0:00:00.928,0:00:02.785 I decided when I was asked to do this 0:00:02.809,0:00:06.507 that what I really wanted to talk about[br]was my friend, Richard Feynman. 0:00:06.531,0:00:09.976 I was one of the fortunate few[br]that really did get to know him 0:00:10.000,0:00:11.410 and enjoyed his presence. 0:00:12.000,0:00:15.503 And I'm going to tell you[br]about the Richard Feynman that I knew. 0:00:15.527,0:00:17.826 I'm sure there are people here[br]who could tell you 0:00:17.850,0:00:19.567 about the Richard Feynman they knew, 0:00:19.591,0:00:22.116 and it would probably be[br]a different Richard Feynman. 0:00:22.140,0:00:24.123 Richard Feynman was a very complex man. 0:00:24.147,0:00:26.123 He was a man of many, many parts. 0:00:26.464,0:00:31.210 He was, of course, foremost,[br]a very, very, very great scientist. 0:00:31.798,0:00:33.976 He was an actor. You saw him act. 0:00:34.000,0:00:37.658 I also had the good fortune[br]to be in those lectures, 0:00:37.682,0:00:38.976 up in the balcony. 0:00:39.536,0:00:40.742 They were fantastic. 0:00:41.885,0:00:43.060 He was a philosopher. 0:00:43.631,0:00:44.801 He was a drum player. 0:00:44.825,0:00:46.784 He was a teacher par excellence. 0:00:48.483,0:00:51.140 Richard Feynman was also a showman, 0:00:51.164,0:00:52.727 an enormous showman. 0:00:52.751,0:00:55.186 He was brash, irreverent. 0:00:56.186,0:01:00.976 He was full of macho,[br]a kind of macho one-upmanship. 0:01:01.455,0:01:05.058 He loved intellectual battle. 0:01:05.405,0:01:08.054 He had a gargantuan ego. 0:01:09.157,0:01:12.633 But the man had, somehow, 0:01:12.657,0:01:15.109 a lot of room at the bottom. 0:01:15.133,0:01:19.863 And what I mean by that[br]is a lot of room, in my case -- 0:01:19.887,0:01:22.976 I can't speak for anybody else,[br]but in my case -- 0:01:23.000,0:01:26.279 a lot of room for another big ego. 0:01:26.303,0:01:27.693 Well, not as big as his, 0:01:27.717,0:01:29.597 but fairly big. 0:01:30.890,0:01:32.779 I always felt good with Dick Feynman. 0:01:33.136,0:01:35.110 It was always fun to be with him. 0:01:35.586,0:01:37.348 He always made me feel smart. 0:01:37.753,0:01:39.960 How can somebody like that[br]make you feel smart? 0:01:39.984,0:01:41.150 Somehow he did. 0:01:41.174,0:01:43.634 He made me feel smart.[br]He made me feel he was smart. 0:01:43.658,0:01:45.609 He made me feel we were both smart, 0:01:45.633,0:01:48.975 and the two of us could solve[br]any problem whatever. 0:01:50.083,0:01:53.091 And in fact, we did sometimes[br]do physics together. 0:01:53.115,0:01:55.160 We never published a paper together, 0:01:55.184,0:01:56.644 but we did have a lot of fun. 0:01:58.760,0:01:59.976 He loved to win, 0:02:00.679,0:02:03.379 win these little macho games[br]we would sometimes play. 0:02:03.403,0:02:06.667 And he didn't only play them with me,[br]but with all sorts of people. 0:02:06.691,0:02:08.528 He would almost always win. 0:02:08.552,0:02:11.615 But when he didn't win, when he lost, 0:02:11.639,0:02:14.276 he would laugh and seem[br]to have just as much fun 0:02:14.300,0:02:15.498 as if he had won. 0:02:16.331,0:02:18.479 I remember once he told me a story 0:02:18.503,0:02:20.424 about a joke the students played on him. 0:02:20.892,0:02:23.429 I think it was for his birthday -- 0:02:23.453,0:02:24.870 they took him for lunch 0:02:24.894,0:02:29.512 to a sandwich place in Pasadena. 