The PhD system is the real root of the evil of academic snobbery. People who have PhDs consider themselves a priesthood, and inventors generally don't have PhDs.

I think that the artificial-intelligence people are making a lot of noise recently, claiming that artificial intelligence is making huge progress and we're going to be outstripped by the machines.

It's us that's really amazing.

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 not going to be just humans colonizing space, it's going to be life moving out from the Earth, moving it into its kingdom. And the kingdom of life, of course, is going to be the universe.

All the time worrying about pushing the children and getting them to be mathematically literate and all that stuff. It's terribly hard on the kids. It's also hard on the teachers. And I think it's totally useless.

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.