Understanding is the beginning of approving.

No theory is good unless it permits, not rest, but the greatest work. No theory is good except on condition that one use it to go on beyond.

The most decisive actions of life are most often unconsidered actions.

What thwarts us and demands of us the greatest effort is also what can teach us most.

The loveliest creations of men are persistently painful. What would be the description of happiness? Nothing, except what prepares and then what destroys it.

If one could recover the uncompromising spirit of one's youth, one's greatest indignation would be for what one has become.

Wisdom comes not from reason but from love.