0:02:29.536,0:02:31.171 It may still exist; I don't know. 0:02:31.584,0:02:34.166 Celebrity sandwiches was their thing. 0:02:34.190,0:02:36.530 You could get a Marilyn Monroe sandwich. 0:02:36.554,0:02:38.855 You could get a Humphrey Bogart sandwich. 0:02:39.373,0:02:41.555 The students went there in advance, 0:02:41.579,0:02:44.977 and arranged that they'd all order[br]Feynman sandwiches. 0:02:45.001,0:02:47.988 One after another, they came in[br]and ordered Feynman sandwiches. 0:02:48.012,0:02:49.240 Feynman loved this story. 0:02:49.264,0:02:53.298 He told me this story,[br]and he was really happy and laughing. 0:02:53.322,0:02:56.072 When he finished the story, I said to him, 0:02:56.096,0:02:58.959 "Dick, I wonder what[br]would be the difference 0:02:58.983,0:03:01.976 between a Feynman sandwich[br]and a Susskind sandwich." 0:03:02.491,0:03:04.506 And without skipping a beat at all, 0:03:04.530,0:03:07.772 he said, "Well, they'd be about the same. 0:03:07.796,0:03:11.118 The only difference is a Susskind[br]sandwich would have a lot more ham." 0:03:11.142,0:03:12.827 "Ham" as in bad actor. 0:03:12.851,0:03:14.375 (Laughter) 0:03:14.399,0:03:17.809 Well, I happened to have been[br]very quick that day, 0:03:17.833,0:03:19.976 and I said, "Yeah,[br]but a lot less baloney." 0:03:20.000,0:03:22.954 (Laughter) 0:03:22.978,0:03:24.115 (Applause) 0:03:24.139,0:03:27.321 The truth of the matter 0:03:27.345,0:03:31.327 is that a Feynman sandwich[br]had a load of ham, 0:03:31.351,0:03:34.130 but absolutely no baloney. 0:03:35.645,0:03:37.918 What Feynman hated worse[br]than anything else 0:03:37.942,0:03:39.944 was intellectual pretense -- 0:03:39.968,0:03:41.197 phoniness, 0:03:41.221,0:03:43.648 false sophistication, jargon. 0:03:44.950,0:03:49.218 I remember sometime during the mid-'80s, 0:03:49.242,0:03:53.376 Dick and I and Sidney Coleman[br]would meet a couple of times 0:03:53.400,0:03:56.565 up in San Francisco --[br]at some very rich guy's house -- 0:03:56.589,0:03:58.716 up in San Francisco for dinner. 0:03:58.740,0:04:00.976 And the last time the rich guy invited us, 0:04:01.000,0:04:03.136 he also invited a couple of philosophers. 0:04:03.160,0:04:05.688 These guys were philosophers of mind. 0:04:05.712,0:04:09.076 Their specialty was the philosophy[br]of consciousness. 0:04:09.100,0:04:11.790 And they were full of all kinds of jargon. 0:04:11.814,0:04:14.210 I'm trying to remember the words -- 0:04:14.234,0:04:18.124 "monism," "dualism,"[br]categories all over the place. 0:04:18.148,0:04:21.722 I didn't know what those meant, neither[br]did Dick or Sydney, for that matter. 0:04:21.746,0:04:23.516 And what did we talk about? 0:04:23.540,0:04:26.115 Well, what do you talk about[br]when you talk about minds? 0:04:26.139,0:04:28.303 There's one obvious thing to talk about: 0:04:28.327,0:04:29.976 Can a machine become a mind? 0:04:30.578,0:04:32.307 Can you build a machine 0:04:32.331,0:04:35.413 that thinks like a human being[br]that is conscious? 0:04:35.841,0:04:39.171 We sat around and talked about this --[br]we of course never resolved it. 0:04:39.195,0:04:40.976 But the trouble with the philosophers 0:04:41.000,0:04:42.976 is that they were philosophizing 0:04:43.000,0:04:45.344 when they should have been[br]science-ophizing. 0:04:45.788,0:04:48.128 It's a scientific question, after all. 0:04:48.152,0:04:51.059 And this was a very, very[br]dangerous thing to do 0:04:51.083,0:04:52.512 around Dick Feynman. 