INTRODUCTION

       Table of Contents

      THIS book affirms the reality 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 honour 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 half-way 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 colour ascribed to it by the eye, nor the resistance found in it by the hand. The colour, 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 favourite 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 'parallelisms' which in practice — I mean in the interpretation of particular facts — both end in the same conclusions. For whether, indeed, thought is regarded as a mere function