How can we learn self-knowledge? Never by taking thought but rather by action. Try to do your duty and you'll soon discover what you're like.

Everything we do has a result. But that which is right and prudent does not always lead to good, nor the contrary to what is bad.

Never by reflection, but only by doing is self- knowledge possible to one.

The thinking person has the strange characteristic to like to create a fantasy in the place of the unsolved problem, a fantasy that stays with the person even when the problem has been solved and truth made its appearance.

With knowledge grows doubt.

Progress has not followed a straight ascending line, but a spiral with rhythms of progress and retrogression, of evolution and dissolution.

Chess is the touchstone of intellect.