I don't know a greater advantage, than to appreciate the worth of an enemy.

All men would be masters of others, and no man is lord of himself.

No two men see the world exactly alike, and different temperaments will apply in different ways a principle that they both acknowledge.

Whoever aspiring, struggles on, for him there is salvation.

The history of science is science itself; the history of the individual, the individual.

Rejoice that you have still have a long time to live, before the thought comes to you that there is nothing more in the world to see.

The master proves himselin recognizing his limitations.