenerve excited. Thus, whether the optic nerve be appealed to by a rayof light, an electric current, or a mechanical shock, it always givesthe same answer, and this answer is the sensation of light. It follows that our nervous system itself is only known to us asregards its structure by the intermediary of sensations, and we arenot otherwise more informed upon its nature than upon that of anyother object whatever. In the second place, a much more serious consequence is that all oursensations being equally false, so far as they are copies of theexcitants which provoke them, one has no right to use any of thesesensations to represent to ourselves the inmost structure of matter. The theories to which many physicists still cling, which consist inexplaining all the modalities of matter by different combinations ofmovement, start from false premises. Their error consists inexplaining the whole body of our sensations by certain particularsensations of the eye, of the touch, and of the muscular sense, inwhich analysis discovers the elements and the source of therepresentation of motion. Now these particular sensations have no moreobjective value than those of the tongue, of the nose, and of the ear;in so far as they are related to the external excitant of which it issought to penetrate the inmost nature, one of them is as radicallyfalse as the other. It is true that a certain number of persons will think to escape fromour conclusion, because they do not accept our starting point. Thereexist, in fact, several systems which propound that the outer world isknown to us directly without the intermediary of a _tertium quid_, that is, of sensation. In the first place, the spiritists areconvinced that disembodied souls can remain spectators of terrestriallife, and, consequently, can perceive it without the interposition oforgans. On the other hand, some German authors have recentlymaintained, by rather curious reasoning, that the specific energy ofour nervous system does not transform the excitants, and that oursensations are the faithful copies of that which causes them. Finally, various philosophers, Reid, Hamilton, and, in our own days, the deep and subtle mind of M. Bergson, have proposed to admit that bydirect comprehension we have cognisance of the objects without mysteryand as they are. Let this be admitted. It will change nothing in ourconclusions, and for the following reasons. We have said that no kind of our sensations--neither the visual, thetactile, nor the muscular--permits us to represent to ourselves theinmost structure of matter, because all sensations, without exception, are false, as copies of material objects. We are now assured that weare mistaken, and that our sensations are all true--that is to say, are faithful copies of the objects. If all are true, it comes to thesame thing as if all are false. If all are true, it is impossible tomake any choice among them, to retain only the sensations of sight andtouch, and to use them in the construction of a mechanical theory, tothe exclusion of the others. For it is impossible for us to explainsome by the others. If all are equally true, they all have the sameright to represent the structure of matter, and, as they areirreconcilable, no theory can be formed from their synthesis. Let us, consequently, conclude this: whatever hypothesis may be builtup on the relations possibly existing between matter and oursensations, we are forbidden to make a theory of matter in the termsof our sensations. That is what I think of matter, understood as the inmost structure ofbodies--of unknowable and metaphysical matter. I shall not speak of itagain; and henceforth when I use the word matter, it will be in quitea different acceptation--it will be empirical and physical matter, such as it appears to us in our sensations. It must therefore beunderstood that from this moment we change our ground. We leave theworld of _noumena_ and enter that of phenomena. _Definition of Mind. _--Generally, to define the mind, we oppose theconcept of mind to the concept of matter, with the result that we getextremely vague images in our thoughts. It is preferable to replacethe concepts by facts, and to proceed to an inventory of all mentalphenomena. Now, in the course of this inventory, we perceive that we havecontinually to do with two orders of elements, which are united inreality, but which our thought may consider as isolated. One of theseelements is represented by those states which we designate by the nameof sensations, images, emotions, &c. ; the other element is theconsciousness of these sensations, the cognition of these images, thefact of experiencing these emotions. It is, in other words, a specialactivity of which these states are the object and, as it were, thepoint of