Feynman at 100


In his years at Caltech, Richard Feynman—theoretical physicist, Nobel laureate, famed lecturer, bongo player—made an outsized impression on all who came into contact with him. Here, a hundred years after his birth, is a selection of reflections on the multifaceted scientific genius from his Institute colleagues and friends, many drawn from the Caltech Archives Oral History Project. 

Feynman the teacher

We were organizing an AAAS [American Association for the Advancement of Science] meeting here in Southern California, and the planning committee said, “We want to get some speaker who can talk to eight- and nine-year-olds. We’re going to bus in 3,000 of them from around L.A. to the California Science Center downtown by USC.” …. So, I said, “Well, Dick’s the guy. I’ll ask Dick.” And I said, “Dick, will you do this?” And he said, “Sure I will.” He showed up in his informal outfit, and I remember that 3,000 kids sat outside on this big grassy knoll around the science center. ... He talked for about 40 minutes, and they were fascinated. They didn’t move. They were all looking at him. Gee, whiz. He had a way. He had a way with all ages of people. Here are nine-year-olds, and you figure—in three minutes, they’re going to be running around, getting into trouble, doing all kinds of stuff. They didn’t move. … Just loved the guy. I couldn’t believe it. He did such a job. But that was Dick Feynman. 

—Harry Gray, Arnold O. Beckman Professor of Chemistry, recalling an impromptu talk by Feynman outside the California Science Center



Why did Feynman accept the assignment to devote all of his formidable energy for two years to teaching beginning physics as it had never been taught before? My guess is that there were three basic reasons. One was that … he loved to have an audience, and this gave him a bigger one than he usually had in the graduate courses he normally taught. The second was that he genuinely cared about students. He simply thought that teaching freshmen was an important thing to do, and so he couldn't turn down the invitation when it came. The third reason—and this might have been the most important of all—was the sheer challenge of reformulating physics, as he understood it, so that it could be presented to young students. This was a specialty of his. In fact, it was the standard by which he measured whether something was really understood. Once I asked him to explain to me, so that I could understand it, why spin-V2 particles obey Fermi-Dirac statistics. Gauging his audience perfectly, he said, "I'll prepare a freshman lecture on it." But a few days later he came to me and said: "You know, I couldn't do it. I couldn't reduce it to the freshman level. That means we really don't understand it."

—David Goodstein, Frank J. Gilloon Distinguished Teaching and Service Professor, Emeritus; Professor of Physics and Applied Physics, Emeritus, from an article in Physics Today, February 1989


[Feynman] started writing some equations on the board, and then he said, "I understand that Professor Oppenheimer has just been here and has given a series of lectures on the same subject. And therefore, I won't define the symbols—either." [Laughter] It was a funny kind of thing; it tells you something about the person, to realize that when Oppy would come and lecture, the place would be jammed to the rafters at the first lecture and then about three-quarters full the second lecture, and then one-quarter full. And at the final lecture there'd be only a couple of rows filled—that was the department; they would stick it out through to the end. But when Feynman came, it was the reverse. That is, people didn't know him very well, and for the first lecture, the hall was a quarter full; then at the next lecture it was three-quarters full; and at the last lecture it was overflowing—right to the ceiling. [Laughter] Feynman was really great to have around. 

Robert Leighton (1919-1977), William L. Valentine Professor of Physics, Emeritus

I had Dick Feynman for mathematical physics. I used to go around to all his seminars when I was an undergrad, even. I couldn’t understand any of the mathematics at all, but every once in a while, he’d stop and he’d say, “What this really means is...,” and I could understand that. 

—Carver Mead, Gordon & Betty Moore Professor of Engineering & Applied Science, Emeritus


When teaching the sophomore Waves course, sometimes I refer to Feynman’s lecture notes, to see how he explained particular ideas. That usually turns into a fun yet distracting reading experience. It is fascinating to read about ratchet and pawl as a (failed) attempt to violate laws of thermodynamics. It is also amazing to see how special relativity was introduced right after Newtonian mechanics, quantum mechanics was brought up before electromagnetism, and how the whole book begins with a grand effort to set up the stage for physics, by introducing notions like energy, time, space, and probability and talking about the relation of physics to other sciences. Many times I failed to find the particular calculation or explanation I was looking for, but instead came away with inspirations about how to  teach physics in a more vivid way and with a broader perspective.

—Xie Chen, Associate Professor of Theoretical Physics


Feynman the thinker

You know how Richard Feynman was once recruited by the University of Chicago, which offered to double his salary or something like that. He was asked, “Why wouldn’t you leave Caltech and take this offer?” and I think—to paraphrase—he said, “At Caltech, if I moved a meter or two, I would be in collision with somebody who will excite my interest.”

—Ahmed Zewail (1946-2016), Linus Pauling Professor of Chemistry and Professor of Physics; Nobel Laureate

One day I’m sitting in my lab and the phone rings: “Hello, Galston? This is Feynman.” … He said, “Do you have a few minutes? I’d like to come over.” And I said, “Come on.” He came in carrying my book. He said, “I read your book [Principles of Plant Physiology] last night.” [Laughter] Now, this is a 500-page book in a field that he has no knowledge of, presumably. And he says, “I want to discuss a few items with you.” [Laughter] He then proceeds—he really knew what he had read—and he said, “Why don’t you guys do such-and-so experiment?” I said, “That’s not feasible.” And he said, “Sure it is! With the aid of a physicist you can do it.” And he suggested various practical things, most of which have since been done, and he was absolutely right. But here he was, having picked up my book and rambled through it in one night, criticizing someone who’s in the field. Well, I was overwhelmed by this. 

