Irrationally held truths may be more harmful than reasoned errors

But orthodoxy is the Bourbon of the world of thought.

A man has no reason to be ashamed of having an ape for his grandfather.

To a person uninstructed in natural history, his country or sea-side stroll is a walk through a gallery filled with wonderful works of art, nine-tenths of which have their faces turned to the wall.

Extinguished theologians lie about the cradle of every science as the strangled snakes beside that of Hercules

I cannot but think that he who finds a certain proportion of pain and evil inseparably woven up in the life of the very worms, will bear his own share with more courage and submission

Life is too short to occupy oneself with the slaying of the slain more than once.