In this chapter I will consider, as briefly as possible, the strongest argument that I have been able to discover against the supposition that instinct is chiefly due to habit. I have said “the strongest argument;” I should have said, the only argument that struck me as offering on the face of it serious difficulties.

Turning, then, to Mr. Darwin's chapter on instinct (“Natural Selection,” ed. 1876, p. 205), we find substantially much the same views as those taken at a later date by M. Ribot, and referred to in the preceding chapter. Mr. Darwin writes:—

“An action, which we ourselves require experience to enable us to perform, when performed by an animal, more especially a very young one, without experience, and when performed by many animals in the same way without their knowing for what purpose it is performed, is usually said to be instinctive.”

The above should strictly be, “without their being conscious of their own knowledge concerning the purpose for which they act as they do;” and though some may say that the two phrases come to the same thing, I think there is an important difference, as what I propose distinguishes ignorance from over-familiarity, both which states are alike unself-conscious, though with widely different results.