—Arthur W. Galston (1920-2008), Associate Professor of Biology


Feynman played a very key role [in understanding the collapse of supermassive stellar objects].

He bumped into me one day, and he says, “Willy, you know those supermassive objects that you and Fred have been working on are unstable. They’ll collapse, due to general relativity.” And I was just shocked, because Fred and I, in our first papers, had made a completely Newtonian solution of the problem—just standard stellar structure, although Fred had written a few kind of cryptic remarks about the possibility of instability. But I hadn’t understood really what Fred was talking about, and we hadn’t emphasized it. But it was Dick Feynman who pointed out that if you put in general relativity, then a supermassive object was unstable. The general relativistic terms reduce the effective gamma of the equation of state below the value for which a star can be stable. So, he actually then gave a lecture in one of his classes and Icko Iben, who was a postdoc with me at the time, was attending Dick’s classes. So, Icko Iben immediately began making numerical solutions of the problems, using the Caltech computer, and convinced me that Dick was right. I immediately began to put general relativity in, but only in terms of the next approximation after Newton, and found right away that Dick was right, that the damn things would collapse. 

—William A. Fowler (1911-1995), Professor of Physics; Nobel Laureate


Feynman the multitasker

It is remarkable that concurrently with this course on gravitation, Feynman was also creating and teaching an innovative course in sophomore (second-year undergraduate) physics, a course that would become immortalized as the second and third volumes of The Feynman Lectures on Physics. Each Monday, Feynman would give his sophomore lecture in the morning and the lecture on gravitation after lunch. Later in the week would follow a second sophomore

lecture and a lecture for scientists at Hughes Research Laboratories in Malibu. Besides this teaching load and his own research, Feynman was also serving on a panel to review textbooks for the California State Board of Education, itself a consuming task, as is vividly recounted in Surely You're Joking, Mr. Feynman. Steven Frautschi, who attended the lectures on gravitation as a young Caltech assistant professor, remembers Feynman later saying that he was "utterly exhausted" by the end of the 1962-63 academic year.

John Preskill and Kip S. Thorne, in the foreword to Feynman Lectures on Gravitation, 1995


Feynman the percussionist and sometime lock picker


Feynman heard [my son] Ralph and his friends drumming at the other end of the house and, of course, he went in—he was more comfortable with kids anyway. He introduced himself and they invited him in to drum. And that led to rather regular drumming by Feynman, my son, and a couple of other drop-in friends. I myself was curious about Feynman's drumming ability, so I asked Ralph one time, "Well, how good a drummer is Feynman?" He said, "Well, he picks up the rhythms all right, and he's very fast but sometimes he has a hard time getting started. But for an old guy, he's pretty good." [Laughter] I informed Ralph that he had just spoken of the capabilities of possibly the one person in the world who knew more about how everything in the universe worked than anyone else on Earth at that moment.

Robert Leighton, William L. Valentine Professor of Physics, Emeritus
Ralph Leighton is the co-author with Feynman of two collections of Feynman's reminiscences: Surely You're Joking, Mr. Feynman: Adventures of a Curious Character, (Norton, 1985), and What Do You Care What Other People Think?: Further Adventures of a Curious Character, (Norton, 1988).


Helen Tuck (Feynman's secretary from 1972–1988), in this excerpt from an unpublished article, recounts a story Feynman told her of an incident that took place when he traveled to a conference in Austin, Texas.

Unfortunately, his plane arrived in Austin in the late evening, so by the time his cab arrived at the motel/conference center it was quite dark. What he didn’t notice was that it had been a very long drive. He checked into the motel office, was directed to his room—which was a very long way from the office—unlocked the door, and entered into an elegant suite. He took a look around and decided it was much too fancy for him, so called the office and said he wanted a smaller room. They didn’t have a smaller room available. He said then he would leave, but since it was so far to the office he was just going to leave the key in the room, and with that he

grabbed his bag and left. Trouble was, when he got outside and really took a look around he realized he was in the middle of nowhere. But he had left the key in the room and had too much pride to go back to the office.

He started walking, sure there would be something down the road. There wasn’t. When he finally realized he was really stuck, he simply walked off the road and through a hedge, and proceeded to curl up and go to sleep on the ground. He hadn’t worn a jacket and it was getting quite cold, but he knew his wife had packed a sweater.

However, it was too dark for him to work the combination on his suitcase, so of course he had to sit there and pick the lock. Which he did successfully, got his sweater, and spent the rest of the night sleeping as best he could.


In his own words

The first principle is that you must not fool yourself—and you are the easiest person to fool. So, you have to be very careful about that. After you’ve not fooled yourself, it’s easy not to fool other scientists. You just have to be honest in a conventional way after that. …

It’s a kind of scientific integrity, a principle of scientific thought that corresponds to a kind of utter honesty—a kind of leaning over backwards. For example, if you’re doing an experiment, you should report everything that you think might make it invalid—not only what you think is right about it: other causes that could possibly explain your results; and things you thought of that you’ve eliminated by some other experiment, and how they worked—to make sure the other fellow can tell they have been eliminated.

Details that could throw doubt on your interpretation must be given, if you know them. You must do the best you can—if you know anything at all wrong, or possibly wrong—to explain it. If you make a theory, for example, and advertise it, or put it out, then you must also put down all the facts that disagree with it, as well as those that agree with it. There is also a more subtle problem. When you have put a lot of ideas together to make an elaborate theory, you want to make sure, when explaining what it fits, that those things it fits are not just the things that gave you the idea for the theory; but that the finished theory makes something else come out right, in addition.

In summary, the idea is to try to give all of the information to help others to judge the value of your contribution; not just the information that leads to judgment in one particular direction or another.

Richard Feynman, 1974 Caltech Commencement Address