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.