The error proceeds from the use of concepts which cause the reality to

be lost sight of. The reality shows that every phenomenon of

consciousness consists in a mode of activity, an aggregate of

faculties which require an object to fasten on to and so realise

themselves, and that this object is furnished by matter. What we

always note in intuition is the union, the incarnation of

consciousness-matter. Our thoughts, our memories, our reasonings have

as object sensations, images--that is to say, things which, strictly

speaking, are as material as our own brains. It is therefore rather

childish to put all these workings of the spirit on another plane and

in another world than the workings of the brain since they are in

great part of the same nature as the last named and they contain so

many material elements. Now if we re-establish facts as they are, if

we admit a parallelism between physical phenomena, on the one hand,

and phenomena at once physical and psychical, on the other, the

parallelist hypothesis loses every sort of meaning. It ceases to

present to us the image of two phenomena of an absolutely different

order, 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. If

there is anything material in the psychical part, the opposition of

nature no longer exists between the two terms; they become identical.

Very often, certain parallelists, after thinking they have discovered

the duality of nature, endeavour to bring it back to unity by

supposing that the two faces of the reality are as two effects of one

unique reality, inaccessible to our senses and underlying appearances.

Why go so far afield to seek unity? It is trouble in vain: for it is

to 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 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_."]

CHAPTER IV

MODERN THEORIES

It may be thought that the objection taken above to parallelism and

materialism is personal to myself, because I have put it forward as

the consequence of my analysis of the respective shares of thought and

matter in every act of cognition. This is not so. I am here in harmony

with other philosophers who arrived at the same conclusions long

before me, and it may be useful to quote them.

We will begin with the prince of idealists, Berkeley. "'Everything you

know or conceive other than spirits,' says Philonous to Hylas, 'is but

your ideas; so then when you say that all ideas are occasioned by

impressions made in the brain, either you conceive this brain or you

do not. If you conceive it, you are in that case talking of ideas

imprinted in an idea which is the cause of this very idea, which is

absurd. If you do not conceive it, you are talking unintelligibly, you

are not forming a reasonable hypothesis.' 'How can it be reasonable,'

he goes on to say, 'to think that the brain, which is a sensible

thing, _i.e._ which can be apprehended by the senses--an idea

consequently which only exists in the mind--is the cause of our other

ideas?'"[47]

Thus, in the reasoning of Berkeley, the function of the brain cannot

explain 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 very

different standpoint from that of idealism. He takes the word image in

the vaguest conceivable sense. To explain the meaning of this word he

simply says: "images which are perceived when I open my senses, and

unperceived when I close them." He also remarks that the external

objects are images, and that the brain and its molecular disturbances

are likewise images. And he adds, "For this image which I call

cerebral disturbance to generate the external images, it would have to

contain them in one way or another, and the representation of the

whole material universe would have to be implicated in that of this

molecular movement. Now, it is enough to enunciate such a proposition

to reveal its absurdity."[48]

It will be seen that this reasoning is the same as Berkeley's, though

the two authors are reasoning on objects that are different; according

to Berkeley, the brain and the states of conscience are psychical

states; according to Bergson, the definition of the nature of these

two objects designated by the term image is more comprehensive, but

the essential of his argument is independent of this definition. It is

enough that the two terms should be of similar nature for one to be

unable to generate the other.

My own argument in its turn comes rather near the preceding ones. For

the idea of Berkeley, and the image of Bergson, I substitute the term

matter. I say that the brain is matter, and that the perception of any

object is perception of matter, and I think it is not easy to explain

how from this brain can issue this perception, since that would be to

admit that from one matter may come forth another matter. There is

certainly here a great difficulty.

M. Bergson has thought to overcome it by attacking it in the following

way. He has the very ingenious idea of changing the position of the

representation in relation to the cerebral movement. The materialist

places the representation after this movement and derives it from the

movement; the parallelist places it by the side of the movement and in

equivalence to it. M. Bergson places it before the movement, and

supposes it to play with regard to it the part of exciting cause, or

simply that of initiator. This cerebral movement becomes an effect of

the representation and a motor effect. Consequently the nervous system

passes into the state of motor organ: the sensory nerves are not, as

supposed, true sensory nerves, but they are the commencements of motor

nerves, the aim of which is to lead the motor excitements to the

centres which play the part of commutators and direct the current,

sometimes by one set of nerves, sometimes by others. The nervous

system is like a tool held in the hand: it is a vehicle for action, we

are told, and not a substratum for cognition. I cannot here say with

what ingenuity, with what powerful logic, and with what close

continuity of ideas M. Bergson develops his system, nor with what

address he braves its difficulties.

His mind is remarkable alike for its power of systematisation and its

suppleness of adaptation. Before commencing to criticise him, I am

anxious to say how much I admire him, how much I agree with him

throughout the critical part of his work, and how much I owe to the

perusal of his book, _Matière et Mémoire_. Though I was led into

metaphysics by private needs, though some of the ideas I have set

forth above were conceptions of my own (for example, the criticism of

the mechanical theory of matter, and the definition of sensation),

before I had read M. Bergson's book, it cannot be denied that its

perusal has so strongly modified my ideas that a great part of these

are due to him without my feeling capable of exactly discerning which;

for ideas have a much more impersonal character than observations and

experiments. It would therefore have been ungrateful to criticise him

before having rendered him this tribute.

There are, in M. Bergson's theory, a few assertions which surprise us

a little, like everything which runs counter to old habits. It has

always been supposed that our body is the receptacle of our

psychological phenomena. We store our reminiscences in our nerve

centres; we put the state of our emotions in the perturbations of

certain apparatus; we find the physical basis of our efforts of will

and of attention in the sensations of muscular tension born in our

limbs or trunk. Directly we believe that the nervous system is no

longer the depository of these states, we must change their domicile;

and where are they to be placed? Here the theory becomes obscure and

vague, and custom renders it difficult to understand the situation of

the mind outside the body. M. Bergson places memory in planes of

consciousness far removed from action, and perception he places in the

very object we perceive.

If I look at my bookcase, my thought is in my books; if I look at the

sky, my thought is in a star.[49] It is very difficult to criticise

ideas such as these, because one is never certain that one understands

them. I will therefore not linger over them, notwithstanding the

mistrust which they inspire in me.

