If you go to London now, not everything is beautiful, but it's amazingly better than it was. And the Thames is certainly a lot better: There are fish in the Thames.

The great advances in science usually result from new tools rather than from new doctrines.

I belonged to a small minority of boys who were lacking in physical strength and athletic prowess. ... We found our refuge in science. ... We learned that science is a revenge of victims against oppressors, that science is a territory of freedom and friendship in the midst of tyranny and hatred.

I'm happy that I've raised six kids, and not one of them is a Ph.D.

We cannot hope to either understand or to manage the carbon in the atmosphere unless we understand and manage the trees and the soil too.

If you don't have a nasty obituary you probably didn't matter.

The thing that makes me most optimistic is China and India - both of them doing well.