If only people would realize that moral principles are like measles.... They have to be caught. And only the people who've got them can pass on the contagion.

A man may have strong humanitarian and democratic principles, but if he happens to have been brought up as a bath-taking, shirt-changing lover of fresh air, he will have to overcome certain physical repugnance before he can bring himself to put those principles into practice.

The vast majority of human beings are not interested in reason or satisfied with what it teaches.

I know quite well that one needs ridiculous, mad situations like that; one can't write really well about anything else. Why was that old fellow such a marvelous propaganda technician? Because he had so many insane, excruciating things to get excited about. You've got to be hurt and upset; otherwise you can't think of the really good, penetrating, X-rayish phrases.

Orthodoxy is the diehard of the world of thought. It learns not, neither can it forget.

In any race between human numbers and natural resources, time is against us.

Medical science is making such remarkable progress that soon none of us will be well.