It is one of Mr. Darwin's many great services to Biological science that
he has demonstrated the significance of these facts. He has shown
that--given variation and given change of conditions--the inevitable
result is the exercise of such an influence upon organisms that one is
helped and another is impeded; one tends to predominate, another to
disappear; and thus the living world bears within itself, and is
surrounded by, impulses towards incessant change.

But the truths just stated are as certain as any other physical laws,
quite independently of the truth, or falsehood, of the hypothesis which
Mr. Darwin has based upon them; and that M. Flourens, missing the
substance and grasping at a shadow, should be blind to the admirable
exposition of them, which Mr. Darwin has given, and see nothing there
but a "derniere erreur du dernier siecle "--a personification of
Nature--leads us indeed to cry with him: "O lucidite! O solidite de
l'esprit Francais, que devenez-vous?"

M. Flourens has, in fact, utterly failed to comprehend the first
principles of the doctrine which he assails so rudely. His objections
to details are of the old sort, so battered and hackneyed on this side
of the Channel, that not even a Quarterly Reviewer could be induced to
pick them up for the purpose of pelting Mr. Darwin over again. We have
Cuvier and the mummies; M. Roulin and the domesticated animals of
America; the difficulties presented by hybridism and by Palaeontology;
Darwinism a 'rifacciamento' of De Maillet and Lamarck; Darwinism a
system without a commencement, and its author bound to believe in M.
Pouchet, etc. etc. How one knows it all by heart, and with what relief
one reads at p. 65--