But what seems to me to require proof is the function M. Bergson is

led to attribute to the sensory nerves. To his mind, it is not exact

to say that the excitement of a sensory nerve excites sensation. This

would be a wrong description, for, according to him, every nerve, even

a sensory one, serves as a motor; it conducts the disturbance which,

passing through the central commutator, flows finally into the

muscles. But then, whence comes it that I think I feel a sensation

when my sensory nerve is touched? Whence comes it that a pressure on

the epitrochlear nerve gives me a tingling in the hand? Whence comes

it that a blow on the eyeball gives me a fleeting impression of light?

One must read the page where M. Bergson struggles against what seems

to me the evidence of the facts. "If, for one reason or another," he

says, "the excitement no longer passes, it would be strange if the

corresponding perception took place, since this perception would then

put our body in relation with points of space which would no longer

invite it to make a choice. Divide the optic nerve of any animal; the

disturbance starting from the luminous point is no longer transmitted

to the brain, and thence to the motor nerves. The thread which

connected the external object to the motor mechanism of the animal by

enveloping the optic nerve, is severed; the visual perception has

therefore become powerless, and in this powerlessness consists

unconsciousness." This argument is more clever than convincing. It is

not convincing, because it consists in exaggerating beyond all reason

a very real fact, that of the relation which can be discovered between

our sensations and our movements. We believe, with M. Bergson, that it

is absolutely correct to see in action the end and the _raison d'être_

of our intelligence and our sensibility. But does it follow that every

degree, every shade, every detail of sensation, even the most

insignificant, has any importance for the action? The variations of

sensibility are much more numerous than those of movements and of

adaptation; very probably, as is seen in an attentive study of

infancy, sensibility precedes the power of motion in its

differentiations. A child shows an extraordinary acuteness of

perception at an age when its hand is still very clumsy. The

correlation, then, is not absolute. And then even if it were so, it

would not follow that the suppression of any movement would produce by

rebound the suppression of the sensation to which this movement

habitually corresponds. On this hypothesis, a sensation which loses

its motor effect becomes useless. Be it so; but this does not prove

that the uselessness of a sensation is synonymous with insensibility.

I can very well imagine the movement being suppressed and the useless

sensation continuing to evoke images and to be perceived. Does not

this occur daily? There are patients who, after an attack of paralysis

remain paralysed in one limb, which loses the voluntary movement, but

does not necessarily lose its sensibility. Many clear cases are

observed in which this dissociation takes place.

I therefore own that I cannot follow M. Bergson in his deduction. As a

physiologist, I am obliged to believe firmly in the existence of the

sensory nerves, and therefore I continue to suppose that our conscious

sensations are consequent to the excitement of these nerves and

subordinate to their integrity. Now, as therein lies, unless I

mistake, the essential postulate, the heart of M. Bergson's theory, by

not admitting it I must regretfully reject the whole.

FOOTNOTES:

[Footnote 47: I borrow this quotation from RENOUVIER, _Le

Personnellisme_, p. 263.]

[Footnote 48: _Matière et Mémoire_, p. 3. The author has returned to

this point more at length in a communication to the Congrès de

Philosophie de Génève, in 1904. See _Revue de Métaphysique et de

Morale_, Nov. 1904, communication from H. BERGSON entitled "Le

Paralogisme psycho-physiologique." Here is a passage from this article

which expresses the same idea: "To say that the image of the

surrounding world issues from this image (from the cerebral movement),

or that it expresses itself by this image, or that it arises as soon

as this image is suggested, or that one gives it to one's self by

giving one's self this image, would be to contradict one's self; since

these 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 of

representation, 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 the

above criticisms on their systems, have found no answer to them; my

criticisms have appeared to them just, but nevertheless they have

continued to abide by their own systems, probably because they were

bound to have one. We do not destroy an erroneous idea when we do not

replace it by another.

This has decided me to set forth some personal views which,

provisionally, and for want of better, might be substituted for the

old 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. They

present their systems as a well-connected whole, and they set forth

its different parts, even the boldest of them, in the same dogmatic

tone, and without warning that we ought to attach very unequal degrees

of confidence to these various parts. This is a deplorable method, and

to it is perhaps due the kind of disdain that observers and

experimentalists feel for metaphysics--a disdain often without

justification, for all is not false, and everything is not

hypothetical, in metaphysics. There are in it demonstrations,

analyses, and criticisms, especially the last, which appear to me as

exact and as certain as an observation or experiment. The mistake lies

in mixing up together in a statement, without distinction, the certain

with 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 of

the abuse of speculation. It is especially by the cultivation of the

sciences of observation that we foster in ourselves the precious sense

of proof, because we can check it any minute by experimental

verification. When we are working at a distance from the facts, this

sense of proof gets thinner, and there is lost that feeling of

responsibility and fear of seeing one's assertions contradicted by a

decisive countervailing observation, which is felt by every observer.

One acquires the unbearable pride which I note in Kant, and one

abandons one's self to the spirit of construction. I am speaking from

personal experience. I have several times detected within me this bad

spirit of construction, I have been seeking to group several facts of

observation under the same idea, and then I have discovered that I was

belittling and depreciating those facts which did not fit in with the

idea.

The hypothesis I now present on the relations of the mind and the

brain has, for me, the advantage of bringing to light the precise

conditions which a solution of this great problem must satisfy for

this solution to be worthy of discussion.

These conditions are very numerous. I shall not indicate them all

successively; but here are two which are particularly important.

1. The manifestations of the consciousness are conditioned by the

brain. Let us suspend, by any means, the activity of the encephalic

mass, by arresting the circulation of the blood for example, and the

psychic function is at once inhibited. Compress the carotid, and you

obtain the clouding-over of the intellect. Or, instead of a total

abolition, you can have one in detail; sever a sensory nerve with the

bistoury, and all the sensations which that nerve transmits to the

brain are suppressed. Consciousness appears only when the molecular

disturbance reaches the nerve centres; everything takes place in the

same way as if this disturbance released the consciousness.

Consciousness also accompanies or follows certain material states of

the nerve centres, such as the waves which traverse the sensory

nerves, which exercise reflex action in the cells, and which propagate

themselves in the motor nerves. It is to the production, the

distribution, and the integrity of this nervous influx that the

consciousness is closely linked. It there finds one of the conditions

of its apparition.

