This book affirms the realty of spirit and the reality of matter and tries to determine the relation of the one to the other by the study of a definite example, that of memory. It is, then, frankly dualistic. But, on the other hand, it deals with body and mind in such a way as, we hope, to lessen greatly, if not to overcome, the theoretical difficulties which have always beset dualism, and which cause it, though suggested by the immediate verdict of consciousness and adopted by common sense, to be held in small honor among philosophers.
These difficulties are due, for the most part, to the conception, now realistic, now idealistic, which philosophers have of matter. The aim of our first chapter is to show that realism and idealism both go too far, that it is a mistake to reduce matter to the perception which we have of it, a mistake also to make of it a thing able to produce in us perceptions, but in itself of another nature than they. Matter, in our view, is an aggregate of “images.” And by “image” we mean a certain existence which is more than that which the idealist calls a representation, but less than that which the realist calls a thing – an existence placed halfway between the “thing” and the “representation.” This conception of matter is simply that of common sense. It would greatly astonish a man unaware of the speculations of philosophy if we told him that the object before him, which he sees and touches, exists only in his mind and for his mind or even, more generally, exists only for mind, as Berkeley held. Such a man would always maintain that the object exists independently of the consciousness which perceives it. But, on the other hand, we should astonish him quite as much by telling him that the object is entirely different from that which is perceived in it, that it has neither the color ascribed to it by the eye nor the resistance found in it by the hand. The color, the resistance, are, for him, in the object: they are not states of our mind; they are part and parcel of an existence really independent of our own. For common sense, then, the object exists in itself, and, on the other hand, the object is, in itself, pictorial, as we perceive it: image it is, but a self-existing image.
This is just the sense in which we use the word image in our first chapter. We place ourselves at the point of view of a mind unaware of the disputes between philosophers. Such a mind would naturally believe that matter exists just as it is perceived; and, since it is perceived as an image, the mind would make of it, in itself, an image. In a word, we consider matter before the dissociation which idealism and realism have brought about between its existence and its appearance. No doubt it has become difficult to avoid this dissociation now that philosophers have made it. To forget it, however, is what we ask of the reader. If, in the course of this first chapter, objections arise in his mind against any of the views that we put forward, let him ask himself whether these objections do not imply his return to one or the other of the two points of view above which we urge him to rise.
Philosophy made a great step forward on the day when Berkeley proved, as against the “mechanical philosophers,” that the secondary qualities of matter have at least as much reality as the primary qualities. His mistake lay in believing that, for this, it was necessary to place matter within the mind and make it into a pure idea. Descartes, no doubt, had put matter too far from us when he made it one with geometrical extensity. But, in order to bring it nearer to us, there was no need to go to the point of making it one with our own mind. Because he did go as far as this, Berkeley was unable to account for the success of physics, and, whereas Descartes had set up the mathematical relations between phenomena as their very essence, he was obliged to regard the mathematical order of the universe as a mere accident. So the Kantian criticism became necessary, to show the reason of this mathematical order and to give back to our physics a solid foundation – a task in which, however, it succeeded only by limiting the range and value of our senses and of our understanding. The criticism of Kant, on this point at least, would have been unnecessary; the human mind, in this direction at least, would not have been led to limit its own range; metaphysics would not have been sacrificed to physics, if philosophy had been content to leave matter half way between the place to which Descartes had driven it and that to which Berkeley drew it back – to leave it, in fact, where it is seen by common sense.
There we shall try to see it ourselves. Our first chapter defines this way of looking at matter; the last sets forth the consequences of such a view. But, as we said before, we treat of matter only in so far as it concerns the problem dealt with in our second and third chapters, that which is the subject of this essay: the problem of the relation between soul and body.
This relation, though it has been a favorite theme throughout the history of philosophy, has really been very little studied. If we leave on one side the theories which are content to state the “union of soul and body” as an irreducible and inexplicable fact, and those which speak vaguely of the body as an instrument of the soul, there remains hardly any other conception of the psychophysiological relation than the hypothesis of “epiphenomenalism” or that of “parallelism,” which in practice – I mean in the interpretation of particular facts – both end in the same conclusion. For whether, indeed, thought is regarded as a mere function of the brain and the state of consciousness as an epiphenomenon of the state of the brain, or whether mental states and brain states are held to be two versions, in two different languages, of one and the same original, in either case it is laid down that, could we penetrate into the inside of a brain at work and behold the dance of the atoms which make up the cortex, and if, on the other hand, we possessed the key to psychophysiology, we should know every detail of what is going on in the corresponding consciousness.
This, indeed, is what is most commonly maintained by philosophers as well as by men of science. Yet it would be well to ask whether the facts, when examined without any preconceived idea, really suggest an hypothesis of this kind. that there is a close connection between a state of consciousness and the brain we do not dispute. But there is also a close connection between a coat and the nail on which it hangs, for, if the nail is pulled out, the coat falls to the ground. Shall we say, then, that the shape of the nail gives us the shape of the coat, or in any way correspond to it? No more are we entitled to conclude, that there is any parallelism between the two series psychical and physiological. When philosophy pleads that the theory of parallelism is born out of the results of positive science, it enters upon an unmistakably vicious circle; for, if science interprets connection, which is a fact, as signifying parallelism, which is an hypothesis (and an hypothesis to which it is difficult to attach an intelligible meaning), it does so, consciously or unconsciously, for reasons of a philosophical order: it is because science has been accustomed by a certain type of philosophy to believe that there is no hypothesis more probable, more in accordance with the interests of scientific inquiry.
