We wait until Pandora's box is opened before we say, "Wow, maybe we should understand what's in that box." This is the story of humans on every problem.

To turn the other cheek is to teach would-be cheats that cheating pays.

I don't think nationalism is alone holding the field; it's in contention with a lot of different things.

If penicillin had been judged by its toxicity to guinea pigs, it might never have been used by man.

I would not question the sincerity of vegetarians who take little interest in Animal Liberation because they give priority to other causes; but when nonvegetarians say that "human problems come first" I cannot help wondering what exactly it is that they are doing for human beings that compels them to continue to support the wasteful, ruthless exploitation of farm animals.

All the particular moral judgments we intuitively make are likely to derive from discarded religious systems, from warped views of sex and bodily functions, or from customs necessary for the survival of the group in social and economic circumstances that now lie in the distant past.

I'd much rather be part of a society which greatly honors and respects people who are altruists and who are effective in their altruism, than one that either admires people because they're, you know, celebrity movie stars or because they're super wealthy just no matter what they do with their wealth because I think we ought to try to encourage more people to act in that way.