The trouble with always trying to preserve the health of the body is that it is so difficult to do without destroying the health of the mind.

I despise Birth-Control first because it is ... an entirely meaningless word; and is used so as to curry favour even with those who would first recoil from its real meaning. The proceeding these quack doctors recommend does not control any birth. ...

Science is the study of the admitted laws of existence, which cannot prove a universal negative about whether those laws could ever be suspended by something admittedly above them. It is as if we were to say that a lawyer was so deeply learned in the American Constitution that he knew there could never be a revolution in America..

The thing that cannot be defined is the first thing; the primary fact.

The perplexity of life arises from there being too many interesting things in it for us to be interested properly in any of them.

Science in the modern world has many uses; its chief use, however, is to provide long words to cover the errors of the rich.