I don't believe I can really do without teaching. The reason is, I have to have something so that when I don't have any ideas and I'm not getting anywhere, I can say to myself, "At least I'm living; at least I'm doing something. I'm making some contribution." It's just psychological.

The game I play is a very interesting one. It's imagination in a straightjacket, which is this: that it has to agree with the known laws of physics. ... It requires imagination to think of what's possible, and then it requires an analysis back, checking to see whether it fits, whether its allowed, according to what's known, okay?

God was invented to explain mystery. God is always invented to explain those things that you do not understand.

We absolutely must leave room for doubt or there is no progress and no learning. There is no learning without having to pose a question. And a question requires doubt. People search for certainty. But there is no certainty.

One of the ways of stopping science would be only to do experiments in the region where you know the law. But experimenters search most diligently, and with the greatest effort, in exactly those places where it seems most likely that we can prove our theories wrong. In other words, we are trying to prove ourselves wrong as quickly as possible, because only in that way can we find progress.

If an apple was magnified to the size of the Earth, then the atoms in the apple would be approximately the size of the original apple.

The work I have done has, already, been adequately rewarded and recognized. Imagination reaches out repeatedly trying to achieve some higher level of understanding, until suddenly I find myself momentarily alone before one new corner of nature's pattern of beauty and true majesty revealed. That was my reward.