2. On the other hand, the consciousness remains in complete ignorance

of these intra-cerebral phenomena. It does not perceive the nerve-wave

which sets it in motion, it knows nothing of its peculiarities, of its

trajectory, or the length of its course. In this sense it may be said

that it is in no degree an anatomist; it has no idea of all the

peculiarities of the nerve-wave which form part of its cerebral

history from the moment when these peculiarities are out of relation

with the properties of external objects.

One sometimes wonders that our consciousness is not aware that the

objects we perceive with our two eyes correspond to a double

undulation, namely, that of the right and that of the left, and that

the image is reversed on the retina, so that it is the rods of the

right which are impressed by objects on our left, and the rods of the

upper part by objects below our eyes. These are, it has been very

justly said, factitious problems, imaginary difficulties which do not

exist. There is no need to explain, for instance, direct vision by a

reversed image, because our consciousness is not aware that the image

on the retina is reversed. In order to take account of this, we should

require another eye to see this image. This answer appears

particularly to the point. It will be found that it is absolutely

correct if we reflect that this case of the unfelt inversion of the

image on the retina is but one example of the anatomical ignorance of

the consciousness.

It might also be declared, in the same order of ideas, that our

consciousness is ignorant, that excitements of the eye cross each

other at the level of the chiasma, and pass through the internal

capsule, and that the majority of the visual excitements of an eye are

received by the opposite hemisphere.

A rather confused notion of these facts has formed itself in the minds

of several critics, and I can discern the proof of this in the

language they use. It will be said, for example, that the idea exists

in the consciousness or in the mind, and phrases like the following

will be avoided: "I think with my brain"--the suggestion consists in

introducing an idea in the brain--"The nerve cell perceives and

reasons, &c." Ordinarily these forms of speech are criticised because

they appear to have the defect of establishing a confusion between two

irreducible elements, the physical and the mental. I think the error

of language proceeds from another cause, since I do not admit this

distinction between the physical and the mental. I think that the

error consists in supposing vaguely that the consciousness

comprehends intra-cerebral phenomena, whereas it ignores them.

Let me repeat that there is no such thing as intra-cerebral

sensibility. The consciousness is absolutely insensitive with regard

to the dispositions of the cerebral substance and its mode of work. It

is not the nervous undulation which our consciousness perceives, but

the exciting cause of this wave--that is, the external object. The

consciousness does not feel that which is quite close to it, but is

informed of that which passes much further off. Nothing that is

produced inside the cranium interests it; it is solely occupied with

objects of which the situation is extra-cranial. It does not penetrate

into the brain, we might say, but spreads itself like a sheet over the

periphery of the body, and thence springs into the midst of the

external objects.

There is, therefore, I do not say a contradiction, but a very striking

contrast between these two facts. The consciousness is conditioned,

kept up, and nourished by the working of the cerebral substance, but

knows nothing of what passes in the interior of that substance. This

consciousness might itself be compared to a parasitical organism which

plunges its tap roots into the nerve centres, and of which the organs

of perception, borne on long stalks, emerge from the cranium and

perceive everything outside that cranium. But this is, of course,

only a rough image.

Strictly, it is possible to explain this distribution of the

conscience, singular as it is at first sight, by those reasons of

practical utility which are so powerful in the history of evolution.

A living being has to know the world external to himself in order to

adapt and preadapt himself to it, for it is in this outer world that

he finds food, shelter, beings of his own species, and the means of

work, and it is on this world of objects that he acts in every

possible way by the contractions of his muscles. But with regard to

intracephalic actions, they are outside the ordinary sphere of our

actions. There is no daily need to know them, and we can understand

that the consciousness has not found very pressing utilitarian motives

for development in that direction. One must be an histologist or a

surgeon to find an appreciable interest in studying the structure of

the nerve cell or the topography of the cerebral centres.

We can therefore explain well enough, by the general laws of

adaptation, 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 the

consciousness, directly aroused by a nerve-wave, does not perceive

this undulation, but in its stead the external object. Let us first

note that between the external object and the nervous influx there is

the relation of cause to effect. It is only the effect which reaches

us, our nerve cells, and our consciousness. What must be explained is

how a cognition (if such a word may be employed here) of the effect

can excite the consciousness of the cause. It is clear that the effect

does not resemble the cause, as quality: the orange I am looking at

has no resemblance with the brain wave which at this moment is

traversing my optic nerve; but this effect contains everything which

was in the cause, or, more exactly, all that part of the cause of

which we have perception. Since it is only by the intermediary of our

nervous system that we perceive the object, all the properties capable

of being perceived are communicated to our nervous system and

inscribed in the nerve wave. The effect produced therefore is the

measure of our perception of the cause. This is absolutely certain.

All bodies possess an infinity of properties which escape our

cognitions; because, as excitants of our organism, these properties

are wanting in the intensity or the quality necessary to make it

vibrate; they have not been tuned in unison with our nervous chords.

And, inversely, all we perceive of the mechanical, physical, and

chemical properties of a body is contained in the vibration this body

succeeds in propagating through our cerebral atmosphere. There is in

this a phenomenon of transmission analogous to that which is produced

when an air of music is sent along a wire; the whole concert heard at

the other extremity of the wire has travelled in the form of delicate

vibrations.

There must therefore exist, though unperceived by our senses, a sort

of kinship between the qualities of the external objects and the

vibrations of our nerves. This is sometimes forgotten. The theory of

the specific energy of the nerves causes it to be overlooked. As we

see that the quality of the sensation depends on the nerve that is

excited, one is inclined to minimise the importance of the excitant.

It is relegated to the position of a proximate cause with regard to

the vibration of the nerve, as the striking of a key on the piano is

the proximate cause of the vibration of a string, which always gives

the same degree of sound whether struck by the forefinger or third

finger, or by a pencil or any other body. It will be seen at once that

this comparison is inexact. The specific property of our nerves does

not prevent our knowing the form of the excitant, and our nerves are

only comparable to piano strings if we grant to these the property of

vibrating differently according to the nature of the bodies which

strike them.

How is it that the nerve wave, if it be the depository of the whole of

the physical properties perceived in the object, resembles it so

little? It is because--this is my hypothesis--these properties, if

they are in the undulation, are not there alone. The undulation is the

work of two collaborators: it expresses both the nature of the object

which provokes it and that of the nervous apparatus which is its

vehicle. It is like the furrow traced in the wax of the phonograph

which expresses the collaboration of an aërial vibration with a

stylus, a cylinder, and a clock-work movement. This engraved line

resembles, in short, neither the phonographic apparatus nor the aërial

vibration, although it results from the combination of the two.

