A model is such a fascinating toy that you fall in love with your creation.

Of course, long-distance running has to do with the fact that we're hunters.

For a physicist mathematics is not just a tool by means of which phenomena can be calculated, it is the main source of concepts and principles by means of which new theories can be created.

The purpose of thinking about the future is not to predict it but to raise people's hopes.

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 is no way to find the best design except to try out as many designs as possible and discard the failures.

The whole point of science is that most of it is uncertain. That's why science is exciting--because we don't know. Science is all about things we don't understand. The public, of course, imagines science is just a set of facts. But it's not. Science is a process of exploring, which is always partial. We explore, and we find out things that we understand. We find out things we thought we understood were wrong. That's how it makes progress.