The wise man belongs to all countries, for the home of a great soul is the whole world.
Do not trust all men, but trust men of worth; the former course is silly, the latter a mark of prudence.
No power and no treasure can outweigh the extension of our knowledge.
It is hard to fight desire; but to control it is the sign of a reasonable man.
I would rather discover one true cause than gain the kingdom of Persia.
Nothing exists but atoms and the void.