I want no heaven for which I must give my reason; no happiness in exchange for my liberty, and no immortality that demands the surrender of my individuality. Better rot in the windowless tomb, to which there is no door but the red mouth of the pallid worm, than to wear the jeweled collar of a god.

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

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

The glory of science is, that it is freeing the soul, breaking the mental manacles, getting the brain out of bondage, giving courage to thought, filling the world with mercy, justice, and joy.

If there be an infinite Being, he does not need our help - we need not waste our energies in his defense.

In a world of cruelty, sympathy is a crime, and in a world of lies, truth is blasphemy.

The falling leaf that tells of autumn's death is, in a subtler sense, a prophecy of spring.