application--an activity which consists in perceiving, judging, comparing, understanding, and willing. To make our inventoryorderly, let us deal with these two elements separately and begin withthe first. We will first examine sensation: let us put aside that which is thefact of feeling, and retain that which is felt. Thus defined andslightly condensed, what is sensation? Until now we have employed theword in the very vague sense of a _tertium quid_ interposed betweenthe object and ourselves. Now we have to be more precise, and toinquire whether sensation is a physical or a mental thing. I need nottell you that on this point every possible opinion has been held. Myown opinion is that sensation should be considered as a physicalphenomenon; sensation, be it understood, in the sense of impressionfelt, and not in that of capacity to feel. Here are the arguments I invoke for the support of my thesis: in thefirst place, popular opinion, which identifies matter with what wesee, and with what we touch--that is to say, with sensation. Thispopular opinion represents a primitive attitude, a family possessionwhich we have the right to retain, so long as it is not proved to usto be false: next, this remark, that by its mode of apparition at onceunexpected, the revealer of new cognitions, and independent of ourwill, as well as by its content, sensation sums up for us all weunderstand by matter, physical state, outer world. Colour, form, extent, position in space, are known to us as sensations only. Sensation is not a means of knowing these properties of matter, it isthese properties themselves. What objections can be raised against my conclusion? One has evidentlythe right to apply the term psychological to the whole sensation, taken _en bloc_, and comprising in itself both impression andconsciousness. The result of this terminology will be that, as we knownothing except sensations, the physical will remain unknowable, andthe distinction between the physical and the mental will vanish. Butit will eventually be re-established under other names by utilisingthe distinction I have made between objects of cognition and acts ofcognition;--a distinction which is not verbal, and results fromobservation. What is not permissible is to declare that sensation is apsychological phenomenon, and to oppose this phenomenon to physicalreality, as if this latter could be known to us by any other methodthan sensation. If the opinion I uphold be accepted, if we agree to see in sensation, understood in a certain way, a physical state, it will be easy toextend this interpretation to a whole series of different phenomena. To the images, first, which proceed from sensations, since they arerecurring sensations; to the emotions also, which, according to recenttheories, result from the perception of the movements which areproduced in the heart, the vessels, and the muscles; and finally, toeffort, whether of will or of attention, which is constituted by themuscular sensations perceived, and consequently also results fromcorporeal states. The consequences must be clearly remarked. To admitthat sensation is a physical state, is to admit, by that very fact, that the image, idea, emotion, and effort--all those manifestationsgenerally ascribed to the mind alone--are also physical states. What, then, is the mind? And what share remains to it in all thesephenomena, from which it seems we are endeavouring to oust it? Themind is in that special activity which is engaged in sensation, image, idea, emotion, and effort. For a sensation to be produced; there mustbe, as I said a little time ago, two elements: the something felt--atree, a house, an animal, a titillation, an odour, --and also the factof feeling this something, the consciousness of it, the judgmentpassed on it, the reasoning applied to it--in other terms, thecategories which comprehend it. From this point of view, the dualismcontained in sensation is clearly expressed. Sensation as a thingfelt, that is, the physical part, or matter; sensation as the fact offeeling or of judging, that is, the mind. Mark the language I use. We say that matter is the something felt; butwe do not say for the sake of symmetry, that the mind is the somethingwhich feels. I have used a more cautious, and, I think, a more justformula, which places the mind in the fact of feeling. Let me repeatagain, at the risk of appearing too subtle: the mind is the act ofconsciousness; it is not a subject which has consciousness. For asubject, let it be noted, a subject which feels, is an object ofcognition--it forms part of the other group of elements, the group ofsensations. In practice we represent by mind a fragment of our ownbiography, and by dint of pains we attribute to this fragment thefaculty of having a consciousness; we