What life half gives a man, posterity gives entirely.

When you take a man as he is, you make him worse. When you take a man as he can be, you make him better.

Nature knows no pause in progress and development, and attaches her curse on all inaction.

Normally, the sciences distance themselves from life and the return to it via a detour.

It seems to me that every phenomenon, every fact, itself is the really interesting object. Whoever explains it, or connects it with other events, usually only amuses himself or makes sport of us, as, for instance, the naturalist or historian. But a single action or event is interesting, not because it is explainable, but because it is true.

If a man writes a book, let him set down only what he knows. I have guesses enough of my own.

What we do not understand we do not possess.