Now, as soon as we do, indeed, apply to positive facts for such information as my help us to solve the problem, we find it is with memory that we have to deal. This was be expected, because memory – we shall try to prove in the course of this work – is just the intersection of mind and matter. But we may leave out the reason here: no one, at any rate, will deny that, among all the facts capable of throwing light on the psychophysiological relation, those which concern memory, whether in the normal or in the pathological state, hold a privileged position. Not only is the evidence here extremely abundant (consider the enormous mass of observations collected in regard to the various kinds of aphasia), but nowhere else have anatomy, physiology and psychology been able to lend each other such valuable aid. Anyone who approaches, without preconceived ideas and on the firm ground of facts, the classical problem of the relations of soul and body, will soon see this problem as centering upon the subject of memory, and, even more particularly, upon the memory of words: it is from this quarter, undoubtedly, that will come the light which will illumine the obscurer parts of the problem.
The reader will see how we try to solve it. Speaking generally, the physical state seems to us to be, in most cases, immensely wider than the cerebral state, I mean that the brain state indicates only a very small part of the mental state, that part which is capable of translating itself into movements and locomotion. Take a complex thought which unrolls itself in a chain of abstract reasoning. This thought is accompanied by images, that are at least nascent(freshly generated in a reactive form). And these images themselves are not pictured in consciousness without some foreshadowing, in the form of a sketch or a tendency, of the movements by which these images would be acted or played in space – would, that is to say, impress particular attitudes upon the body, and set free all that they implicitly contain of spatial movement. Now, of all the thought which is unrolling, this, in our view, is what the cerebral state indicates at every moment. he who could penetrate into the interior of a brain and see what happens there, would probably obtain full details of these sketched-out, or prepared, movements; there is no proof that he would learn anything else. Were he endowed with a superhuman intellect, did he possess the key to psychophysiology, he would know no more of what is going on in the corresponding consciousness than we should know of a play from the comings and goings of the actors upon the stage.
That is to say, the relation of the mental to the cerebral is not a constant, any more than it is simple, relation. According to the nature of the play that is being acted, the movements of the players tell us more or less about it: nearly everything, if it is a pantomime; next to nothing, if it is a delicate comedy. Thus our cerebral state contains more or less of our mental state in the measure that we reel off our psychic life into action or wind it up into pure knowledge.
There are then, in short, divers tones of mental life, or, in other words, our psychic life may be lived at different heights, now nearer to action, now further removed from it, according to the degree of our attention to life. Here we have one of the ruling ideas of this book – the idea, indeed, which served as the starting point of our inquiry. That which is usually held to be a greater complexity of the psychical state appears to us, from our point of view, to be a greater dilatation of the whole personality, which, normally narrowed down by action, expands with the unscrewing of the vice in which it has allowed itself to be squeezed, and, always whole and undivided, spreads itself over a wider and wider surface. That which is commonly held to be a disturbance of the psychic life itself, an inward disorder, a disease of the personality, appears to us, from our point of view, to be an unloosing or a braking of the tie which binds this psychic life to its motor accompaniment, a weakening or an impairing of our attention to outward life. This opinion, as also that which denies the localization of the memory-images of words and explains aphasia quite otherwise than by such localization, was considered paradoxical at the date of the first publication of the present work (1896). It will appear much less so now. The conception of aphasia then classical, universally admitted, believed to be unshakable, has been considerably shaken in the last few years, chiefly by reasons of an anatomical order, but partly also by reasons of the same kind as those which we then advance. And the profound and original study of neuroses made by Professor Pierre Janet has led him, of late years, to explain all psychasthenic forms of disease by these same considerations of psychic “tension” and of attention to reality which were then presumed to be metaphysical.
In truth, it was not altogether a mistake to call them by that name. Without denying to psychology, any more than to metaphysics, the right to make itself into an independent science, we believe that each of these two sciences should set problems to the other and can, in a measure, help it to solve them. How should it be otherwise, if psychology has for its object the study of the human mind working for practical utility, and if metaphysics is but this same mind striving to transcend the conditions of useful action and to come back to itself as to a pure creative energy? Many problems, which appear foreign to each other as long as we are bound by the letter of the terms in which these two sciences state them, are seen to be very near akin, and to be able to solve each other when we thus penetrate into their inner meaning. We little thought, at the beginning of our inquiry, that there could be any connection between the analytical study of memory and the question, which is debated between realists and idealists or between mechanists and dynamists, with regard to the existence or the essence of matter. Yet this connection is real, it is even intimate; and, if we take it into account, a cardinal metaphysical problem is carried into the open field of observation, where it may be solved progressively, instead of forever giving rise to fresh disputes of the schools within the closed lists of pure dialectic. The complexity of some parts of the present work is due to the inevitable dovetailing of problems which results from approaching philosophy in such a way. But through this complexity, which is due to the complexity of reality itself, we believe that the reader will find his way if he keeps a fast hold on the two principles which we have used as a clue throughout our own researches. The first is that in psychological analysis we must never forget the utilitarian character of our mental functions, which are essential turned toward action. The second is that the habits formed in action find their way up to the sphere of speculation, where they create fictitious problems, and that metaphysics must begin by dispersing this artificial obscurity.
Paris, October 1910