make it the subject of therelation subject-object. But this fragment, being constituted ofmemories and sensations, does not exactly represent the mind, and doesnot correspond to our definition; it would rather represent the mindsensationalised or materialised. From this follows the curious consequence that the mind is endowedwith an incomplete existence; it is like form, which can only berealised by its application to matter of some kind. One may fancy asensation continuing to exist, to live and to provoke movements, evenafter ceasing to be perceived. Those who are not uncompromisingidealists readily admit this independence of the objects with regardto our consciousness, but the converse is not true. It is impossibleto understand a consciousness existing without an object, a perceptionwithout a sensation to be perceived, an attention without a point ofapplication, an empty wish which should have nothing to wish for; in aword, a spiritual activity acting without matter on which to act, ormore briefly still--mind without matter. Mind and matter arecorrelative terms; and, on this point, I firmly believe that Aristotlewas much closer to the truth than many modern thinkers. I have convinced myself that the definition of mind at which we havejust arrived is, in its exactness and soberness, the only one whichpermits psychology to be distinguished from the sciences nearest toit. You know that it has been discovered in our days that there existsa great difficulty in effecting this delimitation. The definitions ofpsychology hitherto proposed nearly all have the defect of notagreeing with the one thing defined. Time fails us to review them all, but I shall point out one at least, because our discussion on thisparticular formula will serve as a preparation for taking in hand thelast question that remains to be examined--the relation of the mindto the body. According to the definition I am aiming at, psychology would be thescience of internal facts, while the other sciences deal with theexternal. Psychology, it has also been said, has as its instrumentintrospection, while the natural sciences work with the eye, thetouch, the ear--that is to say, with the senses of extrospection. To this distinction, I reply that in all sciences there exist but twothings: sensations and the consciousness which accompanies them. Asensation may belong to the inner or the outer world throughaccidental reasons, without any change in its nature; the sensation ofthe outer world is the social sensation which we share with ourfellows. If the excitant which provokes it is included in our nervoussystem, it is the sensation which becomes individual, hidden to allexcept ourselves, and constituting a microcosm by the side of amacrocosm. What importance can this have, since all the differencedepends on the position occupied by the excitant? But we are persistently told: there are in reality two ways ofarriving at the cognition of objects--from within and from without. These two ways are as opposite as the right and wrong side of a stuff. It is in this sense that psychology is the science of the within andlooks at the wrong side, while the natural sciences reckon, weigh, and measure the right side. And this is so true, they add, that thesame phenomenon absolutely appears under two forms radically differentfrom each other according as they are looked at from one or the otherof the two points of view. Every one of our thoughts, they point outto us, is in correlation with a particular state of our cerebralmatter; our thought is the subjective and mental face, thecorresponding cerebral process is the objective and material face. Though this dualism is frequently presented as an observed truth, Ithink it is possible to show its error. Take an example: I look at theplain before me, and see a flock of sheep pass through it. At the sametime an observer, armed with a microscope _à la_ Jules Verne, looksinto my brain and observes there a certain molecular dance whichaccompanies my visual perception. Thus, on the one hand, is myrepresentation; on the other, a dynamic state of the nerve cells. Thisis what constitutes the right and the wrong sides of the stuff. We aretold, "See how little resemblance there is in this; a representationis a psychical, and a movement of molecules a material, thing. " But I, on the contrary, think there is a great resemblance. When I seethe flock passing, I have a visual perception. The observer who, bythe hypothesis, is at that moment looking into my brain, alsoexperiences a visual perception. Granted, they are not the sameperception. How could they be the same? I am looking at the sheep, heis looking at the interior of my brain; it is not astonishing that, looking at objects so different, we should receive images