Individual versus group selection results in a mix of altruism and selfishness, of virtue and sin, among the members of a society. If one colony member devotes its life to service over marriage, the individual is of benefit to the society, even though it does not have personal offspring. A soldier going into battle will benefit his country, but he runs a higher risk of death than one who does not. An altruist benefits the group, but a layabout or coward who saves his own energy and reduces his bodily risk passes the resulting social cost to others.

What's been gratifying is to live long enough to see molecular biology and evolutionary biology growing toward each other and uniting in research efforts.

The great challenge of the twenty-first century is to raise people everywhere to a decent standard of living while preserving as much of the rest of life as possible.

Every kid has a bug period, I like to say, and I just got so fascinated and I had that experience, that wonderful life of being able to go out on my own without really any supervision at all. I just lucked out that way. I was trusted as a kid.

One thing I did was grow up as an ardent naturalist. I never grew out of my bug period.

The living environment is the biosphere, the thin layer around the world of living organisms. We're part of that. Our existence is dependent on it in ways that people haven't even begun to appreciate. Our existence depends not just on its existence, but its stability and its richness.

Human nature is deeper and broader than the artificial contrivance of any existing culture.