Genius: The Life and Science of Richard Feynman

by James Gleick

Nature uses only the longest threads to weave her pattern, so each small piece of the fabric reveals the organization of the entire tapestry.

(In Mexico he had grown interested in the deciphering of the great ancient codices, hieroglyphic manuscripts that employed long tables of bars and dots to set down an intricate knowledge of the movements of sun, moon, and planets. Codes, mathematics, and astronomy—eventually he delivered a lecture at Caltech on deciphering Mayan hieroglyphics.

For Feynman, especially, the tension between alternative theories served as a creative force, an engine for generating new knowledge. Perhaps more than any living physicist, he had made a specialty of learning what models could be derived from which principles, and what models from each other. To Dyson’s astonishment, he had stood at a blackboard one day in 1948 and interrupted their heady discussions of quantum electrodynamics to show him something different. Sketching quickly, he derived the nineteenth-century Maxwell field equations—the classical understanding of electricity and magnetism—backward from the new quantum mechanics.

He understood explanations as a surgeon understands knives. He had a set of practical tests, heuristics, that he applied when reaching a judgment about a new idea in physics: for example, did it explain something unrelated to the original problem. He would challenge a young theorist: What can you explain that you didn’t set out to explain? He knew that why? is a question without an end and that our knowledge of things is inextricable from the language we use. The words and analogies from which we build our explanations are culpably linked with the things explained. Explanans and explanandum are inextricable after all.

He believed in the primacy of doubt, not as a blemish upon our ability to know but as the essence of knowing. The alternative to uncertainty is authority, against which science had fought for centuries. “Great value of a satisfactory philosophy of ignorance,” he jotted on a sheet of notepaper one day. “... teach how doubt is not to be feared but welcomed.”

he saw a danger in tying moral guidance to unpalatable myths, as religion did, and he resented the common view that science, with its merciless unraveling and explaining, was an enemy of the emotional appreciation of beauty. “Poets say science takes away from the beauty of the stars—mere globs of gas atoms,” he wrote in a famous footnote. I too can see the stars on a desert night, and feel them. But do I see less or more? The vastness of the heavens stretches my imagination—stuck on this carousel my little eye can catch one-million-year-old light. A vast pattern—of which I am a part.... What is the pattern, or the meaning, or the why? It does not do harm to the mystery to know a little about it.

He believed, too, in an independence of moral belief from any particular theory of the machinery of the universe. An ethical system that depended on faith in a watchful or vengeful God was unnecessarily fragile, prone to collapse when doubt began to undermine faith.

He believed that it was not certainty but freedom from certainty that empowered people to make judgments about right and wrong: knowing that they could never be more than provisionally right, but able to act nonetheless.

He pointed out a remarkable irony of the story. So many of the ideas he nursed on his way to his Nobel Prize–winning work had themselves proved faulty: his first notion that a charge should not act on itself; the whole Wheeler-Feynman half-advanced, half-retarded electrodynamics. Even his path integrals and his view of electrons moving backward in time were only aids to guessing, not essential parts of the theory, he said. The method used here, of reasoning in physical terms, therefore, appears to be extremely inefficient. On looking back over the work, I can only feel a kind of regret for the enormous amount of physical reasoning and mathematical re-expression....

But he also believed that the inefficiency, the guessing of equations, the juggling of alternative physical viewpoints were, even now, the key to discovering new laws.

He concluded with advice to students: The chance is high that the truth lies in the fashionable direction. But, on the off-chance that it: is in another direction—a direction obvious from an unfashionable view of field theory—who will find it? Only someone who has sacrificed himself by teaching himself quantum electrodynamics from a ...

So it’s necessary to increase the amount of variety ... and the only way to do it is to implore you few guys to take a risk with your lives that you will never be heard of again, and go off in the wild blue yonder and see if you can figure it out.”

He turned down honorary degrees offered by the University of Chicago and by Columbia University and thus finally kept the promise he had made to himself on the day he received his doctorate from Princeton. He turned down hundreds of other propositions with a curtness that impressed even his protective secretary. To a book publisher who had invited him to “introduce a draft of fresh air into a rather stuffy area,” he wrote: “No sir. The area is stuffy from too much hot air already.” He refused to sign petitions and newspaper advertisements; the Vietnam War was now drawing the opposition of many scientists, but he would not join them publicly. Feynman, Nobel laureate, found that even canceling a magazine subscription took an entire correspondence. “Dear Professor Feynman,” began a long letter from the editor of Physics Today, the magazine whose second issue had carried his article about the Pocono conference in 1948: The comment you sent back with our questionnaire on our May issue (“I never read your magazine. I don’t know why it is published. Please take me off your mailing list. I don’t want it.”) poses some interesting questions for us.... Four hundred words later, the editor had not given up: I apologize for asking any more of your time, but all of us at Physics Today will appreciate it very much if we can have amplification of your earlier comments.

