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

Once I even took the train to Utrecht, forty miles from Amsterdam, with my yellow star, this star which I still have. Why did I go? I just wanted to visit some friends. I was a little bit crazy, a little bit insane.

Of course, relative citation frequencies are no measure of relative importance. Who has not aspired to write a paper so fundamental that very soon it is known to everyone and cited by no one?

Some years ago John Kenneth Galbraith wrote in an essay on his efforts at writing a history of economics: 'As one approaches the present, one is filled with a sense of hopelessness; in a year and possibly even a month, there is now more economic comment in the supposedly serious literature than survives from the whole of the thousand years commonly denominated as the Middle Ages ... anyone who claims to be familiar with it all is a confessing liar.' I believe that all physicists would subscribe to the same sentiments regarding their own professional literature. I do at any rate.

One of the absolute rules I learned in the war was, don't know anything you don't need to know, because if you ever get caught they will get it out of you.

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...