If a man, holding a belief which he was taught in childhood or persuaded of afterwards, keeps down and pushes away any doubts which arise about it in his mind, purposely avoids the reading of books and the company of men that call in question or discuss it, and regards as impious those questions which cannot easily be asked without disturbing it - the life of that man is one long sin against mankind.

An atom must be at least as complex as a grand piano.

We may always depend on it that algebra, which cannot be translated into good English and sound common sense, is bad algebra.

He who truly believes that which prompts him to an action has looked upon the action to lust after it, he has committed it already in his heart.

Our lives our guided by that general conception of the course of things which has been created by society for social purposes.

Thought is powerless, except it make something outside of itself: the thought which conquers the world is not contemplative but active.

There is one thing in the world more wicked than the desire to command, and that is the will to obey.