Men are not allowed to think freely about chemistry and biology: why should they be allowed to think freely about political philosophy?

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

Ideas govern the world, or throw it into chaos.

Every science consists in the coordination of facts; if the different observations were entirely isolated, there would be no science.

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

Each department of knowledge passes through three stages. The theoretic stage; the theological stage and the metaphysical or abstract stage.