Similarly, I suppose that if the nervous vibration resembles so little

the excitant which gives it birth, it is because the factor nervous

system adds its effect to the factor external object. Each of these

factors represents a different property: the external object

represents a cognition and the nervous system an excitement.

Let us imagine that we succeed in separating these two effects. It

will be conceived, theoretically, that a separation of this kind will

lay bare the hidden resemblances, giving to each collaborator the

part which belongs to it. The excitement, for instance, will be

suppressed, and the cognition will be retained. Is it possible to

make, or at least to imagine, such an analysis? Perhaps: for, of these

two competing activities, one is variable, since it depends on the

constantly changing nature of the objects which come into relation

with us; the other, on the contrary, is a constant, since it expresses

the contribution of our nerve substance, and, though this last is of

very unstable composition, it necessarily varies much less than the

series of excitants. We consequently see faintly that these two

elements differ sufficiently in character for us to be able to suppose

that they are separable by analysis.

But how could this analysis be made? Evidently not by chemical or

physical means: we have no need here of reagents, prisms, centrifugal

apparatus, permeable membranes, or anything of that kind. It will

suffice to suppose that it is the consciousness itself that is the

dialyser. It acts by virtue of its own laws--that is to say, by

changes in intensity. Supposing that sensibility increases for the

variable elements of the undulation, and becomes insensible for the

constant elements. The effect will be the same as a material

dissociation by chemical analysis: there will be an elimination of

certain elements and the retention of others.

Now, all we know of the consciousness authorises us to entrust this

rôle to it, for it is within the range of its habits. We know that

change is the law of consciousness, that it is effaced when the

excitements are uniform, and is renewed by their differences or their

novelty. A continued or too often repeated excitement ceases in time

to be perceived. It is to condense these facts into a formula that

Bain speaks of the law of relativity of cognition, and, in spite of a

few ambiguities on the part of Spencer and of Bain himself in the

definition of this law,[50] the formula with the sense I have just

indicated is worth preserving.

Let us see what becomes of it, when my hypothesis is adopted. It

explains how certain excitements proceeding from the objects--that is

to say, forming part of the variable element--cease to be perceived

when they are repeated and tend to become constant. _A fortiori_, it

seems to me, should the same law explain how the constant element _par

excellence_, the one which never varies from the first hour, is never

perceived. There is, in the concert of the sounds of nature, an

accompaniment so monotonous that it is no longer perceived; and the

melody alone continues to be heard.

It is in this precisely that my hypothesis consists. We will suppose a

nerve current starting from one of the organs of the senses, when it

is excited by some object or other, and arriving at the centre of the

brain. This current contains all the properties of the object, its

colour, its form, its size, its thousand details of structure, its

weight, its sonorous qualities, &c., &c., properties combined with and

connected by the properties of the nerve-organ in which the current is

propagated. The consciousness remains insensible to those nervous

properties of the current which are so often repeated that they are

annulled; it perceives, on the contrary, its variable and accidental

properties which express the nature of the excitant. By this partial

sensibility, the consciousness lays bare that which, in the nerve

current, represents the object--that is to say, a cognition; and this

operation is equivalent to a transformation of the current into a

perception, image, or idea. There is not, strictly speaking, a

transformation, but an analysis; only, the practical result is the

same as that of a transformation, and is obtained without its being

necessary to suppose the transmutation of a physical into a mental

phenomenon.

Let us place ourselves now at the moment when the analysis I am

supposing to be possible has just been effected. Our consciousness

then assists at the unrolling of representations which correspond to

the outer world. These representations are not, or do not appear to

be, lodged in the brain; and it is not necessary to suppose a special

operation which, taking them in the brain, should project them to the

periphery of our nerves. This transport would be useless, since for

the consciousness the brain does not exist: the brain, with its fibres

and cells, is not felt; it therefore supplies no _datum_ to enable us

to judge whether the representation is external or internal with

regard to it. In other words, the representation is only localised in

relation to itself; there is no determinate position other than that

of one representation in relation to another. We may therefore reject

as inexact the pretended law of eccentricity of the physiologists, who

suppose that sensation is first perceived as it were centrally, and

then, by an added act, is localised at the peripheric extremity of the

nerve. This argument would only be correct if we admitted that the

brain is perceived by the consciousness of the brain. I have already

said that the consciousness is not an anatomist, and that therefore

this problem does not present itself.

Such as it is, this hypothesis appears to me to present the advantage

of explaining the reason why our consciousness coincides, in certain

circumstances, with the actions of the brain, and, in others, does not

come near them. In other words, it contains an explanation of the

unconscious. I can show this by quoting certain exact facts, of which

the explanation has been hitherto thought to present difficulties, but

which become very easy to understand on the present hypothesis. The

first of these facts relates to the psychology of the motor current.

This current has been a great feature in the studies which have been

made on the feeling of effort and on the physical basis of the will.

The motor current is that which, starting from the cerebral cells of

the motor region, travels by way of the fibres of the pyramidal tract

into the muscles of the body; and it is centrifugal in direction.

Researches have been made as to whether we are or may be conscious of

this current; or rather, the question has been put in somewhat

different terms. It has been asked whether a psychological state can

be the counterpart of this motor current,--if, for example, the

feeling of mental effort produced in us at the moment of executing a

difficult act or of taking a grave resolution, might not have this

motor current for a basis.

The opinion which has prevailed is in the negative. We have

recognised--a good deal on the faith of experiment, and a little also

for theoretical reasons--that no sensation is awakened by the

centrifugal current. As to the sensation of effort, it has been agreed

to place it elsewhere. We put it among the centripetal sensations

which, are produced as the movement outlines itself, and which proceed

from the contracted muscles, the stretched ligaments, and the

frictional movements of the articulations. Effort would therefore form

part of all the psychical phenomenology, which is the duplicate of

those sensory currents which are centripetal in direction.

