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

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

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.

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?

There is not a soul on Earth who can read the deluge of physics publications in its entirety. As a result, it is sad but true that physics has irretrievably fallen apart from a cohesive to a fragmented discipline. ... It was not that long ago that people were complaining about two cultures. If we only had it that good. today.

[Heisenberg's seminal 1925 paper initiating quantum mechanics marked] one of the great jumps—perhaps the greatest—in the development of twentieth century physics.

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.