'Origin' provided us with the working hypothesis we sought.
Moreover, it did the immense service of freeing us for ever from
the dilemma--refuse to accept the creation hypothesis, and what
have you to propose that can be accepted by any cautious
reasoner? In 1857, I had no answer ready, and I do not think
that any one else had. A year later, we reproached ourselves
with dullness for being perplexed by such an inquiry. My
reflection, when I first made myself master of the central idea
of the 'Origin,' was, "How extremely stupid not to have thought
of that!" I suppose that Columbus' companions said much the same
when he made the egg stand on end. The facts of variability, of
the struggle for existence, of adaptation to conditions, were
notorious enough; but none of us had suspected that the road to
the heart of the species problem lay through them, until Darwin
and Wallace dispelled the darkness, and the beacon-fire of the
'Origin' guided the benighted.

Whether the particular shape which the doctrine of evolution, as
applied to the organic world, took in Darwin's hands, would prove
to be final or not, was, to me, a matter of indifference. In my
earliest criticisms of the 'Origin' I ventured to point out that
its logical foundation was insecure so long as experiments in
selective breeding had not produced varieties which were more or
less infertile; and that insecurity remains up to the present
time. But, with any and every critical doubt which my sceptical
ingenuity could suggest, the Darwinian hypothesis remained
incomparably more probable than the creation hypothesis. And if
we had none of us been able to discern the paramount significance
of some of the most patent and notorious of natural facts, until
they were, so to speak, thrust under our noses, what force