Disbelief crept over me at a very slow rate, but at last it was complete.

The instruction at Edinburgh was altogether by lectures, and these were intolerably dull, with the exception of those on chemistry.

After five years' work I allowed myself to speculate on the subject, and drew up some short notes; these I enlarged in 1844 into a sketch of the conclusions, which then seemed to me probable: from that period to the present day I have steadily pursued the same object. I hope that I may be excused for entering on these personal details, as I give them to show that I have not been hasty in coming to a decision.‎

I have called this principle, by which each slight variation, if useful, is preserved, by the term Natural Selection, in order to mark its relation to man's power of selection. But the expression often used by Mr. Herbert Spencer of the Survival of the Fittest is more accurate, and is sometimes equally convenient.

Man is developed from an ovule, about 125th of an inch in diameter, which differs in no respect from the ovules of other animals.

I have been speculating last night what makes a man a discoverer of undiscovered things. As far as I can conjecture the art consists in habitually searching for the causes and meaning of everything which occurs.

About thirty years ago there was much talk that geologists ought only to observe and not theorise; and I well remember some one saying that at this rate a man might as well go into a gravel-pit and count the pebbles and describe the colours. How odd it is that anyone should not see that all observation must be for or against some view if it is to be of any service!