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

"If a man were to read a book on the cultivation of fruit trees, and then attempt to practice it without having seen a single tree, he would not be more unsuccessful than those who attempt to philosoph…"

"I have gradually come to disbelieve in Christianity as a divine revelation."

"Man is descended from a hairy, tailed quadruped, probably arboreal in its habits, and an inhabitant of the Old World."

"The more I see of the world, the more I am convinced of the fact that it is full of wonders."