What light is to the eyes - what air is to the lungs - what love is to the heart, liberty is to the soul of man.

Liberty a word without which all other words are vain.

I love to think of the whole universe together as one eternal fact. I love to think that everything is alive; that crystallization is itself a step toward joy. I love to think that when a bud bursts into blossom: it feels a thrill. I love to have the universe full of feeling and full of joy, and not full of simple dead, inert matter, managed by an old bachelor for all eternity.

Heresy is a cradle; orthodoxy a coffin.

Diderot took the ground that, if orthodox religion be true Christ was guilty of suicide. Having the power to defend himself he should have used it.

The present is the necessary product of all the past, the necessary cause of all the future.

I found that the clergy did not understand their own book.