The Mind and the Brain

Flournoy has somewhere written that the chief interest of the systems of metaphysics lies less in the intellectual constructions they raise than in the aspirations of the mind and of the heart to which they correspond. Without taking literally this terribly sceptical opinion, it would be highly useful to begin the study of any metaphysical system by the psychology of its author. The value of each system would be better understood, and their reasons would be comprehended.

This book is too short to permit us to enter into such biographical details. I am obliged to take the metaphysical systems en bloc, as if they were anonymous works, and to efface all the shades, occasionally so curious, that the thought of each author has introduced into them. Yet, however brief our statement, it seems indispensable to indicate clearly the physical or moral idea concealed within each system.

Spiritualism

It is known that spiritualism is a doctrine which has for its chief aim the raising of the dignity of man, by recognising in him faculties superior to the properties of matter. We constantly meet, in spiritualism, with the notion of superior and inferior, understood not only 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 ideas of his habitual adversary, the materialist; he finds them not only false, but dangerous, and is indignant with them; some persons even ingenuously acknowledge that they hold firmly to certain principles because they fear to be converted to materialism. I can also discern in this system a very natural horror of death, which inspires in so many people, of whom I am one, both hatred and disgust. The spiritualist revolts against the prospect of a definitive annihilation of thought, and the system he adopts is largely explained as an effort towards immortality.

This effort has led to the theory of two substances, the soul and the body, which are represented as being as thoroughly separated as possible. The soul has not its origin in the body, and it derives none of its properties from its fellow; it is a substance created in complete independence relatively to the body; the soul, in its essence, has nothing in common with matter. The essence of the soul, said Descartes, is thought; the essence of the body is extent. It follows from this that the soul, in its determinations and actions, is liberated from the laws and necessities of the corporeal nature; it is a free power, a power of indetermination, capable of choice, capable of introducing new, unforeseen, and unforeseeable actions, and on this point opposes itself to corporeal phenomena, which are all subject to a determinism so rigorous that any event could be foreseen if its antecedents were known. Another consequence of spiritualism is the admission of the immortality of the soul, which, being widely distinct from the body, is not affected by its dissolution; it is, on the contrary, liberated, since death cuts the link which binds them together.

But there is a link, and the explanation of this link brings with it the ruin of the whole system. One is forced to admit that this principle of the separation of body and soul is liable, in fact, to many exceptions. Even if they are two isolated powers, the necessities of life oblige them to enter continually into communication with each other. In the case of perceptions, it is the body which acts on the soul and imparts sensations to it; in movements, it is the soul, on the contrary, which acts on the body, to make it execute its desires and its will.

Spiritualists must acknowledge that they are at some trouble to explain this traffic between the two substances; for, with their respect for the principle of heterogeneity mentioned above, they do not manage to conceive how that contact of the physical and the mental can be made which is constantly necessary in the life of relation. By what means, have they long asked themselves, can that which is only extent act on that which is only thought? How can we represent to ourselves this local union of matter with an immaterial principle, which, by its essence, does not exist in space? The two substances have been so completely separated, to insure the liberty of the soul and its superiority over the body, that it has become impossible to bring them together. The scission has been too complete. They cannot be sewn together again.

Such are the principal objections raised against spiritualism. These objections are derived from points of view which are not ours, and we have therefore no need to estimate their value.

From our point of view, the spiritualist conception has chosen an excellent starting point. By establishing the consciousness and the object of cognition as two autonomous powers, neither of which is the slave of the other, spiritualism has arrived at an opinion of irreproachable exactness; it is indeed thus that the relations of these two terms must be stated; each has the same importance and the right to the same autonomy.[44 - I do not insist on the difference between my conception and the spiritualistic conception; my distinction between consciousness and matter does not correspond, it is evident, to that of "facts of consciousness" and "physical facts" which spiritualism sets up.]

Yet, spiritualism has not rested there, and, by a lamentable exaggeration, it has thought that the consciousness, which it calls the soul, could exercise its functions in complete independence of the object of cognition, which it calls matter. There is the error. It consists in misunderstanding the incomplete and, as it were, virtual existence of the consciousness. This refutation is enough as regards spiritualism. Nothing more need be added.

Idealism

Idealism is an exceedingly complex system, varying much with varying authors, very polymorphous, and consequently very difficult to discuss.

The ancient hylozoism, the monadism of Leibnitz, and the recent panpsychism of M. Strong are only different forms of the same doctrine.

Like spiritualism, with which it is connected by many ties, idealism is a philosophy which expresses some disdain for matter, but the thoughts which have sought to shelter themselves under this philosophy are so varied that it would be perilous to try to define them briefly.

