The Mind and the Brain

This appears to me an insoluble question, and probably, even, a factitious one. The idea that an object can be modified in its nature or in its aspect comes to us through the perception of bodies. We see that, by attacking a metal with acids, this metal is modified, and that by heating a body its colour and form become changed; or that by electrifying a thread it acquires new properties; or that when we place glasses before our eyes we change the visible aspect of objects; or that, if we have inflammation of the eyelids, light is painful, and so on. All these familiar experiments represent to us the varied changes that a body perceived can undergo; but it must be carefully remarked that in cases of this kind the alteration in the body is produced by the action of a second body, that the effect is due to an intercourse between two objects. On the contrary, when we take the Kantian hypothesis, that the consciousness modifies that which it perceives, we are attributing to the consciousness an action which has been observed in the case of the objects, and are thus transporting into one domain that which belongs to a different one; and we are falling into the very common error which consists in losing sight of the proper nature of the consciousness and making out of it an object.

If we set aside this incorrect assimilation, there no longer remains any reason for refusing to admit that we perceive things as they are, and that the consciousness, by adding itself to objects, does not modify them.

Phenomena and appearances do not, then, strictly speaking, exist. Till proof to the contrary, we shall admit that everything we perceive is real, 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 its objects, let us see what concerns the perception, by the consciousness, of the relations existing between these objects themselves. The question is to ascertain whether the a priorists are right in admitting that the establishment of these relations is the work of the consciousness. The rôle of synthetic power that is thus attributed to consciousness is difficult to conceive unless we alter the definition of consciousness to fit the case. In accordance with the definition we have given and the idea we have of it, the consciousness makes us acquainted with what a thing is, but it adds nothing to it. It is not a power which begets objects, nor is it a power 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 and reveals the objects without creating them, we were, on the other hand, to admit that it makes up for this passivity by creating relations between objects. We dare not go so far as to say that this creation of relations is arbitrary and corresponds in no way to reality; or that, when we judge two neighbouring or similar objects, the relations of contiguity 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 some manner, attracted into the objects; it must be admitted that our intelligence does not apply its categories haphazard or from the caprice of the moment; and it must be admitted that it is led to apply them because it has perceived in the objects themselves a sign and a reason which are an invitation to this application, and its justification. On this hypothesis, therefore, contiguity and resemblance must exist in the things themselves, and must be perceived; for without this we should run the risk of finding similar that which is different, and contiguous that which has no relation of time or space. Whence it results, evidently, that our consciousness cannot create the connection completely, and then we are greatly tempted to conclude that it only possesses the faculty of perceiving it when it exists in the objects.27

According to this conception, the rôle of the consciousness in the perception of a connection is that of a witness, as in the perception of objects. The consciousness does not create, but it verifies. Resemblance is a physical property of objects, like colour; and contiguity is a physical property of objects, like form. The connections between the objects form part of the group object and not of the group consciousness, and they are just as independent of consciousness as are the objects themselves.

Against this conclusion we must anticipate several objections. One of them will probably consist in accentuating the difference existing between the object and the connection from the dynamical point of view. That the object may be passively contemplated by the consciousness can be understood, it will be said; but the relation is not only an object of perception—it is, further, a principle of action, a power of suggestion, and an agent of change.

It might, then, he supposed that the consciousness here finds a compensation for the rôle that has been withdrawn from it. If it is not the thing that creates the relation, it will be said, at least it is that which creates its efficacity of suggestion. Many psychologists have supposed that a relation has the power of evocation only when it has been perceived. The perception of resemblance precedes the action of resemblance. It is consequently the consciousness which assembles the ideas and gives them birth by perceiving their relations.

This error, for it is one, has long been wide-spread—indeed, it still persists.28 We have, however, no difficulty in understanding that the perception of a resemblance between two terms supposes them to be known; so long as only one of the terms is present to the consciousness, this perception does not exist; it cannot therefore possess the property of bringing to light the second term. Suggestion is therefore distinct from recognition; it is when suggestion has acted, when the resemblance in fact has brought the two terms together, that the consciousness, taking cognisance of the work accomplished, verifies the existence of a resemblance, and that this resemblance explains the suggestion.

Second objection: we are told that the relations between the objects—that is, the principal categories—must be of a mental nature, because they are a priori. That they are a priori means that they are at once anterior and superior to the experience. Let us see what this argument is worth.

