If a man would follow, today, the teachings of the Old Testament, he would be a criminal. If he would follow strictly the teachings of the New, he would be insane.

If abuses are destroyed, man must destroy them. If slaves are freed, man must free them. If new truths are discovered, man must discover them. If the naked are clothed; if the hungry are fed; if justice is done; if labor is rewarded; if superstition is driven from the mind; if the defenseless are protected, and if the right finally triumphs, all must be the work of man. The grand victories of the future must be won by man, and by man alone.

I am simply in favor of intellectual hospitality-that is all. You come to me with a new idea. I invite you into the house. Let us see what you have. Let us talk it over. If I do not like your thought, I will bid it a polite "good day." If I do like it, I will say: "Sit down; stay with me, and become a part of the intellectual wealth of my world."

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.

Theology is not what we know about God, but what we do not know about Nature.

Most people can bear adversity. But if you wish to know what a man really is, give him power.

Twenty years after the death of Luther there were more Catholics than when he was born. And twenty years after the death of Voltaire there were millions less than when he was born.