that I understand what he wishes
to imply by the word "means." I do not see how the fact that those
animals which are best fitted for the conditions of their existence
commonly survive in the struggle for life, can be called in any special
sense a "means" of modification.

"Means" is a dangerous word; it slips too easily into "cause." We have
seen Mr. Darwin himself say that Buffon did not enter on "the _causes or
means_"[347] of modification, as though these two words were synonymous,
or nearly so. Nevertheless, the use of the word "means" here enables Mr.
Darwin to speak of Natural Selection as if it were an active cause
(which he constantly does), and yet to avoid expressly maintaining that
it is a cause of modification. This, indeed, he has not done in express
terms, but he does it by implication when he writes, "Natural Selection
_might be most effective in giving_ the proper colour to each kind of
grouse, and in _keeping_ that colour when once acquired." Such language,
says the late Mr. G. H. Lewes, "is misleading;" it makes "selection an
agent."[348]

It is plain that natural selection cannot be considered a cause of
variation; and if not of variation, which is as the rain drop, then not
of specific and generic modification, which are as the river; for the
variations must make their appearance before they can be selected.
Suppose that it is an advantage to a horse to have an especially hard
and broad hoof, then a horse born with such a hoof will indeed probably
survive in the struggle for existence, but he was not born with the
larger and harder hoof _because of his subsequently surviving_. He
survived because he was born fit--not, he was born fit because he
survived. The variation must arise first and be preserved afterwards.

Mr. Darwin therefore is in the following dilemma. If he does not treat
natural selection as a cause of variation, the 'Origin of Species' will
turn out to have no _raison d'etre_. It will have professed to have
explained to us the manner in which species has originated, but it will
have left us in the dark concerning the origin of those variations
which, when added together, amount to specific and generic differences.
Thus, as I said in 'Life and Habit,' Mr. Darwin will have made us think
we know the whole road, in spite of his having almost ostentatiously
blindfolded us at every step in the journey. The 'Origin of Species'
would thus prove to be no less a piece of intellectual sleight-