I shall always feel respect for every one who has written a book, let it be what it may, for I had no idea of the trouble which trying to write common English could cost one—And alas there yet remains the worst part of all correcting the press.

I would give absolutely nothing for the theory of Natural Selection, if it requires miraculous additions at any one stage of descent.

We behold the face of nature bright with gladness.

I am not very sceptical, — a frame of mind which I believe to be injurious to the progress of science. A good deal of scepticism in a scientific man is advisable to avoid much loss of time, but I have met with not a few men, who, I feel sure, have often thus been deterred from experiment or observations, which would have proved directly or indirectly serviceable .

Extinction has only separated groups: it has by no means made them; for if every form which has ever lived on this earth were suddenly to reappear, though it would be quite impossible to give definitions by which each group could be distinguished from other groups, as all would blend together by steps as fine as those between the finest existing varieties, nevertheless a natural classification, or at least a natural arrangement, would be possible.

Why, if species have descended from other species by insensibly fine gradations, do we not everywhere see innumerable transitional forms.

... not one living species will transmit its unaltered likeness to a distant futurity.