In the long run, I can see no sort of theoretical reason for

subordinating the consciousness to the direction of the nerve current,

and for supposing that the consciousness is aroused when this current

is centripetal, and that it cannot follow the centrifugal current. But

this point matters little. My hypothesis would fairly well explain why

the motor current remains unconscious; it explains the affair by

taking into consideration the nature of this current and not its

direction. This current is a motor one because it is born in the

central cells, because it is a discharge from these cells, and is of

entirely nervous origin. Since it does not correspond with the

perception of an object--the ever varying object--it is always the

same 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 flow

without consciousness.

This same kind of hypothesis supplies us with the reasons why a given

sensory current may be, according to circumstances, either conscious

or unconscious. The consciousness resulting from the analysis of the

molecular wave is, as it were, a supplementary work which may be

subsequently added to the realised wave. The propagation of the wave

is the essential fact--there is always time to become conscious of it

afterwards. It is thus that we happen, in moments of abstraction, to

remain insensible to certain even very powerful excitements. Our

nervous system registers them, nevertheless, and we can find them

again, later on, within the memory. This is the effect of a belated

analysis.

The converse phenomenon occurs much more frequently. We remark many

actions and perceptions which occur the first time with consciousness,

emotion, and effort. Then, when they are repeated, as coordination

becomes stronger and easier, the reflex consciousness of the operation

becomes feebler. This is the law of habit, which slowly carries us

towards automatism. These observations have even been extended, and

the endeavour made to apply them to the explanation of the origin of

reflex actions and of instincts which have all started with

consciousness. This is a rather bold attempt, for it meets with many

serious difficulties in execution; but the idea seems fairly correct,

and is acceptable if we may limit it. It is certain that the

consciousness accompanies the effort towards the untried, and perishes

as soon as it is realised. Whence comes this singular dilemma

propounded to it by nature: to create something new or perish? It

really seems that my hypothesis explains this. Every new act is

produced by nerve currents, which contain many of those variable

elements which the consciousness perceives; but, in proportion as the

action of the brain repeats itself and becomes more precise and more

exact, this variable element becomes attenuated, falls to its lowest

pitch, and may even disappear in the fixation of habit and instinct.

My hypothesis much resembles the system of parallelism. It perfects

it, as it seems to me, as much as the latter has perfected

materialism. We indeed admit a kind of parallelism between the

consciousness and the object of cognition; but these two series are

not independent, not simply placed in juxtaposition as is possible in

ordinary parallelism; they are united and fused together so as to

complete each other. This new theory appears to me to represent a

better form of the series of attempts which have been inspired by the

common necessity of making the phenomena of consciousness accord with

the determinism of physical facts.

I hold fast to this physical determinism, and accept a strictly

mechanical conception of the functions of the nervous system. In my

idea, the currents which pass through the cerebral mass follow each

other without interruption, from the sensorial periphery to the motor

periphery; it is they, and they alone, which excite the movements of

the body by acting on the muscles. Parallelism recognises all these

things, and I do likewise.

Let us now see the advantages of this new system. First, it contains

no paralogism, no logical or psychological error, since it does not

advance the supposition that the mental differs by its nature from the

physical phenomenon. We have discussed above the consequences of this

error, They are here avoided. In the second place, it is explanatory,

at least in a certain measure, since the formula we employ allows us

to understand, better than by the principle of a simple juxtaposition,

why certain nerve currents flow in the light of consciousness, while

others are plunged into the darkness of unconsciousness. This law of

consciousness, which Bain called the law of relativity, becomes, when

embodied with my theory of the relations of the physical to the moral,

an explanation of the distribution of consciousness through the

actions of the brain.

I ask myself whether the explanation I have devised ought to be

literally preserved. Perhaps not. I have endeavoured less to present a

ready-made solution than to indicate the direction in which we ought

to look for one. The law of consciousness which I have used to explain

the transformation of a nerve current into perception and images is

only an empirical law produced by the generalisation of particular

observations. Until now there has been, so far as I know, no attempt

to ascertain whether this law of consciousness, notwithstanding the

general nature which some authors incline to ascribe to it, might not

explain itself by some more general facts, and might not fit, as a

particular case, into a more comprehensive frame. To be brief, this is

very possible. I have not troubled myself about it, and I have made a

transcendental use of this empirical law; for I have impliedly

supposed it to be a first principle, capable of accounting for the

development of the consciousness, but itself incapable of explanation.

If other observers discover that that which to me has appeared

inexplicable, may be explained by quite peculiar causes, it is clear

that my theory must be abandoned or modified. New theories must then

be sought for, which will probably consist in recognising different

properties in the consciousness. A little thought will discover

several, I have no doubt. By way of suggestion, I will indicate one

of these hypothetical possibilities: "The consciousness has the

faculty of reading in the effect that which existed in the cause." It

is not rash to believe that by working out this idea, a certain

solution would be discovered. Moreover, the essential is, I repeat,

less to find a solution than to take account of the point which

requires one; and metaphysics seem to me especially useful when it

shows us where the gap in our knowledge exists and what are the

conditions required to fill this gap.

Above all, I adhere to this idea, which has been one of the guiding

forces of this book: there exists at the bottom of all the phenomena

of the intelligence, a duality. To form a true phenomenon, there must

be at once a consciousness and an object. According to passing

tendencies, either of temperament or of fashion, preponderance has

been given sometimes to one of the terms of this couple, sometimes to

the other. The idealist declares: "Thought creates the world." The

materialist answers: "The matter of the brain creates thought."

Between these two extreme opinions, the one as unjustifiable as the

other in the excesses they commit, we take up an intermediate

position. Looking at the balance, we see no argument capable of being

placed in the scale of the consciousness which may not be neutralised

by an argument placed in the scale of the object; and if we had to

give our final verdict we should say: "The consciousness and matter

have equal rights," thus leaving to every one the power to place, in

this conception of an equality of rights, the hopes of survival of

which his heart has need.

FOOTNOTES:

[Footnote 50: The _équivoque_ perpetrated by BAIN and SPENCER consists

in supposing that the consciousness bears solely on differences. This

is going too far. I confine myself to admitting that, if sensation is

not changed from time to time, the consciousness becomes weaker and

disappears.]

CHAPTER VI

RECAPITULATION

I ask permission to reproduce here a communication made by me in

December 1904 to the Société Française de Philosophie. I there set

forth briefly the ideas which I have just developed in this book. This

succinct _exposé_ may be useful as a recapitulation of the argument.

