Fear is religion, courage is science.

To avoid pain we must know the conditions of health. For the accomplishment of this end we must rely upon investigation instead of faith, upon labor in place of prayer. Most misery is produced by ignorance. Passions sow the seeds of pain.

Is there an intelligent man or woman now in the world who believes in the Garden of Eden story? If you find any man who believes it, strike his forehead and you will hear an echo. Something is for rent.

Whoever imagines himself a favorite with God holds others in contempt.

Mental slavery is mental death, and every man who has given up his intellectual freedom is the living coffin of his dead soul.

Strange but true: those who have loved God most have loved men least.

There will never be a generation of great men until there has been a generation of free women - of free mothers.