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My friend Richard Feynman | Leonard Susskind | TEDxCaltech

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    I can't see the audience, and I hate that.
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    How many great grandparents
    are there in the audience?
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    Damn it, I can't see anything.
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    You're probably wondering why I'm sitting.
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    The answer is,
    because I'm a great-grandfather.
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    Not a good grandfather,
    a great grandfather.
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    (Laughter)
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    And, as everybody knows,
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    great grandparents get to do
    any damn thing they please.
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    Including following my own
    grandfather's advice,
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    which was, whenever you give a talk
    to a thousand people
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    about Richard Feynman, sustain yourself.
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    (Laughter)
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    (Applause)
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    This is an extremely slick operation
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    and I'm not a slick man.
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    I don't use these things.
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    I decided when I was asked to do this
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    that what I really wanted to talk about
    was my friend, Richard Feynman.
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    I was one of the fortunate few
    that really did get to know him
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    and enjoyed his presence.
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    And I'm going to tell you
    about the Richard Feynman that I knew.
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    I'm sure there are people here
    who could tell you
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    about the Richard Feynman they knew,
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    and it would probably be
    a different Richard Feynman.
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    Richard Feynman was a very complex man.
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    He was a man of many, many parts.
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    He was, of course, foremost,
    a very, very, very great scientist.
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    He was an actor. You saw him act.
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    I also had the good fortune
    to be in those lectures,
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    up in the balcony.
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    They were fantastic.
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    He was a philosopher.
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    He was a drum player.
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    He was a teacher par excellence.
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    Richard Feynman was also a showman,
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    an enormous showman.
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    He was brash, irreverent.
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    He was full of macho,
    a kind of macho one-upmanship.
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    He loved intellectual battle.
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    He had a gargantuan ego.
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    But the man had, somehow,
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    a lot of room at the bottom.
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    And what I mean by that
    is a lot of room, in my case --
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    I can't speak for anybody else,
    but in my case --
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    a lot of room for another big ego.
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    Well, not as big as his,
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    but fairly big.
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    I always felt good with Dick Feynman.
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    It was always fun to be with him.
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    He always made me feel smart.
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    How can somebody like that
    make you feel smart?
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    Somehow he did.
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    He made me feel smart.
    He made me feel he was smart.
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    He made me feel we were both smart,
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    and the two of us could solve
    any problem whatever.
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    And in fact, we did sometimes
    do physics together.
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    We never published a paper together,
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    but we did have a lot of fun.
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    He loved to win,
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    win these little macho games
    we would sometimes play.
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    And he didn't only play them with me,
    but with all sorts of people.
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    He would almost always win.
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    But when he didn't win, when he lost,
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    he would laugh and seem
    to have just as much fun
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    as if he had won.
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    I remember once he told me a story
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    about a joke the students played on him.
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    I think it was for his birthday --
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    they took him for lunch
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    to a sandwich place in Pasadena.
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    It may still exist; I don't know.
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    Celebrity sandwiches was their thing.
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    You could get a Marilyn Monroe sandwich.
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    You could get a Humphrey Bogart sandwich.
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    The students went there in advance,
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    and arranged that they'd all order
    Feynman sandwiches.
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    One after another, they came in
    and ordered Feynman sandwiches.
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    Feynman loved this story.
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    He told me this story,
    and he was really happy and laughing.
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    When he finished the story, I said to him,
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    "Dick, I wonder what
    would be the difference
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    between a Feynman sandwich
    and a Susskind sandwich."
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    And without skipping a beat at all,
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    he said, "Well, they'd be about the same.
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    The only difference is a Susskind
    sandwich would have a lot more ham."
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    "Ham" as in bad actor.
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    (Laughter)
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    Well, I happened to have been
    very quick that day,
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    and I said, "Yeah,
    but a lot less baloney."
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    (Laughter)
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    (Applause)
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    The truth of the matter
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    is that a Feynman sandwich
    had a load of ham,
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    but absolutely no baloney.
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    What Feynman hated worse
    than anything else
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    was intellectual pretense --
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    phoniness,
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    false sophistication, jargon.
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    I remember sometime during the mid-'80s,
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    Dick and I and Sidney Coleman
    would meet a couple of times
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    up in San Francisco --
    at some very rich guy's house --
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    up in San Francisco for dinner.
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    And the last time the rich guy invited us,
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    he also invited a couple of philosophers.
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    These guys were philosophers of mind.
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    Their specialty was the philosophy
    of consciousness.
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    And they were full of all kinds of jargon.
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    I'm trying to remember the words --
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    "monism," "dualism,"
    categories all over the place.
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    I didn't know what those meant, neither
    did Dick or Sydney, for that matter.
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    Sydney, who was better educated
    than most of us.
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    And what did we talk about?
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    Well, what do you talk about
    when you talk about minds?
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    There's one obvious thing to talk about:
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    Can a machine become a mind?
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    Can you build a machine
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    that thinks like a human being
    that is conscious?
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    We sat around and talked about this --
    we of course never resolved it.
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    But the trouble with the philosophers
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    is that they were philosophizing
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    when they should have been
    science-ophizing.