It appears that it is somewhat misused. With regard to many of the categories, we are content to lay down the necessity of an abstract idea in order to explain the comprehension of a concrete one. It is said, for example: how can it be perceived that two sensations are successive, if we do not already possess the idea of time? The argument is not very convincing, because, for every kind of concrete perception it is possible to establish an abstract category.

It might be said of colour that it is impossible to perceive it unless it is known beforehand what colour is; and so on for a heap of other things. A more serious argument consists in saying that relations are a priori because they have a character of universality and of necessity which is not explained by experience, this last being always contingent and peculiar. But it is not necessary that a function should be mental for it to be a priori. The identification of the a priori with the mental is entirely gratuitous. We should here draw a distinction between the two senses of the a priori: anteriority and superiority.

A simple physical mechanism may be a priori, in the sense of anteriority. A house is a priori, in regard to the lodgers it receives; this book is a priori, in regard to its future readers. There is no difficulty in imagining the structure of our nervous system to be a priori, in regard to the excitements which are propagated in it. A nerve cell is formed, with its protoplasm, its nucleus and its nucleoli before being irritated; its properties precede its functions. If it be possible to admit that as a consequence of ancestral experiences the function has created the organ, the latter is now formed, and this it is which in its turn becomes anterior to the function. The notion of a priori has therefore nothing in it which is repugnant to physical nature.

Let us now take the a priori in the sense of superiority. Certain judgments of ours are, we are told, universal and necessary, and through this double character go beyond the evidence of experience. This is an exact fact which deserves to be explained, but it is not indispensable to explain it by allowing to the consciousness a source of special cognitions. The English school of philosophy have already attacked this problem in connection with the origin of axioms. The principle of their explanation lies in the virtue of what they have termed "inseparable association." They have supposed that when an association is often repeated it creates a habit of thought against which no further strife is possible. The mechanism of association itself should then add a special virtue to the contingency of facts. A hundred repetitions of related facts, for example, would give rise to so firm an association, that no further repetition would increase it.

I consider this explanation a very sound one in principle. It is right to put into association something more than into experience. I would only suggest a slight correction in detail. It is not the association forged by repetition which has this virtue of conveying the idea of necessity and universality, it is simply the uncontradicted association. It has been objected, in fact, and with reason, to the solution of Mill, that it insists on a long duration of experience, while axioms appear to be of an irresistible and universal truthfulness the moment they are conceived. And this is quite just. I should prefer to lay down as a law that every representation appears true, and that every link appears necessary and universal as soon as it is formed. This is its character from the first. It preserves it so long as no contradiction in fact, in reasoning, or in idea, comes to destroy it.29

What seems to stand out most clearly after all these explanations is the rôle which we ought to attribute to the consciousness. Two rival theories have been maintained: that of the mirror-consciousness and that of the focus-consciousness. It would seem—I merely say it would seem—that the first of these best harmonises with the preceding facts. For what seems most probable is, that the consciousness illuminates and reveals but does not act. The theory of the focus-consciousness adapts itself less to the mechanism of the association of ideas.

From this we come quite naturally to see in the intelligence only an inactive consciousness; at one moment it apprehends an object, and it is a perception or an idea; at another time it perceives a connection, and it is a judgment; at yet another, it perceives connections between connections, and it is an act of reason. But however subtle the object it contemplates may become, it does not depart from its contemplative attitude, and cognition is but a consciousness.

One step further, and we should get so far as to admit that the consciousness serves no purpose whatever, and that it is a useless luxury, since, if all efficacious virtue is to be found in the sensations and the ideas which we consider as material facts, the consciousness which reveals them adds nothing to, takes nothing from and modifies nothing in them; and everything would go on the same, nor would anything in this world be changed, if one day the light of consciousness were, by chance, to be put out. We might imagine a collection of automatons forming a human society as complicated as, and not different in appearance from, that of conscious beings; these automatons would make the same gestures, utter the same words as ourselves, would dispute, complain, cry, and make love like us; we might even imagine them capable, like us, of psychology. This is the thesis of the epiphenomenal consciousness which Huxley has boldly carried 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 that one can do nothing on this subject but form hypotheses.

CHAPTER VII

DEFINITION OF THE CONSCIOUSNESS—THE SEPARABILITY OF THE CONSCIOUSNESS FROM ITS OBJECT—DISCUSSION OF IDEALISM

One last question suggests itself with regard to the consciousness. In what measure is it separable from the object? Do the consciousness and its 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 same fact expressed in two different ways. All facts of our perception thus present themselves, and they are one. But our reason may outstrip our observation. We are able to make a distinction between the two elements being and being perceived. This is not an experimental but an ideological distinction, and an abstraction that language makes easy.