He almost never participated in the business of his department at Caltech: tenure decisions, grant proposals, or any of the other administrative chores that constitute overhead on most scientists’ time. Caltech’s divisions, like the science departments at every American university, were largely financed through a highly structured process of applications to the Department of Energy, the Department of Defense, and other government agencies. There were group applications and individual applications, supporting salaries, students, equipment, and overhead. At Caltech a senior professor who could arrange to have the air force, for example, pay a portion of his salary was rewarded with a discretionary kitty with which he could travel, buy a computer, or support a graduate student.

He protected his freedom as though it were a dying candle in a hard wind. He was willing to risk hurting his friends. Hans Bethe turned sixty the year after Feynman won his Nobel Prize, and Feynman refused to send a contribution to the customary volume of articles in his honor.

In 1983, looking back on the evolution of particle physics since the now-historic Shelter Island conference, Murray Gell-Mann said, uncontroversially, that he and his colleagues had developed a theory that “works.”

Feynman revels in them. He believes that a certain amount of imprecision and ambiguity is essential to communication.

As he could instantly see, Feynman’s essential insight was to place himself once again in the electron, to see what the electron would see at light speed.

Zweig’s aces, Gell-Mann’s quarks, and Feynman’s partons became three paths to the same destination. These constituents of matter served as the quanta of a new field, finally making possible a field theory of the strong force.

I’m tired of thinking of the same thing. I need to think of something else. Because I got stuck—see, if it would keep going it would be all right, but it’s hard to get any new results.... This parton thing has been so successful that I have become fashionable. I have to find an unfashionable thing to do.

Feynman promised to prepare a freshman lecture on it. For once, he failed. “I couldn’t reduce it to the freshman level,” he said a few days later, and added, “That means we really don’t understand it.”

Feynman could not make his real point without drifting into philosophy. It was crucial, he argued, to distinguish clear language from precise language. The textbooks placed a new emphasis on precise language: distinguishing “number” from “numeral,” for example, and separating the symbol from the real object in the modern critical fashion—pilpul for schoolchildren, it seemed to Feynman. He objected to a book that tried to teach a distinction between a ball and a picture of a ball

An MIT historian, Charles Weiner, persuaded him to cooperate in what became the most thorough and serious of his interviews. For a while Feynman considered collaborating with Weiner on a biography. They sat in Feynman’s screened back patio while Carl played in a tree house nearby.

He began dating his scientific notes as he worked, something he had never done before. Weiner once remarked casually that his new parton notes represented “a record of the day-to-day work,” and Feynman reacted sharply. “I actually did the work on the paper,” he said. “Well,” Weiner said, “the work was done in your head, but the record of it is still here.” “No, it’s not a record, not really. It’s working. You have to work on paper, and this is the paper. Okay?” It was true that he wrote in astonishing volume as he worked—long trains of thought, almost suitable to serve immediately as lecture notes.

They knew they had a remarkable central figure, a scientist who prided himself not on his achievements in science—these remained deep in the background—but on his ability to see through fraud and pretense and to master everyday life. He underscored these qualities with an exaggerated humility; he took the tone of a boy calling the grownups Mr. and Mrs. and asking politely dangerous questions.

Whether or not nature has an ultimate, simple, unified, beautiful form is an open question, and I don’t want to say either way.

String theory relies on Feynman’s sum-over-histories method as an essential underlying principle; the theory views particle events as topological surfaces and computes probability amplitudes by summing over all possible surfaces. Feynman kept his distance, sometimes saying that perhaps he was too old to appreciate the new fashion. String theory seemed too far from experiment. He suspected that the string theorists were not trying hard enough to prove themselves wrong. In the meantime he never adopted the rhetoric of GUT’s. It made him uncomfortable. He retreated into the stance that he himself merely solved problems as they came along.

When his son, Carl, ended his flirtation with philosophy and took up computer science, Feynman, too, looked again at the field he had helped pioneer at Los Alamos. He joined two Caltech authorities on computation, John Hopfield and Carver Mead, in constructing a course on issues from brain analogues and pattern recognition to error correction and uncomputability. For several summers he worked with the founders of Thinking Machines Corporation, near MIT, creating a radical approach to parallel processing; he served as a high-class technician, applying differential equations to the circuit diagrams, and as an occasional wise man among the young entrepreneurs (“Forget all that ‘local minima’ stuff—just say there’s a bubble caught in the crystal and you have to shake it out”). And he began to produce maverick research at the intersection of computing and physics: on how small computers could be; on entropy and the uncertainty principle in computing; on simulating quantum physics and probabilistic behavior; and on the possibility of building a quantum-mechanical computer, with packets of spin waves roaming ballistically back and forth through the logic gates.

In one corner of his dusty office blackboard he had written a pair of self-conscious mottoes: “What I cannot create I do not understand” and “Know how to solve every problem that has been solved.”

You see, one thing is, I can live with doubt and uncertainty and not knowing. I think it’s much more interesting to live not knowing than to have answers which might be wrong. I have approximate answers and possible beliefs and different degrees of certainty about different things, but I’m not absolutely sure of anything and there are many things I don’t know anything about, such as whether it means anything to ask why we’re here.... I don’t have to know an answer. I don’t feel frightened by not knowing things, by being lost in a mysterious universe without any purpose, which is the way it really is as far as I can tell. It doesn’t frighten me.