There can be discussed in idealism a certain number of affirmations which form the basis of the system. None of these affirmations is, strictly speaking, demonstrated or demonstrable; but they offer very different degrees of probability, and it is for this reason that we shall notice them.

Amongst these affirmations there are some that we have already met with in our study of the definition of sensation; others will be newer to us.

1. Here is one which seems to arise directly from the facts, and appears for a long time to have constituted an impregnable position for idealists. It may be expressed in three words: esse est percipi.

Starting with the observation that every time we bear witness to the existence of the external world, it is because we perceive it, idealists admit that the existence of this external world shares exactly the lot of our perception, and that like it it is discontinuous and intermittent. When we close our eyes, it ceases to exist, like a torch which is extinguished, and lights up again when we open them. We have already discussed this proposition, and have shown that it contains nothing imperative; and we may very well decline to subscribe to it.

2. There follows a second proposition, barely distinct from the previous one. There should be nothing else in objects but that which we perceive, and that of which we have consciousness should be, in the fullest possible acceptation of the words, the measure of what is. Consequently there should be no need to seek, under the object perceived, another and larger reality, a source from which might flow wider knowledge than that we at present possess. This is as disputable as the preceding affirmation, and for the same reasons.

3. The third proposition is the heart of the idealist thesis. It is sometimes presented as a deduction from the foregoing, but it is nevertheless thoroughly distinct from it, and the preceding affirmations might legitimately be accepted and this new one rejected. This proposition may be expressed thus: Everything that is perceived is psychical.

It is not only idealists who subscribe to this opinion, however, and we have seen, when dealing with the definition of matter, that it is widely spread. We understand by it that the objects we perceive exist in the consciousness, are of the consciousness, and are constituted by ideas; the whole world is nothing but idea and representation; and, since our mind is taken to be of a psychical nature, the result is that everything, absolutely everything, the person who knows and the thing known, are all psychical. This is panpsychism. Flournoy, on this point, says, with a charm coloured by irony: "We henceforth experience a sweet family feeling, we find ourselves, so to speak, at home in the midst of this universe …"[45 - Archives de Psychologie, vol. iv. No. 14, Nov. 1904, p. 132 (article on Panpsychism).] We have demonstrated above that the unity here attained is purely verbal, since we cannot succeed in suppressing the essential differences of things.

4. Now comes an affirmation on the genesis of things. After having admitted that the object is an idea of the mind, one of its manifestations, or one of its moods, the idealists go so far as to say that the consciousness is the generating power of ideas, and, consequently, the generating cause of the universe. It is thought which creates the world. That is the final conclusion.

I indicated, beforehand, in the chapters on the definition of sensation and on the distinction between the consciousness and the object, the reasons which lead me to reject the premises of idealism. It will be sufficient to offer here a criticism on its last conclusion: "It is the mind that creates the world."

This thesis strikes at the duality—consciousness and object; it gives the supremacy to the consciousness by making of the object an effect or property of the former. We can object that this genesis cannot be clearly represented, and that for the very simple reason that it is impossible to clearly accept "mind" as a separate entity and distinct from matter. It is easy to affirm this separation, thanks to the psittacism of the words, which are here used like counterfeit coin, but we cannot represent it to ourselves, for it corresponds to nothing. The consciousness constitutes all that is mental in the world; nothing else can be described as mental. Now this consciousness only exists as an act; it is, in other terms, an incomplete form of existence, which does not exist apart from its object, of which the true name is matter. It is therefore very difficult to understand this affirmation, "It is the mind that creates the world," since to be able to do so, we should have to imagine a consciousness without an object.

Moreover, should we even succeed in doing so, we should be none the more disposed, on that account, to give assent to this proposition. Consciousness and matter represent to us the most different and antithetical terms of the whole of the knowable. Were the hypothesis to be advanced that one of these elements is capable of engendering the other, we should immediately have to ask ourselves why this generating power and this pre-eminence should be attributed to one rather than to the other element. Who can claim that one solution is more clear, more reasonable, or more probable than the other?

One of the great advantages of the history of philosophy here asserts itself. This history shows us that different minds when reflecting on the same problems have come to conceive solutions which have appeared to them clear, and consequently were possible; now, as these solutions are often contradictory, nothing shows better than their collation the distance 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 diametrically opposed to that of the idealists. It may be said that these two conceptions, opposed in sense, annul each other, and that each of these two philosophical systems has rendered us service by demonstrating the error of the opposing system.