0:04:52.536,0:04:54.020 (Laughter) 0:04:55.278,0:04:58.473 Feynman let them have it --[br]both barrels, right between the eyes. 0:04:58.497,0:05:01.568 It was brutal; it was funny --[br]ooh, it was funny. 0:05:01.592,0:05:03.305 But it was really brutal. 0:05:03.329,0:05:05.279 He really popped their balloon. 0:05:06.065,0:05:09.565 But the amazing thing was --[br]Feynman had to leave a little early; 0:05:09.589,0:05:12.691 he wasn't feeling too well,[br]so he left a little bit early. 0:05:12.715,0:05:15.609 And Sidney and I were left there[br]with the two philosophers. 0:05:15.633,0:05:18.623 And the amazing thing[br]is these guys were flying. 0:05:18.647,0:05:20.463 They were so happy. 0:05:20.828,0:05:23.082 They had met the great man; 0:05:23.106,0:05:25.534 they had been instructed by the great man; 0:05:25.558,0:05:27.499 they had an enormous amount of fun 0:05:27.523,0:05:29.708 having their faces shoved in the mud ... 0:05:30.875,0:05:33.334 And it was something special. 0:05:33.358,0:05:36.747 I realized there was something[br]just extraordinary about Feynman, 0:05:36.771,0:05:40.585 even when he did what he did. 0:05:43.414,0:05:46.088 Dick -- he was my friend;[br]I did call him Dick -- 0:05:46.112,0:05:48.798 Dick and I had a little bit of a rapport. 0:05:48.822,0:05:51.696 I think it may have been a special[br]rapport that he and I had. 0:05:51.720,0:05:54.343 We liked each other;[br]we liked the same kind of things. 0:05:54.367,0:05:57.850 I also like the intellectual macho games. 0:05:58.278,0:06:00.358 Sometimes I would win,[br]mostly he would win, 0:06:00.382,0:06:01.976 but we both enjoyed them. 0:06:02.000,0:06:04.390 And Dick became convinced at some point 0:06:04.414,0:06:08.622 that he and I had[br]some kind of similarity of personality. 0:06:09.226,0:06:10.680 I don't think he was right. 0:06:10.704,0:06:12.923 I think the only point[br]of similarity between us 0:06:12.947,0:06:15.145 is we both like to talk about ourselves. 0:06:15.169,0:06:18.010 But he was convinced of this. 0:06:18.034,0:06:21.088 And the man was incredibly curious. 0:06:21.112,0:06:24.786 And he wanted to understand[br]what it was and why it was 0:06:24.810,0:06:27.637 that there was this funny connection. 0:06:28.374,0:06:30.058 And one day, we were walking. 0:06:30.082,0:06:31.908 We were in France, in Les Houches. 0:06:31.932,0:06:35.556 We were up in the mountains, 1976. 0:06:35.580,0:06:39.838 And Feynman said to me, "Leonardo ..." 0:06:39.862,0:06:42.897 The reason he called me "Leonardo"[br]is because we were in Europe, 0:06:42.921,0:06:44.572 and he was practicing his French. 0:06:44.596,0:06:46.716 (Laughter) 0:06:46.740,0:06:49.963 And he said, "Leonardo, 0:06:49.987,0:06:53.976 were you closer to your mother[br]or your father when you were a kid?" 0:06:54.000,0:06:56.976 I said, "Well, my real hero was my father. 0:06:58.057,0:07:00.208 He was a working man, 0:07:00.232,0:07:01.885 had a fifth-grade education. 0:07:02.375,0:07:05.199 He was a master mechanic,[br]and he taught me how to use tools. 0:07:05.223,0:07:09.191 He taught me all sorts of things[br]about mechanical things. 0:07:09.215,0:07:11.246 He even taught me the Pythagorean theorem. 0:07:11.270,0:07:13.223 He didn't call it the hypotenuse, 0:07:13.247,0:07:15.315 he called it the shortcut distance." 0:07:15.855,0:07:18.632 And Feynman's eyes just opened up. 0:07:18.656,0:07:20.249 He went off like a lightbulb. 