To make a discovery is not necessarily the same as to understand a discovery.

One of the things I learned, one of the strangest things, is how to think. There was nothing else to do. I couldn't see people, or go for a walk in the forest. All I had was my head and my books, and I thought a lot.

I knew all the time I was going to get through the war. It was completely irrational, a silly idea, but I was not going to lie down and get myself killed. I was going to get out of it.

To make a discovery is not necessarily the same as to understand a discovery.

The rule of the game was never assume that anybody, however honorable, would be able to stand up under torture. If Mr. X, who knew where I was, was caught for some reason, I should move.

A number of current theoretical explorations will turn out to be passing fancies...

Deliberately or not, every author is of course present in every book he or she writes - even in a scientific text.