The commonest objection to birth control is that it is against nature.

Nothing of importance is ever achieved without discipline. I feel myself sometimes not wholly in sympathy with some modern educational theorists, because I think that they underestimate the part that discipline plays. But the discipline you have in your life should be one determined by your own desires and your own needs, not put upon you by society or authority.

What science cannot discover, mankind cannot know.

Science is what we know, and philosophy is what we don't know.

There was, I think, never any reason to believe in any innate superiority of the male, except his superior muscle.

With civilized men..., it is, I think, chiefly love of excitement which makes the populace applaud when war breaks out; the emotion is exactly the same as at a football match, although the results are sometimes somewhat more serious.

It is in our hearts that evil lies, and it is from our hearts that it must be plucked out.