"I have called this principle, by which each slight variation, if useful, is preserved, by the term Natural Selection."

"I am almost convinced that species are not (it is like confessing a murder) immutable."

"He who understands baboon would do more towards metaphysics than Locke."

"The astonishment which I felt on first seeing a party of Fuegians on a wild and broken shore will never be forgotten by me, for the reflection at once rushed into my mind—such were our ancestors."

"But I am very poorly today and very stupid and hate everybody and everything."