Creative Evolution · Henri Bergson
CHAPTER II
No doubt many secondary instincts, and also many varieties of primary instinct, admit of a scientific explanation. Yet it is doubtful whether science, with its present methods of explanation, will ever succeed in analyzing instinct completely. The reason is that instinct and intelligence are two divergent developments of one and the same principle, which in the one case remains within itself, in the other steps out of itself and becomes absorbed in the utilization of inert matter. This gradual divergence testifies to a radical incompatibility, and points to the fact that it is impossible for intelligence to reabsorb instinct. That which is instinctive in instinct cannot be expressed in terms of intelligence, nor, consequently, can it be analyzed. A man born blind, who had lived among others born blind, could not be made to believe in the possibility of perceiving a distant object without first perceiving all the objects in between. Yet vision performs this miracle. In a certain sense the blind man is right, since vision, having its origin in the stimulation of the retina, by the vibrations of the light, is nothing else, in fact, but a retinal touch. Such is indeed the _scientific_ explanation, for the function of science is just to express all perceptions in terms of touch. But we have shown elsewhere that the philosophical explanation of perception (if it may still be called an explanation) must be of another kind.[67] Now instinct also is a knowledge at a distance. It has the same relation to intelligence that vision has to touch. Science cannot do otherwise than express it in terms of intelligence; but in so doing it constructs an imitation of instinct rather than penetrates within it.
Any one can convince himself of this by studying the ingenious theories of evolutionist biology. They may be reduced to two types, which are often intermingled. One type, following the principles of neo-Darwinism, regards instinct as a sum of accidental differences preserved by selection: such and such a useful behavior, naturally adopted by the individual in virtue of an accidental predisposition of the germ, has been transmitted from germ to germ, waiting for chance to add fresh improvements to it by the same method. The other type regards instinct as lapsed intelligence: the action, found useful by the species or by certain of its representatives, is supposed to have engendered a habit, which, by hereditary transmission, has become an instinct. Of these two types of theory, the first has the advantage of being able to bring in hereditary transmission without raising grave objection; for the accidental modification which it places at the origin of the instinct is not supposed to have been acquired by the individual, but to have been inherent in the germ. But, on the other hand, it is absolutely incapable of explaining instincts as sagacious as those of most insects.
These instincts surely could not have attained, all at once, their present degree of complexity; they have probably evolved; but, in a hypothesis like that of the neo-Darwinians, the evolution of instinct could have come to pass only by the progressive addition of new pieces which, in some way, by happy accidents, came to fit into the old. Now it is evident that, in most cases, instinct could not have perfected itself by simple accretion: each new piece really requires, if all is not to be spoiled, a complete recasting of the whole. How could mere chance work a recasting of the kind? I agree that an accidental modification of the germ may be passed on hereditarily, and may somehow wait for fresh accidental modifications to come and complicate it. I agree also that natural selection may eliminate all those of the more complicated forms of instinct that are not fit to survive. Still, in order that the life of the instinct may evolve, complications fit to survive have to be produced. Now they will be produced only if, in certain cases, the addition of a new element brings about the correlative change of all the old elements. No one will maintain that chance could perform such a miracle: in one form or another we shall appeal to intelligence.
We shall suppose that it is by an effort, more or less conscious, that the living being develops a higher instinct. But then we shall have to admit that an acquired habit can become hereditary, and that it does so regularly enough to ensure an evolution. The thing is doubtful, to put it mildly. Even if we could refer the instincts of animals to habits intelligently acquired and hereditarily transmitted, it is not clear how this sort of explanation could be extended to the vegetable world, where effort is never intelligent, even supposing it is sometimes conscious. And yet, when we see with what sureness and precision climbing plants use their tendrils, what marvelously combined manoeuvres the orchids perform to procure their fertilization by means of insects,[68] how can we help thinking that these are so many instincts? This is not saying that the theory of the neo-Darwinians must be altogether rejected, any more than that of the neo-Lamarckians. The first are probably right in holding that evolution takes place from germ to germ rather than from individual to individual; the second are right in saying that at the origin of instinct there is an effort (although it is something quite different, we believe, from an _intelligent_ effort). But the former are probably wrong when they make the evolution of instinct an _accidental_ evolution, and the latter when they regard the effort from which instinct proceeds as an _individual_ effort. The effort by which a species modifies its instinct, and modifies itself as well, must be a much deeper thing, dependent solely neither on circumstances nor on individuals. It is not purely accidental, although accident has a large place in it; and it does not depend solely on the initiative of individuals, although individuals collaborate in it.
