Between God and love, I recognize no mediator but my conscience.

I never was able to believe in the existence of next year except as in a metaphysical notion.

Love, supreme power of the heart, mysterious enthusiasm that encloses in itself all poetry, all heroism, all religion!

New doctrines ever displease the old. They like to fancy that the world has been losing wisdom, instead of gaining it, since they were young.

It is not enough to forgive; one must forget.

The world is the work of a single thought, expressed in a thousand different ways.

Scientific progress makes moral progress a necessity; for if man's power is increased, the checks that restrain him from abusing it must be strengthened.