also verydifferent. But, notwithstanding their difference of object--that is, of content--there are here two visual perceptions composed in the sameway; and I do not see by what right it can be said that one representsa material, the other a physical, phenomenon. In reality, each ofthese perceptions has a two-fold and psycho-physical value--physicalin regard to the object to which it applies, and psychical inasmuch asit is an act of perception, that is to say, of consciousness. For oneis just as much psychical as the other, and as much material, for aflock of sheep is as material a thing as is my brain. If we keep thisconclusion in our minds, when we come to make a critical examinationof certain philosophical systems, we shall easily see the mistake theymake. Spiritualism[51] rests on the conception that the mind can subsist andwork in total independence of any tie to matter. It is true that, indetails, spiritualists make some modification in this absoluteprinciple in order to explain the perceptions of the senses and theexecution of the orders of the will; but the duality, theindependence, and the autonomy of the soul and the body remain, in anycase, the peculiar dogma of the system. This dogma appears to meutterly false; the mind cannot exist without matter to which it isapplied; and to the principle of heterogeneity, so often invoked toforbid all commerce between the two substances, I reply by appealingto intuition, which shows us the consciousness and its differentforms, comparison, judgment, and reasoning, so closely connected withsensation that they cannot be imagined as existing with an isolatedlife. Materialism, we know, argues quite differently; it imagines that aparticular state of the nerve centres has the virtue of generating apsychical phenomenon, which represents, according to variousmetaphors, property, function, effect, and even secretion. Criticshave often asked how, with matter in motion, a phenomenon of thoughtcould be explained or fabricated. It is very probable that those whoadmit this material genesis of thought, represent it to themselvesunder the form of something subtle, like an electric spark, a puff ofwind, a will-of-the-wisp, or an alcoholic flame. Materialists are notalone responsible for these inadequate metaphors, which proceed from ametaphysics constructed of concepts. Let us recollect exactly what apsychical phenomenon is. Let us banish the will-o'-the-wisps, replacethem by a precise instance, and return to the visual perception wetook as an example a little while back: without intending a pun, "revenons à nos moutons. " These sheep which I see in the plain are asmaterial, as real, as the cerebral movement which accompanies myperception. How, then, is it possible that this cerebral movement, aprimary material fact, should engender this secondary material fact, this collection of complicated beings which form a flock? Before going any further, let us invite another philosophical systemto take a place within the circle of our discussion; for the sameanswer will suffice for it as well as for the preceding one, and itwill be as well to deal with both at once. This new system, parallelism, in great favour at the present day, appears to me to be amaterialism perfected especially in the direction of caution. Toescape the mystery of the genesis of the mind from matter, this newsystem places them parallel to each other and side by side, we mightalmost say experimentally, so much do parallelists try to avoidtalking metaphysics. But their position is untenable, and theylikewise are the victims of the mirage of concepts; for they considerthe mental as capable of being parallel to the physical withoutmingling with it, and of subsisting by itself and with a life of itsown. Such a hypothesis is only possible by reason of the insufficientdefinition given to the mind. If it be recognised that the mind has anincomplete existence and is only realised by its incarnation inmatter, the figure which is the basis of parallelism becomesindefensible. There is no longer on the one hand the physical, and onthe other the mental, but on one side the physical and the mentalcombined, and on the other the same combination; which amounts tosaying that the two faces to a reality, which it was thought had beenmade out to be so distinct, are identical. There are not two faces, but one face; and the monism, which certain metaphysicians struggle toarrive at by a mysterious reconciliation of the phenomenal dualitywithin the unity of the noumenon, need not be sought so far afield, since we already discover it in the phenomenon itself. The criticisms I have just pointed out to you, only too briefly, areto be found in several philosophers, confusedly in Berkeley, and withmore precision in M. Bergson's