Compare the different forms of the same instinct in different species of hymenoptera. The impression derived is not always that of an increasing complexity made of elements that have been added together one after the other. Nor does it suggest the idea of steps up a ladder. Rather do we think, in many cases at least, of the circumference of a circle, from different points of which these different varieties have started, all facing the same centre, all making an effort in that direction, but each approaching it only to the extent of its means, and to the extent also to which this central point has been illumined for it. In other words, instinct is everywhere complete, but it is more or less simplified, and, above all, simplified _differently_. On the other hand, in cases where we do get the impression of an ascending scale, as if one and the same instinct had gone on complicating itself more and more in one direction and along a straight line, the species which are thus arranged by their instincts into a linear series are by no means always akin.
Thus, the comparative study, in recent years, of the social instinct in the different apidae proves that the instinct of the meliponines is intermediary in complexity between the still rudimentary tendency of the humble bees and the consummate science of the true bees; yet there can be no kinship between the bees and the meliponines.[69] Most likely, the degree of complexity of these different societies has nothing to do with any greater or smaller number of added elements. We seem rather to be before a _musical theme_, which had first been transposed, the theme as a whole, into a certain number of tones and on which, still the whole theme, different variations had been played, some very simple, others very skilful. As to the original theme, it is everywhere and nowhere. It is in vain that we try to express it in terms of any idea: it must have been, originally, _felt_ rather than _thought_. We get the same impression before the paralyzing instinct of certain wasps. We know that the different species of hymenoptera that have this paralyzing instinct lay their eggs in spiders, beetles or caterpillars, which, having first been subjected by the wasp to a skilful surgical operation, will go on living motionless a certain number of days, and thus provide the larvae with fresh meat.
In the sting which they give to the nerve-centres of their victim, in order to destroy its power of moving without killing it, these different species of hymenoptera take into account, so to speak, the different species of prey they respectively attack. The Scolia, which attacks a larva of the rose-beetle, stings it in one point only, but in this point the motor ganglia are concentrated, and those ganglia alone: the stinging of other ganglia might cause death and putrefaction, which it must avoid.[70] The yellow-winged Sphex, which has chosen the cricket for its victim, knows that the cricket has three nerve-centres which serve its three pairs of legs--or at least it acts as if it knew this. It stings the insect first under the neck, then behind the prothorax, and then where the thorax joins the abdomen.[71] The Ammophila Hirsuta gives nine successive strokes of its sting upon nine nerve-centres of its caterpillar, and then seizes the head and squeezes it in its mandibles, enough to cause paralysis without death.[72] The general theme is "the necessity of paralyzing without killing"; the variations are subordinated to the structure of the victim on which they are played. No doubt the operation is not always perfect.
It has recently been shown that the Ammophila sometimes kills the caterpillar instead of paralyzing it, that sometimes also it paralyzes it incompletely.[73] But, because instinct is, like intelligence, fallible, because it also shows individual deviations, it does not at all follow that the instinct of the Ammophila has been acquired, as has been claimed, by tentative intelligent experiments. Even supposing that the Ammophila has come in course of time to recognize, one after another, by tentative experiment, the points of its victim which must be stung to render it motionless, and also the special treatment that must be inflicted on the head to bring about paralysis without death, how can we imagine that elements so special of a knowledge so precise have been regularly transmitted, one by one, by heredity? If, in all our present experience, there were a single indisputable example of a transmission of this kind, the inheritance of acquired characters would be questioned by no one. As a matter of fact, the hereditary transmission of a contracted habit is effected in an irregular and far from precise manner, supposing it is ever really effected at all.
But the whole difficulty comes from our desire to express the knowledge of the hymenoptera in terms of intelligence. It is this that compels us to compare the Ammophila with the entomologist, who knows the caterpillar as he knows everything else--from the outside, and without having on his part a special or vital interest. The Ammophila, we imagine, must learn, one by one, like the entomologist, the positions of the nerve-centres of the caterpillar--must acquire at least the practical knowledge of these positions by trying the effects of its sting. But there is no need for such a view if we suppose a _sympathy_ (in the etymological sense of the word) between the Ammophila and its victim, which teaches it from within, so to say, concerning the vulnerability of the caterpillar. This feeling of vulnerability might owe nothing to outward perception, but result from the mere presence together of the Ammophila and the caterpillar, considered no longer as two organisms, but as two activities. It would express, in a concrete form, the _relation_ of the one to the other. Certainly, a scientific theory cannot appeal to considerations of this kind. It must not put action before organization, sympathy before perception and knowledge. But, once more, either philosophy has nothing to see here, or its rôle begins where that of science ends.