_Description of Matter._--The physicists who are seeking for a

conception of the Inmost structure of matter in order to explain the

very numerous phenomena they perceive, fancy they can connect them

with other phenomena, less numerous, but of the same order. They thus

consider matter in itself.

We psychologists add to matter something more, viz. the observer. We

consider matter and define it by its relations to our modes of

knowledge--that is to say, by bearing in mind that it is conditioned

by our external perception. These are two different points of view.

In developing our own standpoint, we note that of the outer world we

are acquainted with nothing but our sensations: if we propound this

limit, it is because many observations and experiments show that,

between the external object and ourselves, there is but one

intermediary, the nervous system, and that we only perceive the

modifications 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 not

necessarily similar to the objects which excite them; for the quality

of each sensation depends on what is called the specific energy of the

nerve excited. Thus, whether the optic nerve be appealed to by a ray

of light, an electric current, or a mechanical shock, it always gives

the same answer, and this answer is the sensation of light.

It follows that our nervous system itself is only known to us as

regards its structure by the intermediary of sensations, and we are

not otherwise more informed upon its nature than upon that of any

other object whatever.

In the second place, a much more serious consequence is that all our

sensations being equally false, so far as they are copies of the

excitants which provoke them, one has no right to use any of these

sensations to represent to ourselves the inmost structure of matter.

The theories to which many physicists still cling, which consist in

explaining all the modalities of matter by different combinations of

movement, start from false premises. Their error consists in

explaining the whole body of our sensations by certain particular

sensations of the eye, of the touch, and of the muscular sense, in

which analysis discovers the elements and the source of the

representation of motion. Now these particular sensations have no more

objective 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 is

sought to penetrate the inmost nature, one of them is as radically

false as the other.

It is true that a certain number of persons will think to escape from

our conclusion, because they do not accept our starting point. There

exist, in fact, several systems which propound that the outer world is

known to us directly without the intermediary of a _tertium quid_,

that is, of sensation. In the first place, the spiritists are

convinced that disembodied souls can remain spectators of terrestrial

life, and, consequently, can perceive it without the interposition of

organs. On the other hand, some German authors have recently

maintained, by rather curious reasoning, that the specific energy of

our nervous system does not transform the excitants, and that our

sensations 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 by

direct comprehension we have cognisance of the objects without mystery

and as they are. Let this be admitted. It will change nothing in our

conclusions, and for the following reasons.

We have said that no kind of our sensations--neither the visual, the

tactile, nor the muscular--permits us to represent to ourselves the

inmost structure of matter, because all sensations, without exception,

are false, as copies of material objects. We are now assured that we

are 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 the

same thing as if all are false. If all are true, it is impossible to

make any choice among them, to retain only the sensations of sight and

touch, and to use them in the construction of a mechanical theory, to

the exclusion of the others. For it is impossible for us to explain

some by the others. If all are equally true, they all have the same

right to represent the structure of matter, and, as they are

irreconcilable, no theory can be formed from their synthesis.

Let us, consequently, conclude this: whatever hypothesis may be built

up on the relations possibly existing between matter and our

sensations, we are forbidden to make a theory of matter in the terms

of our sensations.

That is what I think of matter, understood as the inmost structure of

bodies--of unknowable and metaphysical matter. I shall not speak of it

again; and henceforth when I use the word matter, it will be in quite

a different acceptation--it will be empirical and physical matter,

such as it appears to us in our sensations. It must therefore be

understood that from this moment we change our ground. We leave the

world of _noumena_ and enter that of phenomena.

_Definition of Mind._--Generally, to define the mind, we oppose the

concept of mind to the concept of matter, with the result that we get

extremely vague images in our thoughts. It is preferable to replace

the concepts by facts, and to proceed to an inventory of all mental

phenomena.

Now, in the course of this inventory, we perceive that we have

continually to do with two orders of elements, which are united in

reality, but which our thought may consider as isolated. One of these

elements is represented by those states which we designate by the name

of sensations, images, emotions, &c.; the other element is the

consciousness of these sensations, the cognition of these images, the

fact of experiencing these emotions. It is, in other words, a special

activity of which these states are the object and, as it were, the

point of application--an activity which consists in perceiving,

judging, comparing, understanding, and willing. To make our inventory

orderly, let us deal with these two elements separately and begin with

the first.

We will first examine sensation: let us put aside that which is the

fact of feeling, and retain that which is felt. Thus defined and

slightly condensed, what is sensation? Until now we have employed the

word in the very vague sense of a _tertium quid_ interposed between

the object and ourselves. Now we have to be more precise, and to

inquire whether sensation is a physical or a mental thing. I need not

tell you that on this point every possible opinion has been held. My

own opinion is that sensation should be considered as a physical

phenomenon; sensation, be it understood, in the sense of impression

felt, and not in that of capacity to feel.

Here are the arguments I invoke for the support of my thesis: in the

first place, popular opinion, which identifies matter with what we

see, and with what we touch--that is to say, with sensation. This

popular opinion represents a primitive attitude, a family possession

which we have the right to retain, so long as it is not proved to us

to be false: next, this remark, that by its mode of apparition at once

unexpected, the revealer of new cognitions, and independent of our

will, as well as by its content, sensation sums up for us all we

understand 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 is

these properties themselves.

What objections can be raised against my conclusion? One has evidently

the right to apply the term psychological to the whole sensation,

taken _en bloc_, and comprising in itself both impression and

consciousness. The result of this terminology will be that, as we know

nothing except sensations, the physical will remain unknowable, and

the distinction between the physical and the mental will vanish. But

it will eventually be re-established under other names by utilising

the distinction I have made between objects of cognition and acts of

cognition;--a distinction which is not verbal, and results from

observation.

What is not permissible is to declare that sensation is a

psychological phenomenon, and to oppose this phenomenon to physical

reality, as if this latter could be known to us by any other method

than 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 to

extend this interpretation to a whole series of different phenomena.

To the images, first, which proceed from sensations, since they are

recurring sensations; to the emotions also, which, according to recent

theories, result from the perception of the movements which are

produced in the heart, the vessels, and the muscles; and finally, to

effort, whether of will or of attention, which is constituted by the

muscular sensations perceived, and consequently also results from

corporeal states. The consequences must be clearly remarked. To admit

that sensation is a physical state, is to admit, by that very fact,

that the image, idea, emotion, and effort--all those manifestations

generally ascribed to the mind alone--are also physical states.