book on _Matière et Mémoire_. Thelatter author, remarking that our brain and the outer world are to usimages of the same order, refuses to admit that the brain, which isonly a very small part of these images, can explain and contain theother and much larger part, which comprises the vast universe. Thiswould amount to saying that the whole is comprised in the part. Ibelieve that this objection is analogous to the one just stated withless ingenuity. It is interesting to see how M. Bergson gets out of the difficultywhich he himself raised. Being unwilling to bring forth from themolecular movement of the brain the representation of the world, or tosuperpose the representation on this movement as in the parallelisthypothesis, he has arrived at a theory, very ingenious but ratherobscure, which consists in placing the image of the world outside thebrain, this latter being reduced to a motor organ which executes theorders of the mind. We thus have four philosophical theories, which, while trying toreconcile mind with matter, give to the representation a differentposition in regard to cerebral action. The spiritualist asserts thecomplete independence of the representation in relation to cerebralmovement; the materialist places it after, the parallelist by the sideof, the cerebral movement; M. Bergson puts it in front. I must confess that the last of these systems, that of M. Bergson, presents many difficulties. As he does not localise the mind in thebody, he is obliged to place our perception--that is to say, a part ofourselves--in the objects perceived; for example, in the stars when weare looking at them. The memory is lodged in distant planes ofconsciousness which are not otherwise defined. We understand withdifficulty these emigrations, these crumblings into morsels of ourmind. This would not matter if our author did not go so far as tomaintain that the sensory nerves of the brain are not sensory nerves, and that the severance of them does not suppress sensations, butsimply the motor efforts of these sensations. All the physiologist inme protests against the rashness of these interpretations. The principal difficulties of the problem of the union between themind and the body proceed from the two following facts, which seemincompatible. On the one hand, our thought is conditioned by a certainintra-cerebral movement of molecules and atoms; and, on the otherhand, this same thought has no consciousness of this molecularmovement. It does not know the path of the wave in our nerves; it doesnot suspect, for example, that the image of the objects is reversed inthe retina, or that the excitements of the right eye for the most partgo into the left hemisphere. In a word, it is no anatomist. It is avery curious thing that our consciousness enters into relation onlywith the extra-cerebral, the external objects, and the superficies ofour bodies. From this, this exact question suggests itself: a molecular wave mustcome as far as our visual cerebral centre for us to have theperception of the object before our eyes; how is it that ourconsciousness is unaware of this physiological event from which itdepends, and is borne towards the distant object as if it sprang forthoutside our nervous system? Let us first remark, that if we do not perceive this wave, yet it mustcontain all we know of the external object, for it is evident that weonly know of it that part of its properties which it transmits to ournerves and our nerve centres. All the known substance of the externalobject is, then, implied in this vibration; it is there, but it is notthere by itself. The vibration is the work of two collaborators; itexpresses at once the nature of the object which provokes it, and thenature of the nerve apparatus which transports it, as the furrowtraced in the wax of the phonograph implies the joint action of anaërial vibration with a stylus, a cylinder, and, a clock-workapparatus. I therefore suppose--and this is, I say it plainly, but anhypothesis--that if the nervous vibration so little resembles theexternal excitant which generates it, it is because the factor nervoussystem superadds its effect to the factor excitant. Let us imagine, now, that we have managed to separate these two effects, and we shallunderstand that then the nervous event so analysed might resemble onlythe object, or only the nervous system. Now, of these two effects, oneis constant, that one which represents the action of the nervoussystem; there is another which varies with each new perception, andeven with every moment of the same perception--that is to say, theobject. It is not impossible to understand that the consciousnessremains deaf to the constant and sensitive to the variable element. There is a law of consciousness which has often been described, andfresh