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.

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.

In mathematics we find the primitive source of rationality; and to mathematics must the biologists resort for means to carry out their researches.

Ideas govern the world, or throw it into chaos.

Woman is the most moral element in all humanity.

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

The only real life is the collective life of the race; individual life has no existence except as an abstraction.