Dyson’s letters are particularly engaging when they describe the occasional flashes of illumination that lead to a scientific insight. Riding on a cross-continental Greyhound bus, past Iowa cornfields, Dyson notes: “On the third day of the journey a remarkable thing happened; going into a sort of semi-stupor as one does after 48 hours of bus riding, I began to think very hard about physics, and particularly about the rival radiation theories of Schwinger and Feynman. Gradually my thoughts grew more coherent, and before I knew where I was, I had solved the problem that had been in the back of my mind all this year, which was to prove the equivalence of the two theories. … This piece of work is neither difficult nor particularly clever, but it is undeniably important.” Dyson was chiefly pleased that once back in Princeton, he would “now encounter Oppenheimer with something to say which will interest him.”
Dyson is fascinated by Oppenheimer: “I have been observing rather carefully his behavior during seminars. If one is saying, for the benefit of the rest of the audience, things that he knows already, he cannot resist hurrying one on to something else; then when one says things that he doesn’t know or immediately agree with, he breaks in before the point is fully explained with acute and sometimes devastating criticisms, to which it is impossible to reply adequately even when he is wrong.” Dyson thought this “impatience” demonstrated by “Oppy” was beyond his control, and in any case, “To me, the interruptions provided many valuable new ideas.”
The letters are also sometimes painfully candid and close to home. In early 1957, Dyson writes his parents from Aspen, Colo., where he has gone on vacation with his mathematician wife, Verena — and he has to report that Verena has “fallen in love and decided to run away” with one of Freeman’s old Cambridge friends. Dyson is clearly devastated that his wife of six years is walking out of what he had considered a “happy” marriage, leaving behind two young children, Esther and George. (Both children forged innovative careers, Esther as a digital-age journalist and angel investor, and George as a historian of science.) Freeman stoically writes his parents: “Please do not offer me your sympathy or your pity. I have been happy in this marriage, and I have no regrets now it is over. … What she has done may be crazy, but it is not irresponsible.”
And then within months, Dyson’s letters begin to mention the name of Imme Jung, the Berlin-born, 20-year-old au pair Verena had hired just before she walked out. “The more I see of Imme,” Dyson writes his parents, “the more impressed I am with her firm and solid character.” Escorting her to dinner at the Oppenheimers one night that spring, Dyson feels like “Higgins taking his Eliza to the ball; after all, Imme is extremely young and has little formal education.” But fortunately, that night Oppenheimer himself was charming: “Oppy especially went out of his way to be friendly to her.”
Dyson was falling in love with his soon-to-be second wife. In an italicized note, he explained that for the next two years as a single dad, while the divorce was taking shape, “I held back from any display of affection for Imme, but it was obvious to all.”
So, these letters are not only about science and politics. There is a love story too! They went on to have four more daughters; Imme became a master runner — the Dysons like to joke that “he has the brains, she has the legs.” If this “autobiography through letters” is not quite memoir, maybe it will nevertheless inspire a film.