Thought is a kind of opium; it can intoxicate us, while still broad awake; it can make transparent the mountains and everything that exists.

A man only understands what is akin to something already existing in himself.

Philosophy means the complete liberty of the mind, and therefore independence of all social, political or religious prejudice... It loves one thing only... truth.

Any landscape is a condition of the spirit.

To repel one's cross is to make it heavier.

A man without passion is only a latent force, only a possibility, like a stone waiting for the blow from the iron to give forth sparks.

Knowledge, love, power-there is the complete life.