applications of which are met with daily: this is, that theconsciousness only maintains itself by change, whether this changeresults from the exterior by impressions received, or is produced fromthe interior by movements of the attention. Let us here apply thisempirical law, and admit that it contains a first principle. It willthen be possible for us to understand that the consciousness formedinto a dialyser of the undulation may reject that constant elementwhich expresses the contribution of the nervous system, and may laybare the variable element which corresponds to the object: so that anintestinal movement of the cerebral substance, brought to light bythis analytical consciousness, may become the perception of an object. By accepting this hypothesis, we restore to the sensory nerves and tothe encephalic centres their property of being the substrata ofrepresentation, and avoid the objection made above against materialismand parallelism, that they did not explain how a cerebral movement, which is material, can engender the perception of an object whichdiffers greatly from it and is yet as material as the movementitself. There is not here, properly speaking, either generation, transformation, or metamorphosis. The object to be perceived iscontained in the nerve current. It is, as it were, rolled up in it;and it must be made to go forth from the wave to be seen. This last isthe work of the consciousness. FOOTNOTES: [Footnote 51: See [Note 43] on p. 191. ] INDEX ABSTRACTIONS, character of, 8 "Archives de Psychologie, " 198 Aristotle, 106, 129, 169, 186-190, 201, 265 Association, "inseparable, " 116 Automatism, 250 BAIN, 3, 121, 186, 189, 219, 245, 252 Belfast, congress at, 207 Bergson, 47, 86; theory of images and brain, 226-230; refutation of, 230-233; 259, 271, 272 Berkeley, 47, 109, 225, 226, 227, 271 Berthelot, 147 Binet, 3, 191; theory of mind and brain, 236, 255 Body, union with mind, 179; Aristotle on body and soul, 188 Brain, 225, 226, 227; and consciousness, 236, 237, 247 Brieux, 209 Brillouin, 10 CATEGORIES, 106, 107, 114, 190, 263 Change, law of consciousness, 245 Cognition, 15, 33, 58, 98, 105, 107, 117, 123, 140, 141, 145, 153, 155, 157, 162, 184, 190, 195, 208, 225, 228, 241, 243, 246, 251, 260, 262, 264, 266 Comte, Auguste, 213 Concepts, method of, 6, 7; metaphysics of, 8, 223 Conclusion, 234-255 Condillac, 98 Condition, normal, 80 Consciousness, 58, 195; anatomical ignorance of, 237, 238; definition of: relation subject-object, categories of the understanding, separability of the consciousness from its object, idealism, 96-134; as dialyser, 244; law of, 275, 276; and nerve current, 247-255; manifestations of, 236; of a state, 63; origin of, 180; phenomena of, 17, 88, 190, 210, 223; useless luxury, 222 Contiguity, law of, 169, 170, 173 Current, motor, psychology of, 248, 249; nerve, 246, 249, 250, 251, 252, 276; sensory, 250 DANTEC, "Les Lois Naturelles, " 10 Dastre, "La Vie et la Mort, " 10, 145 Democritus, 158 Descartes, 64, 77, 78, 97, 152, 193 "Discours de la Méthode, " 77 Dreams, 82, 87 Dualism, of mind and matter, 69, 71, 182, 140, 155, 182, 254, 263 Duality, of sensation, 78; of ideation, 78; of consciousness and object, 199; of nature, 224; of soul and body, 269 Duhem, evolution of mechanics, 10 Ebbinghaus, 160, 161 Eccentricity, law of, 247 Effort, psychological nature of, 94; sensation of, 249, 263 Ego, 75, 86, 88, 89, 99, 152; and non-ego, 96, 100, 101 Emotions, definitions of the, 88-95, 263 Energy, 30, 31 Enumeration, method of, 6 Epiphenomenon, 222 "Étude Expérimentale de l'Intelligence" (Binet), 8 Excitant, the, 18, 21, 22, 83, 244, 257, 258, 266 Existence or reality, 84, 85 Externospection, 140-146 Fathers of the Church, 201 Fechner, 149 Ferrier, 73 Finality, definition of, 163 Flournoy, 70, 73, 182, 191, 198 Geneva, congress of, philosophy at, 226 Goblot, E. , "La Finalité sans Intelligence, " 164 Habit, law of, 250 Hallucinations, 81, 82, 87 Hamilton, William, 47, 65, 256; "Philosophy" of, 47 Herbart, 90, 91 Herrick, C. L. , 86 Heterogeneity, axiom of, 182, 183; principle of, 8, 73, 74, 182, 183, 194, 205, 206, 208, 215, 269 "Histoire du Matérialisme" (Lange), 137 Hume, 64, 109 Huxley, 118, 222 Idealism, principle of, 64, 73, 119-125; refutation of, 95-200 Ideation, duality of, 78, 80 Identity, 221 Image, definition of the, 76-87, 263 Intellectualism, definition of, 166 Intelligence, only inactive consciousness, 117; materialist explanation of, 204 Inter-actionism, 185 Introspection, 140-146 Intuition, 269 James, William, theory of emotion, 91-94; 100, 163 "Journal of Philosophy, " 100 Kant, 34, 106, 107, 108, 181, 190, 235 Kelvin, Lord, 11 Knowable, the, 4, 5, 7 Knowledge and its object, 55-59; two groups of, 98 Külpe, 160 "L'Ame et le Corps, " 3 "La