I like people who are working on practical things and who are working in teams. It's not so important to get the glory. It's much more important to get something that works. It's a better way to live.

It's amazing how much progress there's been in China, and also India. Those are the places that really matter - they're half of the world's population. They're the places where things are enormously better now than they were 50 years ago. And I don't see anything that's going to stop that.

A model is done when nothing else can be taken out.

One factor that has remained constant through all the twists and turns of the history of physical science is the decisive importance of the mathematical imagination.

It makes very little sense to believe the output of the climate models.

Mostly I'm just writing books for the public, and so I try to describe for the public what the choices are, what they might have to expect in the future and so by warning people ahead of time maybe you have an effect.

There are three reasons, . . . apart from scientific considerations, mankind needs to travel in space. The first . . . is garbage disposal; we need to transfer industrial processes into space so that the earth may remain a green and pleasant place for our grandchildren to live in. The second . . . to escape material impoverishment: the resources of this planet are finite, and we shall not forego forever the abundance of solar energy and minerals and living space that are spread out all around us. The third . . . our spiritual need for an open frontier.