Know yourself to improve yourself.

The dead govern the living.

The sacred formula of positivism: love as a principle, the order as a foundation, and progress as a goal.

Every attempt to employ mathematical methods in the study of chemical questions must be considered profoundly irrational and contrary to the spirit of chemistry.... if mathematical analysis should ever hold a prominent place in chemistry -- an aberration which is happily almost impossible -- it would occasion a rapid and widespread degeneration of that science.

Woman is the most moral element in all humanity.

The word right should be excluded from political language, as the word cause from the language of philosophy.

Know yourself to improve yourself.