Chapter II

There is another way of knowing, at once more elementary, more intimate, and more uncertain. This is absorption. The elements of our nourishment, in proportion as we "know" them, disintegrate, yield soluble parts to our organism, and reject the rest in a form equally unknowable. If we reject, as we should, the primitive distinction between soul and body, admitting only the body and believing everything to be physical, then this way of knowing should be studied parallel with those ways which spring from each of our different senses, or from their collaboration. It is certain that absorption has taught man in every age. It is through it, and not by virtue of an unknown instinct, that he has succeeded in separating vegetables and animals into good and bad, into useful and harmful or indifferent. Our analytical methods are still unable, save perhaps in particularly expert hands, to distinguish mushrooms as a harmful or favourable form of nourishment. The expert himself must be guided, for this delicate operation, by a direct and real experiment of absorption. Man, devoid of science, took himself as laboratory. None was surer. He acquired, by this means, certain parts of his knowledge which have proved most useful to humanity and to the domestic animals. From time to time medications are rediscovered which figure in ancient pharmacopeias. Thus formate of lime or of soda, recently prescribed as a muscular invigorant, contains scarcely a principle that did not figure in the old "water of magnanimity," obtained by maceration and distillation of a certain quantity of ants. How did our ancestors, who were no doubt shepherds and labourers, come to distinguish the virtue of ants? Evidently by eating them. The foul Arabs and other low forms of humanity who eat their vermin, find in them, perhaps, an analogous tonic. This practice, like all those which resolve themselves into absorption, is assuredly dictated by experience. Neither a man nor an animal can, in principle, become addicted to an act which is harmful to him. Between acts that are harmful, and acts that are salutary, there is a whole series of games, but it is difficult to admit that a daily game is a harmful act.

Why do not peasants eat certain abundant rodents? It is easy to answer by offering taste and disgust as pretexts; but this is reversing the logical order of the terms of the argument.

A food does not disgust by its odour. The odour of a food disgusts because this food is harmful or useless. To understand this, without the necessity of insisting upon it, it is enough to think of all those foods with nauseous odours, which we appreciate much more than those which might be considered pleasant. Such is the fruit of experience, that is to say, of knowledge.

I believe that absorption should be considered one of the best means we have of appreciating the practical value of certain parts of the external world. Agriculture, kitchen-gardening, cooking, pharmacy almost entirely, are born of it. Assuredly men, even the rarest chemists and physiologists, could suck a kola-nut for years, without suspecting those virtues that savages found quite simply by cracking it with their teeth.

They jest who, ignoring not only the importance but the very existence of this sixth or seventh or tenth sense, attribute to taste or to smell a mysterious power of divining the harmfulness of a plant or of its fruit. How can they help seeing immediately that this preservative instinct, if it be hereditary, has had a beginning, and that, at this beginning, there was a fact of knowledge? The traditional notion of instinct must be left in the old theological and spiritualistic repertories. It serves simple people as an easy means of distinguishing man from the animals. Animals have instinct, man has intelligence. There are proofs. Man poisons himself with mushrooms, frugivorous animals never. What man? Not the traditional peasant surely. Only the _déraciné_ or the city-dweller, who has naturally lost an instinct which was useless to him. This proof proves only that it is dangerous for man, as for the other animals, or for plaints themselves, to change their habitat. There is a painful, uncertain transitory phase. It is during this phase that we go into the woods, picknicking, and gather toadstools. But rabbits in cages, when given wet grass or vegetables instinctively unknown to them, allow themselves to be completely poisoned. Free, it would never have occurred to them to crop at dewfall, because their ancestors, dwelling in extremely thick woodlands, were ignorant of the very existence of the dew, and transmitted distrust of wet grass to their offspring.

Man, even in the state of semi-civilization, is burdened with too much knowledge for it all to be transmitted hereditarily; but there is no doubt that the oldest and most useful reaches us in this manner. When we walk in the forest there are berries that tempt us, whortleberries, for example, but never alderberries. Who has taught us (I am supposing a real ignorance), that they are purgative and even dangerous? Instinct? What is instinct? The hereditary transmission of knowledge.

This transmission can, without doubt, occur in the case of abstract ideas, as well as of practical ideas--that is to say, useful for the conservation of life. Some, besides, are really useful, and even primordial. It is as reasonable to believe that they are inherited as to suppose them personally acquired. It might be possible to rehabilitate the theory of innate ideas, by revising it carefully and eliminating from its catalogue all sorts of Platonic or Christian inventions, too recent to have entered our blood.

As to the direct knowledge of ideas, this is gained in a form sensibly analogous to the knowledge of matter by absorption. Once they have entered us, ideas either remain inert, unknown, or else are disintegrated. In the first case, it is not long before they are expelled from the brain, much like an indigestible morsel which has entered the intestines. Their stay may produce a certain irritation, even lesions. That is to say, it may provoke absurd acts, manifestly without logical relation to the normal physiology of the patient. This effect may be observed in all countries, but especially in France, at the time of great political or moral crises. We see people tormented by the presence of a parasitic idea in their brain, like sheep by the residence of a trumpet-fly's egg in their frontal sinus. Man, like the sheep, has the "itch." That ends badly for the sheep--for the man also, very often.

In the second case, the external ideas that have entered the brain are disintegrated there and unite their atoms with the other atomic knowledge already within us. An idea is digested, assimilated. Assimilated, it then becomes very different from what it was when it entered the intelligence. Like intestinal absorption, mental absorption is, therefore, an excellent though indirect way of acquiring knowledge. In both cases, the ideas, like the aliments, will be known, not immediately, but by their effects. Thus men know hereditarily that certain ideas are individual or social poisons, and that others are equally favourable to the welfare of the individual or to the development of a people. But, in this order, notions of utility and of harmfulness are much less precise. We have seen a certain idea, reputed to be very dangerous, contributing to the health of a man, of a family, of a society, of civilization itself. Ideas are extremely workable, plastic. They take the shape of the brain. There are perhaps no ideas that are bad for a healthy brain whose form is normal. There are perhaps no good ones for a brain that is sick and warped.