Finalité sans Intelligence" (Goblot), 164 "La Nouvelle Monadologie" (Renouvier et Prat), 64 "La Philosophie de Hamilton, " 47 "La Vie et la Mort" (Dastre), 10 Ladd, 58 _note_[14] Lange, theory of emotion, 91; "Histoire du Matérialisme, " 137 Law of contiguity, 162 _note_[37], 169, 170, 173 Law of eccentricity, 247 Law of mental expression rejected, 162 _note_[37]; mental distinguished from physical, 163 Law, psychological compared with natural, 167, 168 Law of relativity of cognition, 245 Law of similarity, 162 _note_[37], 169, 170 Le Bon, Gustave ("l'Evolution de la Matière"), 27 "Le Paralogisme psycho-physiologique" (Bergson), 226 "Le Personnellisme" (Renouvier), 226 "Leçons de Philosophie" (Rabier), 148 Leibnitz, 129, 195, 220 Littré, 207 Locke, 139 "Logical and Psychological Distinction between the True and the Real" (Herrick), 86 Lotze, 73, 148 Lyons, 66 Mach, 160 Materialism, origin and definition of, 201-203; refutation of, 203-214; 269, 275 "Matière et Mémoire" (Bergson), 86, 226, 229, 230, 271 Matter, definition of, 3-51; description of, 256-260; distinct from mind, 3; domain of physics, 6; mechanical theories of, 27-43; non-significant properties of, 172, 173; _X_ of; 18, 21, 25, 49 Mechanics, fetichism of, 220 Mechanism, nervous, to imitate intellectual act, 221 Metaphysics, 128 _note_[31], 234, 235 "Métaphysique et Psychologie" (Flournoy), 182 Method, rule of, 5; of concepts and enumeration, 6 Meudon, 152 Mill, John Stuart, 13, 19, 47, 64, 116, 121 Mind, definition of, 55-175; 260-266; distinction between, and matter, 3; domain of psychology, 6; incomplete life of, 179-190; inseparability of, and matter, 185; inventory of 56; "Mind and Body" (Bain), 3, 219 Monadism, 195 Monism, 69, 271 Motion, 35 Movement, molecular, 73; vibratory, 31 Müller, 21 Münsterberg, 160 Nerves, motor, 228, 230; power of distinction, 22; specific energy of, 21, 46, 242; sensory, 228, 230, 232, 273, 275; vibrations of, 242, 243; nervous system, 16, 17, 24, 25, 44, 45, 48, 115, 228, 241, 257, 258, 274, 275 Noumena, 34, 35, 43, 109, 142 _note_[34], 260, 271 Object. See _Subject_ Observation, 235 Organ, function of, material, 206 Ostwald, 10 Panmaterialism, 70 Panpsychism, 70, 195, 198 Parallelism, definition of, 214-220; refutation of, 221-224; 251; 252, 270-272; 275 Parallelist theory, 132 Perceptible, the, 84, 85 Perception, intermediate character of, 15; of a child, 232 Personality, formation of, 100 Phenomena, auditory, 37; physical, 30, 31; visual, 37 Phenomenism of Berkeley, 109 _note_[26] "Philosophical Review, " 70 Philosophy, history of, 200 "Philosophy of Hamilton" (J. S. Mill), 47 Pilon, 113 Plato, 201 Preadaptation, process of, 164-175 Prince, Morton, 70 Probabilism forced upon us, 174 "Psychical Review, " 86 "Psychologie, " 112 "Psychologie du Raisonnement" (Binet), 113 Psychology, definitions of, 135-175, 265, 266 Rabier, E. , 98, 112, 148 Radio-activity, 27 Reason developed according to law, 169 Recapitulation, 256-276 Reid, Thomas, 47, 65, 259 Relativity, principle of, 104, 109, 252 Renouvier, 64, 97, 106, 205, 226 "Revue Générale des Sciences, " 10 "Revue de Métaphysique et de Morale, " 164, 226 "Revue de Philosophie, " 10 Raymond, Du Bois, 73 Ribot, 137 Search, direction of, 5, 6 Sensation, 10, 14, 35, 44, 50, 51, 55; definition of, 60-75; mistrusted by physicists, 28-30; only means of acquaintance with outer world, 10-26, 50, 256-259; physical or mental, 261-266; visual, 73 Sensibility, cerebral, 239, 240; employment in physiology, 61 Separation of consciousness from its object, 126-134 Similarity. See _Law_ Simon, Dr. , 209 Société Française de Philosophie, 256 Soul, distinct from body, 77; union of body and, 179-276 Souls, disembodied, 45 Specificity of Nerves. See _Nerves_ Spencer, Herbert, 245 Spiritualism, refutation of, 192, 195, 268, 269 Strong, M. , 195 Subject, defined and distinguished from object, 96 Substance, definition of, 102 Substantialism, 134 Symbols, mechanical theories of matter, 27-43 System, nervous, 16, 17, 24, 25, 44, 45, 48, 115, 228, 241, 257, 258, 274, 275 Taine, 79 Theories, modern, 225-233 Thought, not a movement, 7, 8; characteristics of, 76 Truth, 84, 85 Tyndall, 89, 207 Unconsciousness, 127-133 Understanding, categories of the, 103-118 Unknowable, the, 25, 26 Union of mind and body, problem of, 273; of soul and body, 179-276 Verne, Jules, 267 Vogt, Karl, 204 Wave, molecular, 273, 274, 276; nerve, 243 Will, the most characteristic psychical function, 166, 167 World, assembly of sensations, 26; our ideas, 65; external known only by our sensations, 10-26; 50, 256-259 _X_ of matter, 18, 21, 25, 49 Zoologist, visual sensations of, 13 * * * * * THE INTERNATIONAL SCIENTIFIC SERIES. Each Book Complete in One Volume. 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