Not the intensity but the duration of high feelings makes high men.

The noble man honours in himself the powerful one, him also who has power over himself, who knows how to speak and how to keep silence, who takes pleasure in subjecting himself to severity and hardness, and has reverence for all that is severe and hard.

He who has always spared himself much will in the end become sickly of so much consideration. Praised be what hardens!

One must know how to conserve oneself- the best test of independence.

A book calls for pen, ink, and a writing desk; today the rule is that pen, ink, and a writing desk call for a book.

Time, space, and causality are only metaphors of knowledge, with which we explain things to ourselves.

Moral sensibilities are nowadays at such cross-purposes that to one man a morality is proved by its utility, while to another its utility refutes it.