Trees and fields tell me nothing: men are my teachers.

Only the dead have seen the end of war.

Socrates said that, from above, the Earth looks like one of those twelve-patched leathern balls.

The science [geometry] is pursued for the sake of the knowledge of what eternally exists, and not of what comes for a moment into existence, and then perishes.

If one sins against the laws of proportion and gives something too big to something too small to carry it - too big sails to too small a ship, too big meals to too small a body, too big powers to too small a soul - the result is bound to be a complete upset. In an outburst of hubris the overfed body will rush into sickness, while the jack-in-office will rush into the unrighteousness that hubris always breeds.

A library of wisdom, is more precious than all wealth, and all things that are desirable cannot be compared to it. Whoever therefore claims to be zealous of truth, of happiness, of wisdom or knowledge, must become a lover of books.

All the gold which is under or upon the earth is not enough to give in exchange for virtue.