If we had a reliable way to label our toys good and bad, it would be easy to regulate technology wisely. But we can rarely see far enough ahead to know which road leads to damnation. Whoever concerns himself with big technology, either to push it forward or to stop it, is gambling in human lives.

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.

When World War II came along, which was when I was a teenager, we all expected we would have anthrax bombs and this kind of stuff. We thought it would be a biological war. Fortunately it wasn't and, but it's because the danger is still there and by some miracle we escaped all that, so you never can tell what it going to happen, but biology certainly could be even worse than physics and chemistry.

For any speculation which does not at first glance look crazy, there is no hope.

We must be careful not to discourage our twelve-year-olds by making them waste the best years of their lives preparing for examinations.

The brain, being analog, is able to grasp images so much better. The brain is just designed for comparing images and some patterns - patterns in space and patterns in time - which we do amazingly well. Computers can do it, too, but not in anything like the same kind of flexibility.

Of course, the English countryside is completely artificial. It was naturally a forest; they chopped down the trees and made it into what it is now: really a beautiful country.