Whether it makes instinct a "compound reflex," or a habit formed intelligently that has become automatism, or a sum of small accidental advantages accumulated and fixed by selection, in every case science claims to resolve instinct completely either into _intelligent_ actions, or into mechanisms built up piece by piece like those combined by our _intelligence_. I agree indeed that science is here within its function. It gives us, in default of a real analysis of the object, a translation of this object in terms of intelligence. But is it not plain that science itself invites philosophy to consider things in another way? If our biology was still that of Aristotle, if it regarded the series of living beings as unilinear, if it showed us the whole of life evolving towards intelligence and passing, to that end, through sensibility and instinct, we should be right, we, the intelligent beings, in turning back towards the earlier and consequently inferior manifestations of life and in claiming to fit them, without deforming them, into the molds of our understanding. But one of the clearest results of biology has been to show that evolution has taken place along divergent lines. It is at the extremity of two of these lines--the two principal--that we find intelligence and instinct in forms almost pure.
Why, then, should instinct be resolvable into intelligent elements? Why, even, into terms entirely intelligible? Is it not obvious that to think here of the intelligent, or of the absolutely intelligible, is to go back to the Aristotelian theory of nature? No doubt it is better to go back to that than to stop short before instinct as before an unfathomable mystery. But, though instinct is not within the domain of intelligence, it is not situated beyond the limits of mind. In the phenomena of feeling, in unreflecting sympathy and antipathy, we experience in ourselves--though under a much vaguer form, and one too much penetrated with intelligence--something of what must happen in the consciousness of an insect acting by instinct. Evolution does but sunder, in order to develop them to the end, elements which, at their origin, interpenetrated each other. More precisely, intelligence is, before anything else, the faculty of relating one point of space to another, one material object to another; it applies to all things, but remains outside them; and of a deep cause it perceives only the effects spread out side by side. Whatever be the force that is at work in the genesis of the nervous system of the caterpillar, to our eyes and our intelligence it is only a juxtaposition of nerves and nervous centres.
Instinct is sympathy. If this sympathy could extend its object and also reflect upon itself, it would give us the key to vital operations--just as intelligence, developed and disciplined, guides us into matter. For--we cannot too often repeat it--intelligence and instinct are turned in opposite directions, the former towards inert matter, the latter towards life. Intelligence, by means of science, which is its work, will deliver up to us more and more completely the secret of physical operations; of life it brings us, and moreover only claims to bring us, a translation in terms of inertia. It goes all round life, taking from outside the greatest possible number of views of it, drawing it into itself instead of entering into it. But it is to the very inwardness of life that _intuition_ leads us--by intuition I mean instinct that has become disinterested, self-conscious, capable of reflecting upon its object and of enlarging it indefinitely.
That an effort of this kind is not impossible, is proved by the existence in man of an aesthetic faculty along with normal perception. Our eye perceives the features of the living being, merely as assembled, not as mutually organized. The intention of life, the simple movement that runs through the lines, that binds them together and gives them significance, escapes it. This intention is just what the artist tries to regain, in placing himself back within the object by a kind of sympathy, in breaking down, by an effort of intuition, the barrier that space puts up between him and his model. It is true that this aesthetic intuition, like external perception, only attains the individual. But we can conceive an inquiry turned in the same direction as art, which would take life _in general_ for its object, just as physical science, in following to the end the direction pointed out by external perception, prolongs the individual facts into general laws. No doubt this philosophy will never obtain a knowledge of its object comparable to that which science has of its own. Intelligence remains the luminous nucleus around which instinct, even enlarged and purified into intuition, forms only a vague nebulosity.
But, in default of knowledge properly so called, reserved to pure intelligence, intuition may enable us to grasp what it is that intelligence fails to give us, and indicate the means of supplementing it. On the one hand, it will utilize the mechanism of intelligence itself to show how intellectual molds cease to be strictly applicable; and on the other hand, by its own work, it will suggest to us the vague feeling, if nothing more, of what must take the place of intellectual molds. Thus, intuition may bring the intellect to recognize that life does not quite go into the category of the many nor yet into that of the one; that neither mechanical causality nor finality can give a sufficient interpretation of the vital process. Then, by the sympathetic communication which it establishes between us and the rest of the living, by the expansion of our consciousness which it brings about, it introduces us into life's own domain, which is reciprocal interpenetration, endlessly continued creation. But, though it thereby transcends intelligence, it is from intelligence that has come the push that has made it rise to the point it has reached. Without intelligence, it would have remained in the form of instinct, riveted to the special object of its practical interest, and turned outward by it into movements of locomotion.