0:07:21.011,0:07:23.092 And he said that he had had 0:07:23.116,0:07:26.275 basically exactly the same[br]relationship with his father. 0:07:26.870,0:07:30.290 In fact, he had been convinced at one time 0:07:30.314,0:07:34.125 that to be a good physicist, 0:07:34.149,0:07:37.482 it was very important to have had[br]that kind of relationship 0:07:37.506,0:07:38.662 with your father. 0:07:38.686,0:07:41.692 I apologize for the sexist[br]conversation here, 0:07:41.716,0:07:43.576 but this is the way it really happened. 0:07:43.600,0:07:47.397 He said he had been absolutely[br]convinced that this was necessary, 0:07:47.421,0:07:51.060 a necessary part of the growing up[br]of a young physicist. 0:07:51.655,0:07:54.788 Being Dick, he, of course,[br]wanted to check this. 0:07:54.812,0:07:57.088 He wanted to go out and do an experiment. 0:07:57.112,0:07:58.128 (Laughter) 0:07:58.152,0:07:59.304 Well, he did. 0:07:59.328,0:08:00.986 He went out and did an experiment. 0:08:01.010,0:08:03.925 He asked all his friends[br]that he thought were good physicists, 0:08:03.949,0:08:06.294 "Was it your mom or your pop[br]that influenced you?" 0:08:06.318,0:08:08.281 They were all men, 0:08:08.305,0:08:10.935 and to a man, every single[br]one of them said, 0:08:10.959,0:08:12.183 "My mother." 0:08:12.207,0:08:15.274 (Laughter) 0:08:15.298,0:08:19.298 There went that theory,[br]down the trash can of history. 0:08:19.322,0:08:20.426 (Laughter) 0:08:20.450,0:08:23.252 But he was very excited[br]that he had finally met somebody 0:08:23.276,0:08:26.872 who had the same experience[br]with his father 0:08:26.896,0:08:28.331 as he had with his father. 0:08:28.355,0:08:32.480 And for some time, he was convinced[br]this was the reason we got along so well. 0:08:32.504,0:08:34.141 I don't know. Maybe. Who knows? 0:08:34.600,0:08:38.392 But let me tell you a little bit[br]about Feynman the physicist. 0:08:40.622,0:08:44.576 Feynman's style --[br]no, "style" is not the right word. 0:08:44.600,0:08:47.445 "Style" makes you think[br]of the bow tie he might have worn, 0:08:47.469,0:08:48.770 or the suit he was wearing. 0:08:48.794,0:08:50.713 It's something much deeper than that, 0:08:50.737,0:08:52.808 but I can't think of another word for it. 0:08:52.832,0:08:58.274 Feynman's scientific style[br]was always to look for the simplest, 0:08:58.298,0:09:02.213 most elementary solution[br]to a problem that was possible. 0:09:02.237,0:09:05.762 If it wasn't possible,[br]you had to use something fancier. 0:09:06.469,0:09:11.041 No doubt, part of this[br]was his great joy and pleasure 0:09:11.065,0:09:14.497 in showing people that he could[br]think more simply than they could. 0:09:14.837,0:09:17.996 But he also deeply believed,[br]he truly believed, 0:09:18.020,0:09:20.260 that if you couldn't explain[br]something simply, 0:09:20.284,0:09:21.815 you didn't understand it. 0:09:23.140,0:09:26.393 In the 1950s, people[br]were trying to figure out 0:09:26.417,0:09:28.393 how superfluid helium worked. 0:09:29.313,0:09:30.489 There was a theory. 0:09:30.513,0:09:32.924 It was due to a Russian[br]mathematical physicist. 0:09:32.948,0:09:34.358 It was a complicated theory; 0:09:34.382,0:09:36.493 I'll tell you what it was soon enough. 0:09:36.517,0:09:38.365 It was a terribly complicated theory, 0:09:38.389,0:09:41.226 full of very difficult[br]integrals and formulas 0:09:41.250,0:09:43.075 and mathematics and so forth. 