special reference to man; while, on the other
hand, it is equally impossible to point to one which does not refer to
the welfare of the animal presenting it. Indeed, when the point is
suggested, it seems to me surprising how few in number are the instincts
of animals which have proved to be so much as of secondary or accidental
benefit to man, in the same way as skins, furs, and a whole host of
other animal products are thus of secondary use to him. Therefore, this
writer not only failed to perceive the most obvious truth that every
instinct, without any single exception, has reference to the animal
which presents it; but he also conceived a purely fictitious inversion
of this truth, and wrote an essay to prove a statement which all the
instincts in the animal kingdom unite in contradicting.

This example will serve to show, in a striking manner, not only the
distance that we have travelled in our interpretation of organic nature
between two successive editions of the _Encyclopaedia Britannica_, but
also the amount of verification which this fact furnishes to the theory
of natural selection. For, inasmuch as it belongs to the very essence of
this theory that all adaptive characters (whether instinctive or
structural) must have reference to their own possessors, we find
overpowering verification furnished to the theory by the fact now before
us--namely, that immediately prior to the enunciation of this theory,
the truth that all adaptive characters have reference only to the
species which present them was not perceived. In other words, it was the
testing of this theory by the facts of nature that _revealed_ to
naturalists the general law which the theory, as it were, predicted--the
general law that all adaptive characters have primary reference to the
species which present them. And when we remember that this is a kind of
verification which is furnished by millions of separate cases, the whole
mass of it taken together is, as I have before said, overwhelming.

It is somewhat remarkable that the enormous importance of this argument
in favour of natural selection as a prime factor of organic evolution
has not received the attention which it deserves. Even Darwin himself,
with his characteristic reserve, has not presented its incalculable
significance; nor do I know any of his followers who have made any
approach to an adequate use of it in their advocacy of his views. In
preparing the present chapter, therefore, I have bee