What, then, is the mind? And what share remains to it in all these

phenomena, from which it seems we are endeavouring to oust it? The

mind is in that special activity which is engaged in sensation, image,

idea, emotion, and effort. For a sensation to be produced; there must

be, as I said a little time ago, two elements: the something felt--a

tree, a house, an animal, a titillation, an odour,--and also the fact

of feeling this something, the consciousness of it, the judgment

passed on it, the reasoning applied to it--in other terms, the

categories which comprehend it. From this point of view, the dualism

contained in sensation is clearly expressed. Sensation as a thing

felt, that is, the physical part, or matter; sensation as the fact of

feeling or of judging, that is, the mind.

Mark the language I use. We say that matter is the something felt; but

we do not say for the sake of symmetry, that the mind is the something

which feels. I have used a more cautious, and, I think, a more just

formula, which places the mind in the fact of feeling. Let me repeat

again, at the risk of appearing too subtle: the mind is the act of

consciousness; it is not a subject which has consciousness. For a

subject, let it be noted, a subject which feels, is an object of

cognition--it forms part of the other group of elements, the group of

sensations. In practice we represent by mind a fragment of our own

biography, and by dint of pains we attribute to this fragment the

faculty of having a consciousness; we make it the subject of the

relation subject-object. But this fragment, being constituted of

memories and sensations, does not exactly represent the mind, and does

not correspond to our definition; it would rather represent the mind

sensationalised or materialised.

From this follows the curious consequence that the mind is endowed

with an incomplete existence; it is like form, which can only be

realised by its application to matter of some kind. One may fancy a

sensation continuing to exist, to live and to provoke movements, even

after ceasing to be perceived. Those who are not uncompromising

idealists readily admit this independence of the objects with regard

to our consciousness, but the converse is not true. It is impossible

to understand a consciousness existing without an object, a perception

without a sensation to be perceived, an attention without a point of

application, an empty wish which should have nothing to wish for; in a

word, a spiritual activity acting without matter on which to act, or

more briefly still--mind without matter. Mind and matter are

correlative terms; and, on this point, I firmly believe that Aristotle

was much closer to the truth than many modern thinkers.

I have convinced myself that the definition of mind at which we have

just arrived is, in its exactness and soberness, the only one which

permits psychology to be distinguished from the sciences nearest to

it. You know that it has been discovered in our days that there exists

a great difficulty in effecting this delimitation. The definitions of

psychology hitherto proposed nearly all have the defect of not

agreeing with the one thing defined. Time fails us to review them all,

but I shall point out one at least, because our discussion on this

particular formula will serve as a preparation for taking in hand the

last question that remains to be examined--the relation of the mind

to the body.

According to the definition I am aiming at, psychology would be the

science of internal facts, while the other sciences deal with the

external. Psychology, it has also been said, has as its instrument

introspection, while the natural sciences work with the eye, the

touch, the ear--that is to say, with the senses of extrospection.

To this distinction, I reply that in all sciences there exist but two

things: sensations and the consciousness which accompanies them. A

sensation may belong to the inner or the outer world through

accidental reasons, without any change in its nature; the sensation of

the outer world is the social sensation which we share with our

fellows. If the excitant which provokes it is included in our nervous

system, it is the sensation which becomes individual, hidden to all

except ourselves, and constituting a microcosm by the side of a

macrocosm. What importance can this have, since all the difference

depends on the position occupied by the excitant?

But we are persistently told: there are in reality two ways of

arriving 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 and

looks at the wrong side, while the natural sciences reckon, weigh,

and measure the right side. And this is so true, they add, that the

same phenomenon absolutely appears under two forms radically different

from each other according as they are looked at from one or the other

of the two points of view. Every one of our thoughts, they point out

to us, is in correlation with a particular state of our cerebral

matter; our thought is the subjective and mental face, the

corresponding cerebral process is the objective and material face.

Though this dualism is frequently presented as an observed truth, I

think it is possible to show its error. Take an example: I look at the

plain before me, and see a flock of sheep pass through it. At the same

time an observer, armed with a microscope _à la_ Jules Verne, looks

into my brain and observes there a certain molecular dance which

accompanies my visual perception. Thus, on the one hand, is my

representation; on the other, a dynamic state of the nerve cells. This

is what constitutes the right and the wrong sides of the stuff. We are

told, "See how little resemblance there is in this; a representation

is a psychical, and a movement of molecules a material, thing."

But I, on the contrary, think there is a great resemblance. When I see

the flock passing, I have a visual perception. The observer who, by

the hypothesis, is at that moment looking into my brain, also

experiences a visual perception. Granted, they are not the same

perception. How could they be the same? I am looking at the sheep, he

is looking at the interior of my brain; it is not astonishing that,

looking at objects so different, we should receive images also very

different. But, notwithstanding their difference of object--that is,

of content--there are here two visual perceptions composed in the same

way; and I do not see by what right it can be said that one represents

a material, the other a physical, phenomenon. In reality, each of

these perceptions has a two-fold and psycho-physical value--physical

in regard to the object to which it applies, and psychical inasmuch as

it is an act of perception, that is to say, of consciousness. For one

is just as much psychical as the other, and as much material, for a

flock of sheep is as material a thing as is my brain. If we keep this

conclusion in our minds, when we come to make a critical examination

of certain philosophical systems, we shall easily see the mistake they

make.

Spiritualism[51] rests on the conception that the mind can subsist and

work in total independence of any tie to matter. It is true that, in

details, spiritualists make some modification in this absolute

principle in order to explain the perceptions of the senses and the

execution of the orders of the will; but the duality, the

independence, and the autonomy of the soul and the body remain, in any

case, the peculiar dogma of the system. This dogma appears to me

utterly false; the mind cannot exist without matter to which it is

applied; and to the principle of heterogeneity, so often invoked to

forbid all commerce between the two substances, I reply by appealing

to intuition, which shows us the consciousness and its different

forms, comparison, judgment, and reasoning, so closely connected with

sensation that they cannot be imagined as existing with an isolated

life.

