It is the courage to make a clean breast of it in the face of every question that makes the philosopher. He must be like Sophocles' Oedipus, who, seeking enlightenment concerning his terrible fate, pursues his indefatigable inquiry even though he divines that appalling horror awaits him in the answer. But most of us carry with us the Jocasta in our hearts, who begs Oedipus, for God's sake, not to inquire further.

Night gives a black look to everything, whatever it may be.

Intellect is a magnitude of intensity, not a magnitude of extensity.

The man never feels the want of what it never occurs to him to ask for.

To expect a man to retain everything that he has ever read is like expecting him to carry about in his body everything that he has ever eaten.

The principle of contradiction establishes merely the agreement of concepts, but does not itself produce concepts.

Religion is the metaphysics of the masses.