CHAPTER III

MATERIALISM AND PARALLELISM

Materialism

Materialism is a very ancient doctrine. It is even the most ancient of all, which simply proves that amongst the different explanations given of our double physico-mental nature, this doctrine is the easiest to understand. The origin of materialism is to be found in the beliefs of savage tribes, and is again found, very clearly defined, in the philosophy of those ancient Greeks who philosophized before Plato and Aristotle. A still stranger fact is that the thoughts of a great number of the Fathers of the Church inclined towards the philosophy of matter. Then, in the course of its evolution, there occurred a moment of eclipse, and materialism ceased to attract attention till the contemporary period in which we assist at its re-birth, Nowadays, it constitutes a powerful doctrine, the more so that it has surreptitiously crept into the thoughts of many learned men without their being clearly conscious of it. There are many physicists and physiologists who think and speak as materialists, though they have made up their minds to remain on the battle-ground of observed facts and have a holy horror of metaphysics. In a certain sense, it may be said that materialism is the metaphysics of those who refuse to be metaphysicians.

It is very evident that in the course of its long history, materialism has often changed its skin. Like all knowledge, it has been subject to the law of progress; and, certainly, it would not have been of a nature to satisfy the intellectual wants of contemporary scholars, had it not stripped itself of the rude form under which it first manifested itself in the mind of primitive man. Yet what has enabled the doctrine to keep its unity through all its changes is that it manifests a deeply human tendency to cling by preference to everything visible and tangible.

Whatever strikes the eyes, or can be felt by the hand, seems to us in the highest degree endowed with reality or existence. It is only much later, after an effort of refined thought, that we come to recognise an existence in everything that can be perceived in any way whatever, even in an idea. It is still later that we understand that existence is not only that which is perceived but also that which is linked logically with the rest of our knowledge. A good deal of progress has been necessary to reach this point.

As I have not the slightest intention of giving even an abridged history of materialism, let us come at once to the present day, and endeavour to say in what consists the scientific form this doctrine has assumed. Its fundamental basis has not changed. It still rests on our 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, the visual, the tactile, and the muscular.

The extraordinary development of the physical sciences has no doubt given an enormous encouragement to materialism, and it may be said that in the philosophy of nature it occupies a principal place, and that it is there in its own domain and unassailable.

It has become the expression of the idea that everything that can be explained scientifically, everything susceptible of being measured, is a material phenomenon. It is the representation of the material explanation pushed to its last limits, and all experiments, all calculations, all inductions resting on the grand principle of the conservation of matter and energy plead in its favour.

We will examine with some precision how far such a doctrine solves the problem 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 its explanation, it has transported into the domain of thought the idea of function, and it has supposed that the soul is to the body in the relation of function to organ. Intelligence would thus be a cerebral function. To explain intelligence, materialists link it with matter, turn it into a property of matter, and compare it to a movement of matter, and sometimes even to a secretion. So Karl Vogt, the illustrious Genevan naturalist, one day declared, to the great scandal of every one, that the brain secretes the thought as the kidney does urine. This bold comparison seemed shocking, puerile, and false, for a secretion is a material thing while thought is not. Karl Vogt also employed another comparison: the brain produces the thought as the muscle produces movement, and it at once seems less offensive to compare the thought to a movement than to compare it to a liquid secretion. At the present day, an illustration still more vague would be used, such as that of a transformation of energy: chemical energy disengaged by the nerve centres would be thus looked upon as transformed into psychical energy.

However, it matters little what metaphors are applied to for help in explaining the passage from the physical to the mental. What characterises materialist philosophy is its belief in the possibility of such a passage, and its considering it as the genesis of thought. "One calls materialist," says Renouvier, with great exactness, "every philosophy which defines thought as the product of a compound whose elements do not imply thought." A sweeping formula which allows us to foresee all the future avatars of the materialist doctrine, and to class 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 will not dwell long on this, but simply recollect that, according to this principle, it is impossible to attribute to the brain the capacity of generating consciousness. Physical force can indeed generate physical force under the same or a different form, and it thus produces all the effects which are determined by the laws of nature. But it is impossible to comprehend how physical force can enrich itself at a given moment by a conscious force. Physical force is reduced to movements of bodies and to displacements of atoms; how could a change of position in any inert objects give rise to a judgment, a reasoning, or any phenomenon of the consciousness? It is further said: this idea of function, which materialists here introduce to render more comprehensible the passage from a material body to a spiritual action, contains only an empty explanation, for the function is not essentially distinct by its nature from the organ; it is simply "the organ in activity," it adds to the organ taken in a state of repose but one change, viz. activity, that is to say movement, and, consequently, the function of an organ is material by the same right as the organ. When a muscle contracts, this contraction, which is the proper function of the muscular fibre, consists in a condensation of the muscular protoplasm, and this condensation is a material fact. When a gland enters into activity, a certain quantity of liquid flows into the channels of the gland, and this liquid is caused by a physical and chemical modification of the cellular protoplasm; it is a melting, or a liquefaction, which likewise is material. The function of the nerve cell is to produce movement, or to preserve it, or to direct it; ii is material like the cells. There is therefore nothing in all those functional phenomena which might lead us to understand how a material cause should be capable of engendering a conscious effect.