0:09:43.600,0:09:46.837 And it sort of worked,[br]but it didn't work very well. 0:09:46.861,0:09:48.203 The only way it worked 0:09:48.227,0:09:51.446 is when the helium atoms[br]were very, very far apart. 0:09:51.470,0:09:54.183 And unfortunately, 0:09:54.207,0:09:57.365 the helium atoms in liquid helium[br]are right on top of each other. 0:09:57.389,0:10:00.730 Feynman decided, as a sort[br]of amateur helium physicist, 0:10:00.754,0:10:03.004 that he would try to figure it out. 0:10:03.028,0:10:05.432 He had an idea, a very clear idea. 0:10:05.456,0:10:06.850 He would try to figure out 0:10:06.874,0:10:11.950 what the quantum wave function[br]of this huge number of atoms looked like. 0:10:11.974,0:10:13.621 He would try to visualize it, 0:10:13.645,0:10:16.576 guided by a small number[br]of simple principles. 0:10:16.600,0:10:19.576 The small number of simple principles[br]were very, very simple. 0:10:19.600,0:10:22.977 The first one was that when[br]helium atoms touch each other, 0:10:23.001,0:10:24.309 they repel. 0:10:24.333,0:10:27.731 The implication of that is that[br]the wave function has to go to zero, 0:10:27.755,0:10:30.840 it has to vanish when the helium[br]atoms touch each other. 0:10:30.864,0:10:33.173 The other fact[br]is that in the ground state -- 0:10:33.197,0:10:35.934 the lowest energy state[br]of a quantum system -- 0:10:35.958,0:10:39.229 the wave function is always very smooth; 0:10:39.253,0:10:41.348 it has the minimum number of wiggles. 0:10:41.372,0:10:42.900 So he sat down -- 0:10:42.924,0:10:45.195 and I imagine he had nothing more 0:10:45.219,0:10:47.632 than a simple piece[br]of paper and a pencil -- 0:10:47.656,0:10:49.896 and he tried to write down,[br]and did write down, 0:10:49.920,0:10:52.215 the simplest function[br]that he could think of, 0:10:52.239,0:10:54.216 which had the boundary conditions 0:10:54.240,0:10:56.704 that the wave function[br]vanish when things touch 0:10:56.728,0:10:58.441 and is smooth in between. 0:10:59.233,0:11:01.972 He wrote down a simple thing --[br]so simple, in fact, 0:11:01.996,0:11:05.123 that I suspect a really smart[br]high-school student 0:11:05.147,0:11:06.576 who didn't even have calculus 0:11:06.600,0:11:08.533 could understand what he wrote down. 0:11:09.077,0:11:12.226 The thing was, that simple thing[br]that he wrote down 0:11:12.250,0:11:15.791 explained everything that was known[br]at the time about liquid helium, 0:11:15.815,0:11:17.088 and then some. 0:11:17.504,0:11:20.481 I've always wondered[br]whether the professionals -- 0:11:20.505,0:11:22.566 the real professional helium physicists -- 0:11:22.590,0:11:24.757 were just a little bit[br]embarrassed by this. 0:11:25.162,0:11:27.831 They had their super-powerful technique, 0:11:27.855,0:11:29.631 and they couldn't do as well. 0:11:29.655,0:11:33.782 Incidentally, I'll tell you[br]what that super-powerful technique was. 0:11:33.806,0:11:36.355 It was the technique of Feynman diagrams. 0:11:36.379,0:11:38.236 (Laughter) 0:11:38.260,0:11:41.014 He did it again in 1968. 0:11:41.521,0:11:46.507 In 1968, in my own university --[br]I wasn't there at the time -- 0:11:46.531,0:11:49.103 they were exploring[br]the structure of the proton. 0:11:49.497,0:11:53.113 The proton is obviously made[br]of a whole bunch of little particles; 0:11:53.137,0:11:55.077 this was more or less known. 0:11:55.522,0:11:58.858 And the way to analyze it was,[br]of course, Feynman diagrams. 