ng 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.
It is true that we thus get the whole outer effect of it. The Ammophila,
no doubt, discerns but a very little of that force, just what concerns
itself; but at least it discerns it from within, quite otherwise than by
a process of knowledge--by an intuition (_lived_ rather than
_represented_), which is probably like what we call divining sympathy.

A very significant fact is the swing to and fro of scientific theories
of instinct, from regarding it as intelligent to regarding it as simply
intelligible, or, shall I say, between likening it to an intelligence
"lapsed" and reducing it to a pure mechanism.[74] Each of these systems
of explanation triumphs in its criticism of the other, the first when it
shows us that instinct cannot be a mere reflex, the other when it
declares that instinct is something different from intelligence, even
fallen into unconsciousness. What can this mean but that they are two
symbolisms, equally acceptable in certain respects, and, in other
respects, equally i