Can we go further, and suppose one of the parts thus analysed capable of existing without the other? Can sensation exist as physical expression, as an object; without being illuminated by the consciousness? Can the consciousness exist without having an object?

Let us first speak of the existence of the object when considered as separated from the consciousness. The problem is highly complicated.

It has sometimes been connected with the idealist thesis according to which the object of consciousness, being itself a modality of the consciousness, cannot exist apart from it—that is to say, outside the periods in which it is perceived. It would therefore result from this that this separation between existence and perception might be made, when it is admitted (contrary to the idealist hypothesis) that the object perceived is material and the consciousness which perceives it mental. In this case, it will be thought, there is no link of solidarity between the consciousness and its continuity. But I am not of that opinion. The union of the consciousness and its object is one of fact, which presents itself outside any hypothesis on the nature of the object. It is observation which demonstrates to us that we must perceive an object to be assured of its existence; the reason, moreover, confirms the necessity of this condition, which remains true whatever may be the "stuff" of the object.

Having stated this, the question is simply to know whether this observation of fact should be generalised or not. We may, it seems to me, decline to generalise it without falling into a contradiction in terms. It may be conceived that the objects which we are looking at continue to exist, without change, during the moments when we have lost sight of them. This seems reasonable enough, and is the opinion of "common" sense.30

The English philosophers, Bain and Mill, have combated this proposition with extraordinary ardour, like believers combating a heresy. But notwithstanding their attacks it remains intelligible, and the distinction between being and being perceived preserves its logical legitimacy. This may be represented, or may be thought; but can 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 world and the perception we have of it; its existence is one thing, and our perception of it is another. The existence of the world continues without interruption; our perception is continually interrupted by the most fortuitous causes, such as change of position, or even the blinking of the eyes; its existence is general, universal, independent of time and space; our perception is partial, particular, local, limited by the horizon of our senses, determined by the geographical position of our bodies, riddled by the distractions of our intelligence, deceived by the illusions of our minds, and above all diminished by the infirmity of our intelligence, which is able to comprehend so little of what it perceives. This is what we all admit in practice; the smallest of our acts implies the belief in something perceptible which is wider and more durable than our astonished perceptions. I could not write these lines unless I implicitly supposed that my inkstand, my paper, my pen, my room, and the surrounding world subsist when I do not see them. It is a postulate of practical life. It is also a postulate of science, which requires for its explanations of phenomena the supposition in them of an indwelling continuity. Natural science would become unintelligible if we were forced to suppose that with every eclipse of our perceptions material actions were suspended. There would be beginnings without sequences, and ends without beginnings.

Let us note also that acquired notions on the working of our nervous system allow us to give this postulate a most precise form: the external object is distinct from the nervous system and from the phenomena of perception which are produced when the nervous system is excited; it is therefore very easy to understand that this object continues to exist and to develop its properties, even when no brain vibrates in its neighbourhood.

Might we not, with the view of strengthening this conclusion as to the continuous existence of things, dispense with this postulate, which seems to have the character of a grace, of an alms granted to us? Might not this continuous existence of objects during the eclipses of our acts of consciousness, be demonstrated? It does not seem to me impossible. Let us suppose for a moment the correctness of the idealist thesis: all our legitimate knowledge of objects is contained within the narrow limits of actual sensation; then, we may ask, of what use is the reason? What is the use of the memory? These functions have precisely for their object the enlarging of the sphere of our sensations, which is limited in two principal ways, by time and by space. Thanks to the reason, we manage to see in some way that which our senses are unable to perceive, either because it is too distant from us, or because there are obstacles between us and the object, or because it is a past event or an event which has not yet taken place which is in question.

That the reason may be deceived is agreed. But will it be asserted that it is always deceived? Shall we go so far as to believe that this is an illegitimate mode of cognition? The idealist thesis, if consistent, cannot refuse to extend itself to this extreme conclusion; for a reasoned conclusion contains, when it has a meaning, a certain assertion on the order of nature, and this assertion is not a perception, since its precise object is to fill up the gaps in our perceptions. Not being a perception, it must be rejected, if one is an idealist.

The idealist will therefore keep strictly to the perception of the moment, and this is so small a thing when deprived of all the conjectures which enrich it, that the world, if reduced to this alone, would be but the skeleton of a world. There would then be no more science, no possibility of knowledge. But who could make up his mind thus to shut himself up in perception?