It seems that all materialists have acknowledged that here is the vulnerable point in their theory, for it is the principle of heterogeneity which they have especially combated. But their defence is wanting in frankness, and principally consists in subterfuges.

In brief, it affirms that we are surrounded with mystery, that we are not sufficiently learned to have the right to impose limits to the power of matter, and to say to it: "Thou shalt not produce this phenomenon." A materialist theologian declares that he sees no impossibility in stones thinking and arguing, if God, in His infinite power, has decided to unite thought with brute matter. This argument is not really serious; it demands the intervention of so powerful a Deus ex machina, that it can be applied equally to all problems; to solve all is to solve none.

Modern materialists rightly do not bring God into the question. Their mode of argument takes another form; but it remains to be seen if, at bottom, it is not the same as the other. It simply consists in affirming that up till now we know certain properties of matter only, but that science every day discovers new ones; that matter is a reservoir of unknown forces, and that it is not impossible that the origin of psychical forces may yet be discovered in matter. This idea is clearly hinted at by Littré. The physicist Tyndall gave it a definite formula when he uttered at the Belfast Congress this phrase so often quoted: "If I look back on the limits of experimental science, I can discern in the bosom of that matter (which, in our ignorance, while at the same time professing our respect for its Creator, we have, till now, treated with opprobrium) the promise and the power of all forms and qualities of life."

The opponents of the doctrine have not ceased to answer that the matter of to-morrow, like the matter of to-day, can generate none but material effects, and that a difficulty is not solved by putting off its solution to some indefinite date in our scientific evolution: and it certainly seems that the counter-stroke is decisive, if we admit the principle of heterogeneity with its natural consequence.

We will now criticise the above doctrine by making use of the ideas I have above enunciated. The criticism we have to apply to materialism is not the same as that just summarised. The axis of the discussion changes its position.

In the first place, I reproach materialism with presenting itself as a theory of the generation of the consciousness by the object. We have already reproached idealism with putting itself forward as a theory of the generation of the object by the consciousness. The error of the two systems is produced in a converse direction, but is of the same gravity. The consciousness and its object, we say yet again, constitute the widest division it is possible to effect in the domain of cognition; it is quite as illegitimate to reduce the first term to the second as to reduce the second to the first. To reduce one to the other, by way of affiliation or otherwise, there must first be discovered, then, an identity of nature which does not exist.

In the second place, when one examines closely the explanation materialism has imagined in order to derive thought from an action of matter, it is seen that this representation is rendered completely impossible by all we know of the nature of thought. For the materialist to suppose for one moment that thought is a cerebral function, he must evidently make an illusion for himself as to what thought is, and must juggle with concepts. Perhaps, could we penetrate into his own inmost thought, we should discover that at the moment he supposes a mere cell can manufacture the phenomena of consciousness, some vague image suggests itself to him whereby he identifies these phenomena with a light and subtle principle escaping from the nerve cell, something which resembles an electric effluve, or a will-of-the-wisp, or the flame from a punch-bowl.[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 issuing from brain in the form of an electric gleam." Dr. Simon also informed me, during the reading of my manuscript, that he saw "thought floating over the brain like an ignis fatuus."]

I cannot, of course, tell whether my supposition is correct. But what I assert, with the calmness of perfect certitude, is that the materialist has not taken the pains to analyse attentively what he calls the phenomenon of consciousness. Had he made this analysis and kept the elements in his mind, he would have seen that it is almost impossible to hook in any way a phenomenon of consciousness on to a material molecule.

In fact, also, to take this into account, we will not remain within the vagueness of the concept, but will take a particular example to argue upon, viz. that of an external perception. I open my window on a fine day, and I see before me a sunny plain, with, as far as the eye can reach, houses amongst the trees, and again more houses, the most distant of which are outlined against my far-off horizon. This is my mental phenomenon. And while I am at my window, my eyes fixed on the view, the anatomist declares that, starting from my retina, molecular vibrations travel along the optic nerve, cross each other at the chiasma, enter into the fascia, pass through the internal capsule and reach the hemispheres, or rather the occipital regions, of the brain, where, for the moment, we agree to localise the centre of projection of the visual sensations. This is my physical phenomenon. It now becomes the question of passing from this physical phenomena to the mental one. And here we are stopped by a really formidable difficulty.

My mental phenomenon is not entirely mental, as is usually supposed from the deceitful brevity of the phrase. It is in great part physical, for it can be decomposed into two elements, a consciousness and its object; and this object of the consciousness, this group of little houses I see in the plain, belongs to sensation—that is to say, to something physical—or, in other words, to matter.