Materialism, we know, argues quite differently; it imagines that a

particular state of the nerve centres has the virtue of generating a

psychical phenomenon, which represents, according to various

metaphors, property, function, effect, and even secretion. Critics

have often asked how, with matter in motion, a phenomenon of thought

could be explained or fabricated. It is very probable that those who

admit this material genesis of thought, represent it to themselves

under the form of something subtle, like an electric spark, a puff of

wind, a will-of-the-wisp, or an alcoholic flame. Materialists are not

alone responsible for these inadequate metaphors, which proceed from a

metaphysics constructed of concepts. Let us recollect exactly what a

psychical phenomenon is. Let us banish the will-o'-the-wisps, replace

them by a precise instance, and return to the visual perception we

took as an example a little while back: without intending a pun,

"revenons à nos moutons." These sheep which I see in the plain are as

material, as real, as the cerebral movement which accompanies my

perception. How, then, is it possible that this cerebral movement, a

primary 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 system

to take a place within the circle of our discussion; for the same

answer will suffice for it as well as for the preceding one, and it

will 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 a

materialism perfected especially in the direction of caution. To

escape the mystery of the genesis of the mind from matter, this new

system places them parallel to each other and side by side, we might

almost say experimentally, so much do parallelists try to avoid

talking metaphysics. But their position is untenable, and they

likewise are the victims of the mirage of concepts; for they consider

the mental as capable of being parallel to the physical without

mingling with it, and of subsisting by itself and with a life of its

own. Such a hypothesis is only possible by reason of the insufficient

definition given to the mind. If it be recognised that the mind has an

incomplete existence and is only realised by its incarnation in

matter, the figure which is the basis of parallelism becomes

indefensible. There is no longer on the one hand the physical, and on

the other the mental, but on one side the physical and the mental

combined, and on the other the same combination; which amounts to

saying that the two faces to a reality, which it was thought had been

made out to be so distinct, are identical. There are not two faces,

but one face; and the monism, which certain metaphysicians struggle to

arrive at by a mysterious reconciliation of the phenomenal duality

within 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, are

to be found in several philosophers, confusedly in Berkeley, and with

more precision in M. Bergson's book on _Matière et Mémoire_. The

latter author, remarking that our brain and the outer world are to us

images of the same order, refuses to admit that the brain, which is

only a very small part of these images, can explain and contain the

other and much larger part, which comprises the vast universe. This

would amount to saying that the whole is comprised in the part. I

believe that this objection is analogous to the one just stated with

less ingenuity.

It is interesting to see how M. Bergson gets out of the difficulty

which he himself raised. Being unwilling to bring forth from the

molecular movement of the brain the representation of the world, or to

superpose the representation on this movement as in the parallelist

hypothesis, he has arrived at a theory, very ingenious but rather

obscure, which consists in placing the image of the world outside the

brain, this latter being reduced to a motor organ which executes the

orders of the mind.

We thus have four philosophical theories, which, while trying to

reconcile mind with matter, give to the representation a different

position in regard to cerebral action. The spiritualist asserts the

complete independence of the representation in relation to cerebral

movement; the materialist places it after, the parallelist by the side

of, 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 the

body, he is obliged to place our perception--that is to say, a part of

ourselves--in the objects perceived; for example, in the stars when we

are looking at them. The memory is lodged in distant planes of

consciousness which are not otherwise defined. We understand with

difficulty these emigrations, these crumblings into morsels of our

mind. This would not matter if our author did not go so far as to

maintain that the sensory nerves of the brain are not sensory nerves,

and that the severance of them does not suppress sensations, but

simply the motor efforts of these sensations. All the physiologist in

me protests against the rashness of these interpretations.

The principal difficulties of the problem of the union between the

mind and the body proceed from the two following facts, which seem

incompatible. On the one hand, our thought is conditioned by a certain

intra-cerebral movement of molecules and atoms; and, on the other

hand, this same thought has no consciousness of this molecular

movement. It does not know the path of the wave in our nerves; it does

not suspect, for example, that the image of the objects is reversed in

the retina, or that the excitements of the right eye for the most part

go into the left hemisphere. In a word, it is no anatomist. It is a

very curious thing that our consciousness enters into relation only

with the extra-cerebral, the external objects, and the superficies of

our bodies.

From this, this exact question suggests itself: a molecular wave must

come as far as our visual cerebral centre for us to have the

perception of the object before our eyes; how is it that our

consciousness is unaware of this physiological event from which it

depends, and is borne towards the distant object as if it sprang forth

outside our nervous system?

Let us first remark, that if we do not perceive this wave, yet it must

contain all we know of the external object, for it is evident that we

only know of it that part of its properties which it transmits to our

nerves and our nerve centres. All the known substance of the external

object is, then, implied in this vibration; it is there, but it is not

there by itself. The vibration is the work of two collaborators; it

expresses at once the nature of the object which provokes it, and the

nature of the nerve apparatus which transports it, as the furrow

traced in the wax of the phonograph implies the joint action of an

aërial vibration with a stylus, a cylinder, and, a clock-work

apparatus.

I therefore suppose--and this is, I say it plainly, but an

hypothesis--that if the nervous vibration so little resembles the

external excitant which generates it, it is because the factor nervous

system superadds its effect to the factor excitant. Let us imagine,

now, that we have managed to separate these two effects, and we shall

understand that then the nervous event so analysed might resemble only

the object, or only the nervous system. Now, of these two effects, one

is constant, that one which represents the action of the nervous

system; there is another which varies with each new perception, and

even with every moment of the same perception--that is to say, the

object. It is not impossible to understand that the consciousness

remains deaf to the constant and sensitive to the variable element.

There is a law of consciousness which has often been described, and

fresh applications of which are met with daily: this is, that the

consciousness only maintains itself by change, whether this change

results from the exterior by impressions received, or is produced from

the interior by movements of the attention. Let us here apply this

empirical law, and admit that it contains a first principle. It will

then be possible for us to understand that the consciousness formed

into a dialyser of the undulation may reject that constant element

which expresses the contribution of the nervous system, and may lay

bare the variable element which corresponds to the object: so that an

intestinal movement of the cerebral substance, brought to light by

this analytical consciousness, may become the perception of an object.

By accepting this hypothesis, we restore to the sensory nerves and to

the encephalic centres their property of being the substrata of

representation, and avoid the objection made above against materialism

and parallelism, that they did not explain how a cerebral movement,

which is material, can engender the perception of an object which

differs greatly from it and is yet as material as the movement

itself. There is not here, properly speaking, either generation,

transformation, or metamorphosis. The object to be perceived is

contained 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 is

the 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

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