To understand a science, it is necessary to know its history.

All good intellects have repeated, since Bacon’s time, that there can be no real knowledge but which is based on observed facts.

Demography is destiny.

Nothing is destroyed until it is replaced.

Positivism is a theory of knowledge according to which the only kind of sound knowledge available to human kind is that if science grounded in observation.

Know yourself to improve yourself.

Religion is an illusion of childhood, outgrown under proper education.

To reorganize society without God or King, by the systematic culture of Humanity.

The law is this: that each of our leading conceptions-each branch of our knowledge-passes successively through three different theoretical conditions: the Theological, or fictitious: the Metaphysical, or abstract; and the Scientific, or positive.

Woman is the most moral element in all humanity.