How theory of knowledge must take account of these two faculties, intellect and intuition, and how also, for want of establishing a sufficiently clear distinction between them, it becomes involved in inextricable difficulties, creating phantoms of ideas to which there cling phantoms of problems, we shall endeavor to show a little further on. We shall see that the problem of knowledge, from this point of view, is one with the metaphysical problem, and that both one and the other depend upon experience. On the one hand, indeed, if intelligence is charged with matter and instinct with life, we must squeeze them both in order to get the double essence from them; metaphysics is therefore dependent upon theory of knowledge. But, on the other hand, if consciousness has thus split up into intuition and intelligence, it is because of the need it had to apply itself to matter at the same time as it had to follow the stream of life. The double form of consciousness is then due to the double form of the real, and theory of knowledge must be dependent upon metaphysics. In fact, each of these two lines of thought leads to the other; they form a circle, and there can be no other centre to the circle but the empirical study of evolution. It is only in seeing consciousness run through matter, lose itself there and find itself there again, divide and reconstitute itself, that we shall form an idea of the mutual opposition of the two terms, as also, perhaps, of their common origin. But, on the other hand, by dwelling on this opposition of the two elements and on this identity of origin, perhaps we shall bring out more clearly the meaning of evolution itself.
Such will be the aim of our next chapter. But the facts that we have just noticed must have already suggested to us the idea that life is connected either with consciousness or with something that resembles it. Throughout the whole extent of the animal kingdom, we have said, consciousness seems proportionate to the living being's power of choice. It lights up the zone of potentialities that surrounds the act. It fills the interval between what is done and what might be done. Looked at from without, we may regard it as a simple aid to action, a light that action kindles, a momentary spark flying up from the friction of real action against possible actions. But we must also point out that things would go on in just the same way if consciousness, instead of being the effect, were the cause. We might suppose that consciousness, even in the most rudimentary animal, covers by right an enormous field, but is compressed in fact in a kind of vise: each advance of the nervous centres, by giving the organism a choice between a larger number of actions, calls forth the potentialities that are capable of surrounding the real, thus opening the vise wider and allowing consciousness to pass more freely.
In this second hypothesis, as in the first, consciousness is still the instrument of action; but it is even more true to say that action is the instrument of consciousness; for the complicating of action with action, and the opposing of action to action, are for the imprisoned consciousness the only possible means to set itself free. How, then, shall we choose between the two hypotheses? If the first is true, consciousness must express exactly, at each instant, the state of the brain; there is strict parallelism (so far as intelligible) between the psychical and the cerebral state. On the second hypothesis, on the contrary, there is indeed solidarity and interdependence between the brain and consciousness, but not parallelism: the more complicated the brain becomes, thus giving the organism greater choice of possible actions, the more does consciousness outrun its physical concomitant.
Thus, the recollection of the same spectacle probably modifies in the same way a dog's brain and a man's brain, if the perception has been the same; yet the recollection must be very different in the man's consciousness from what it is in the dog's. In the dog, the recollection remains the captive of perception; it is brought back to consciousness only when an analogous perception recalls it by reproducing the same spectacle, and then it is manifested by the recognition, _acted_ rather than _thought_, of the present perception much more than by an actual reappearance of the recollection itself. Man, on the contrary, is capable of calling up the recollection at will, at any moment, independently of the present perception. He is not limited to _playing_ his past life again; he _represents_ and _dreams_ it. The local modification of the brain to which the recollection is attached being the same in each case, the psychological difference between the two recollections cannot have its ground in a particular difference of detail between the two cerebral mechanisms, but in the difference between the two brains taken each as a whole.
The more complex of the two, in putting a greater number of mechanisms in opposition to one another, has enabled consciousness to disengage itself from the restraint of one and all and to reach independence. That things do happen in this way, that the second of the two hypotheses is that which must be chosen, is what we have tried to prove, in a former work, by the study of facts that best bring into relief the relation of the conscious state to the cerebral state, the facts of normal and pathological recognition, in particular the forms of aphasia.[75] But it could have been proved by pure reasoning, before even it was evidenced by facts. We have shown on what self-contradictory postulate, on what confusion of two mutually incompatible symbolisms, the hypothesis of equivalence between the cerebral state and the psychic state rests.[76]
Ideas discussed in this chapter
Text from Project Gutenberg, public domain in the United States.