I suppose, indeed, that there will here be quibbling. This objection will be made: that in the hypothesis of a discontinuous existence of things, reason may continue to do its work, provided the intervention of a possible perception be supposed. Thus, I notice this morning, on going into my garden, that the pond which was dry yesterday is full of water. I conclude from this, "It has rained in the night." To be consistent with idealism, one must simply add: "If some one had been in the garden last night, he would have seen it rain." In this manner one must re-establish every time the rights of perception.

Be it so. But let us notice that this addition has no more importance than a prescribed formula in a notarial act; for instance, the presence of a second notary prescribed by the law, but always dispensed with in practice. This prescribed formula can always be imagined or even understood. We shall be in accord with idealism by the use of this easy little formula, "If some one had been there," or even by saying, "For a universal consciousness...." The difference of the realist and idealist theory becomes then purely verbal. This amounts to saying that it disappears. But there is always much verbalism in idealism.

One more objection: if this witness—the consciousness—suffices to give objects a continuity of existence, we may content ourselves with a less important witness. Why a man? The eyes of a mollusc would suffice, or those of infusoria, or even of a particle of protoplasm: living matter would become a condition of the existence of dead matter. This, we must acknowledge, is a singular condition, and this conclusion condemns the doctrine.

CHAPTER VIII

DEFINITION OF THE CONSCIOUSNESS—THE SEPARATION OF THE CONSCIOUSNESS FROM ITS OBJECT—THE UNCONSCIOUS

I ask myself whether it is possible, by going further along this road of the separation between the consciousness and its object, to admit that ideas may subsist during the periods when we are not conscious of them. It is the problem of unconsciousness that I am here stating.

One of the most simple processes of reasoning consists in treating ideas in the same manner as we have treated the external objects. We have admitted that the consciousness is a thing superadded to the external objects, like the light which lights up a landscape, but does not constitute it and may be extinguished without destroying it. We continue the same interpretation by saying that ideas prolong their existence while they are not being thought, in the same way and for the same motive that material bodies continue theirs while they are not being perceived. All that it seems permissible to say is that this conception 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 the consciousness, and have seen that we can still imagine the object continuing to exist. Is the converse possible? Let us suppose that the object is suppressed. Can the consciousness then continue to exist? On this last point it seems that doubt is not possible, and we must answer in the negative. A consciousness without an object, an empty consciousness, in consequence, cannot be conceived; it would be a zero—a pure nothingness; it could not manifest itself. We might admit, in strictness, that such a consciousness might exist virtually as a power which is not exercised, a reserve, a potentiality, or a possibility of being; but we cannot comprehend that this power can realise or actualize itself. There is therefore no actual consciousness without an object.

The problem we have just raised, that of the separability of the elements which compose an act of consciousness, is continued by another problem—that of unconsciousness. It is almost the same problem, for to ask one's self what becomes of a known thing when we separate from it the consciousness which at first accompanied it, is to ask one's self in what an unconscious phenomenon consists.

We have, till now, considered the two principal forms of unconsciousness—that in nature and that in thought. The first named unconsciousness does not generally bear that name, but is rather discussed under the name of idealism and realism. Whatever be their names, these two kinds of unconsciousness are conceivable, and the more so that they both belong to physical nature.

If we allow ourselves to be guided by the concept of separability, we shall now find that we have exhausted the whole series of possible problems, for we have examined all the possible separations between the consciousness and its objects; but if we use another concept, that of unconsciousness, we can go further and propound a new problem: can the consciousness become unconscious? But it is proper first to make a few distinctions. It is the rôle of metaphysics to make distinctions.31

Unconsciousness presupposes a death of the consciousness; but this death has its degrees, and before complete extinction we may conceive it to undergo many attenuations. There is, first, the diminution of consciousness.

Consciousness is a magnitude capable of increase and decrease, like sensation itself. According to the individual, consciousness may have a very large or a very small field, and may embrace at the same time a variable number of objects. I can pay attention to several things at the same time, but when I am tired it becomes more difficult to me. I lose in extension, or, as is still said, the field of consciousness is restricted. It may also lose not only in extent of surface, but in depth. We have all of us observed in our own selves moments of obscure consciousness when we understand dimly, and moments of luminous consciousness which carry one almost to the very bottom of things. It is difficult to consider those in the wrong who admit, with Leibnitz, the existence of small states of consciousness. The lessening of the consciousness is already our means of understanding the unconscious; unconsciousness is the limit of this reduction.32