There is no significant example in history, before our time, of a society successfully maintaining moral life without the aid of religion.

Nature has never read the Declaration of Independence. It continues to make us unequal.

Every science begins as philosophy and ends as art; it arises in hypothesis and flows into achievement.

A cat has a reputation to protect. If it had a halo, it would be worn cocked to one side.

A history of civilization shares the presumptuousness of every philosophical enterprise: it offers the ridiculous spectacle of a fragment expounding the whole. Like philosophy, such a venture has no rational excuse, and is at best but a brave stupidity; but let us hope that, like philosophy, it will always lure some rash spirits into its fatal depths.

To rulers religion, like almost everything else, is a tool of power.

Woe to him who teaches men faster than they can learn.