"False facts are highly injurious to the progress of science, for they often endure long; but false views, if supported by some evidence, do little harm, for every one takes a salutary pleasure in prov…"

"A man who dares to waste one hour of time has not discovered the value of life."

"Man has risen to the very summit of the organic scale; and the fact of his having thus risen, instead of having been aboriginally placed there, is the best proof of his power of development."

"It is not the strongest of the species that survives, nor the most intelligent, but the one most responsive to change."

"I have no great quickness of apprehension or wit which is so remarkable in some clever men."