Dyson was a hero of mine because I couldn't understand Feynman because I didn't understand the go of it. I mean, I knew about the pictures. I knew there were these pictures and I didn't know why it worked. It just drove me crazy. I just... I couldn't use it because I didn't have to use it and I just… and Schwinger I could understand, but Schwinger's calculus was so complicated. Oppenheimer once said of Schwinger when Schwinger does a calculation… he said, 'When most people do a calculation, they want to show how a problem is to be done. When Schwinger does a calculation, he wants to show that only he can do the problem'. And then there came Dyson and Dyson was like a revelation. You could understand what Schwinger did, you could understand Feynman, it was marvellous. Marvellous. I loved those papers. That Dyson did not get a Nobel Prize for this, I think is just… is an obscenity. I mean, the list of people… you know, Bockhoff didn't get a Nobel prize either but… crazy. So Dyson came to Harvard to give a series of lectures and they were all marvellous. Dyson is a wonderful lecturer, absolutely wonderful. And then my thesis advisor, Klein, wanted to talk to him about something and Dyson… we went to the office which Dyson had temporarily and Dyson was on a couch in the office. I think he was pretending to be asleep. And Klein kept talking without noticing the fact that Dyson was either… was paying no attention. He was sort of asleep. I mean, Dyson didn't want to hear. I thought that was interesting.