Contradiction itself, far from always being a criterion of error, is sometimes a sign of truth.

When an apprentice gets hurt, or complains of being tired, the workmen and peasants have this fine expression: "It is the trade entering his body." Each time that we have some pain to go through, we can say to ourselves quite truly that it is the universe, the order and beauty of the world, and the obedience of God that are entering our body.

Oppression that is clearly inexorable and invincible does not give rise to revolt but to submission.

There can be a true grandeur in any degree of submissiveness, because it springs from loyalty to the laws and to an oath, and not from baseness of soul.

The contradictions the mind comes up against, these are the only realities, the criterion of the real. There is no contradiction in what is imaginary. Contradiction is the test of necessity.

Nothing can have as its destination anything other than its origin. The contrary idea, the idea of progress, is poison.

Two forces rule the universe: light and gravity.