0:11:58.882,0:12:01.423 That's what Feynman diagrams[br]were constructed for -- 0:12:01.447,0:12:02.716 to understand particles. 0:12:03.234,0:12:05.846 The experiments that were going on[br]were very simple: 0:12:05.870,0:12:07.205 you simply take the proton, 0:12:07.229,0:12:09.839 and you hit it really sharply[br]with an electron. 0:12:09.863,0:12:12.554 This was the thing[br]the Feynman diagrams were for. 0:12:12.991,0:12:17.054 The only problem was that[br]Feynman diagrams are complicated. 0:12:17.078,0:12:18.618 They're difficult integrals. 0:12:18.642,0:12:21.813 If you could do all of them,[br]you would have a very precise theory, 0:12:21.837,0:12:24.414 but you couldn't --[br]they were just too complicated. 0:12:25.313,0:12:26.774 People were trying to do them. 0:12:26.798,0:12:29.718 You could do a one-loop diagram.[br]Don't worry about one loop. 0:12:29.742,0:12:32.747 One loop, two loops --[br]maybe you could do a three-loop diagram, 0:12:32.771,0:12:34.825 but beyond that, you couldn't do anything. 0:12:34.849,0:12:36.493 Feynman said, "Forget all of that. 0:12:36.517,0:12:37.988 Just think of the proton 0:12:38.012,0:12:42.345 as an assemblage, a swarm,[br]of little particles." 0:12:42.369,0:12:44.020 He called them "partons." 0:12:44.044,0:12:49.747 He said, "Just think of it as a swarm[br]of partons moving real fast." 0:12:49.771,0:12:51.858 Because they're moving real fast, 0:12:52.996,0:12:57.098 relativity says the internal[br]motions go very slow. 0:12:57.821,0:12:59.433 The electron hits it suddenly -- 0:12:59.457,0:13:03.514 it's like taking a very sudden[br]snapshot of the proton. 0:13:04.153,0:13:05.308 What do you see? 0:13:05.332,0:13:09.366 You see a frozen bunch of partons. 0:13:09.390,0:13:10.572 They don't move, 0:13:10.596,0:13:13.652 and because they don't move[br]during the course of the experiment, 0:13:13.676,0:13:15.985 you don't have to worry[br]about how they're moving. 0:13:16.009,0:13:18.615 You don't have to worry[br]about the forces between them. 0:13:18.639,0:13:23.828 You just get to think of it[br]as a population of frozen partons." 0:13:24.314,0:13:27.778 This was the key to analyzing[br]these experiments. 0:13:27.802,0:13:30.576 Extremely effective. 0:13:30.987,0:13:33.489 Somebody said the word[br]"revolution" is a bad word. 0:13:33.513,0:13:35.654 I suppose it is,[br]so I won't say "revolution," 0:13:35.678,0:13:41.180 but it certainly evolved very, very deeply[br]our understanding of the proton, 0:13:41.204,0:13:43.000 and of particles beyond that. 0:13:43.370,0:13:45.988 Well, I had some more[br]that I was going to tell you 0:13:46.012,0:13:47.669 about my connection with Feynman, 0:13:47.693,0:13:48.867 what he was like, 0:13:48.891,0:13:51.195 but I see I have exactly half a minute. 0:13:51.219,0:13:55.146 So I think I'll just finish up by saying: 0:13:55.170,0:13:57.966 I actually don't think[br]Feynman would have liked this event. 0:13:57.990,0:14:02.279 I think he would have said,[br]"I don't need this." 0:14:02.882,0:14:04.032 But ... 0:14:04.056,0:14:05.064 (Laughter) 0:14:05.088,0:14:06.446 How should we honor Feynman? 0:14:06.470,0:14:08.152 How should we really honor Feynman? 0:14:08.176,0:14:11.320 I think the answer[br]is we should honor Feynman 0:14:11.344,0:14:15.306 by getting as much baloney[br]out of our own sandwiches 0:14:15.330,0:14:16.576 as we can. 0:14:16.941,0:14:18.092 Thank you. 0:14:18.116,0:14:21.317 (Applause)