Darwin has done more to change human thought than all the priests who have existed.

There is no evidence that God ever interfered in the affairs of man. The hand of earth is stretched uselessly towards heaven. From the clouds there comes no help.

We have at last ascertained that miracles can be perfectly understood; that there is nothing mysterious about them; that they are simply transparent falsehoods.

It seems to me impossible for a civilized man to love or worship, or respect the God of the Old Testament. A really civilized man, a really civilized woman, must hold such a God in abhorrence and contempt... In the New Testament, death is not the end, but the beginning of punishment that has no end. In the New Testament the malice of God is infinite and the hunger of his revenge eternal... This frightful dogma, this infinite lie, made me the implacable enemy of Christianity. The truth is that this belief in eternal pain has been the real persecutor.

I am not so much for the freedom of religion as I am for the religion of freedom.

The man who does not do his own thinking is a slave, and is a traitor to himself and to his fellow-men.

Ignorance is the worst form of slavery. (Paraphrased)