Will we rise to the challenge and prove our capacity for genuine altruism by ending our ruthless exploitation of the species in our power, not because we are forced to do so by rebels or terrorists, but because we recognize that our position is morally indefensible?

Should one break in and free the animals? That is illegal, but the obligation to obey the law is not absolute. It was justifiably broken by those who helped runaway slaves in the American South, to mention only one possible parallel.

Charitable giving is a huge sector in the United States. It amounts to $350 billion a year. And yet, I can't help feeling that a lot of that is wasted because people have not been thinking about how to do it as effectively as possible.

If we can put a man on the moon and sequence the human genome, we should be able to devise something close to a universal digital public library.

I don't think there's much point in bemoaning the state of the world unless there's some way you can think of to improve it. Otherwise, don't bother writing a book; go and find a tropical island and lie in the sun.

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.

The idea that we can actually have an impact on places more or less instantly, too, by responding in some way or not responding, I think, also makes it true.