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    It's a scientific question, after all.
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    And this was a very, very
    dangerous thing to do
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    around Dick Feynman.
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    (Laughter)
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    Feynman let them have it --
    both barrels, right between the eyes.
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    It was brutal; it was funny --
    ooh, it was funny.
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    But it was really brutal.
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    He really popped their balloon.
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    But the amazing thing was --
    Feynman had to leave a little early;
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    he wasn't feeling too well,
    so he left a little bit early.
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    And Sidney and I were left there
    with the two philosophers.
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    And the amazing thing
    is these guys were flying.
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    They were so happy.
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    They had met the great man;
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    they had been instructed by the great man;
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    they had an enormous amount of fun
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    having their faces shoved in the mud ...
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    And it was something special.
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    I realized there was something
    just extraordinary about Feynman,
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    even when he did what he did.
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    So yes - he did not like
    intellectual pretense.
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    Dick -- he was my friend;
    I did call him Dick --
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    Dick and I had a little bit of a rapport.
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    I think it may have been a special
    rapport that he and I had.
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    We liked each other;
    we liked the same kind of things.
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    I also like the intellectual macho games.
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    Sometimes I would win,
    mostly he would win,
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    but we both enjoyed them.
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    And Dick became convinced at some point
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    that he and I had
    some kind of similarity of personality.
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    I don't think he was right.
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    I think the only point
    of similarity between us
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    is we both like to talk about ourselves.
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    But he was convinced of this.
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    And the man was incredibly curious.
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    And he wanted to understand
    what it was and why it was
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    that there was this funny connection.
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    And one day, we were walking.
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    We were in France, in Les Houches.
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    We were up in the mountains, 1976.
    Up in the mountains.
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    And Feynman said to me, "Leonardo ..."
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    The reason he called me "Leonardo"
    is because we were in Europe,
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    and he was practicing his French.
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    (Laughter)
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    And he said, "Leonardo,
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    were you closer to your mother
    or your father when you were a kid?"
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    I said, "Well, my real hero was my father.
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    He was a working man,
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    had a fifth-grade education.
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    He was a master mechanic,
    and he taught me how to use tools.
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    He taught me all sorts of things
    about mechanical things.
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    He even taught me the Pythagorean theorem.
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    He didn't call it the hypotenuse,
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    he called it the shortcut distance."
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    And Feynman's eyes just opened up.
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    He went off like a lightbulb.
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    And he said that he had had
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    basically exactly the same
    relationship with his father.
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    In fact, he had been convinced at one time
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    that to be a good physicist,
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    it was very important to have had
    that kind of relationship
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    with your father.
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    I apologize for the sexist
    conversation here,
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    but this is the way it really happened.
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    He said he had been absolutely
    convinced that this was necessary,
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    a necessary part of the growing up
    of a young physicist.
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    Being Dick, he, of course,
    wanted to check this.
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    He wanted to go out and do an experiment.
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    (Laughter)
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    Well, he did.
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    He went out and did an experiment.
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    He asked all his friends
    that he thought were good physicists,
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    "Was it your mom or your pop
    that influenced you?"
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    And to a man -
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    they were all men,
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    and to a man, every single
    one of them said,
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    "My mother."
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    (Laughter)
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    There went that theory,
    down the trash can of history.
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    (Laughter)
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    But he was very excited
    that he had finally met somebody
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    who had the same experience
    with his father
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    as he had with his father.
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    And for some time, he was convinced
    this was the reason we got along so well.
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    I don't know. Maybe. Who knows?
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    But let me tell you a little bit
    about Feynman the physicist.
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    Feynman's style --
    no, "style" is not the right word.
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    "Style" makes you think
    of the bow tie he might have worn,
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    or the suit he was wearing.
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    It's something much deeper than that,
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    but I can't think of another word for it.
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    Feynman's scientific style
    was always to look for the simplest,
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    most elementary solution
    to a problem that was possible.
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    If it wasn't possible,
    you had to use something fancier.
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    No doubt, part of this
    was his great joy and pleasure
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    in showing people that he could
    think more simply than they could.
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    But he also deeply believed,
    he truly believed,
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    that if you couldn't explain
    something simply,
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    you didn't understand it.
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    In the 1950s, people
    were trying to figure out
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    how superfluid helium worked.
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    There was a theory.
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    It was due to a Russian
    mathematical physicist.
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    It was a complicated theory;
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    I'll tell you what it was soon enough.
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    It was a terribly complicated theory,
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    full of very difficult
    integrals and formulas
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    and mathematics and so forth.
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    And it sort of worked,
    but it didn't work very well.
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    The only way it worked
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    is when the helium atoms
    were very, very far apart.
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    They had to be.
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    And unfortunately,
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    the helium atoms in liquid helium
    are right on top of each other.
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    Feynman decided, as a sort
    of amateur helium physicist,
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    that he would try to figure it out.
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    He had an idea, a very clear idea.
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    He would try to figure out
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    what the quantum wave function
    of this huge number of atoms looked like.
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    He would try to visualize it,
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    guided by a small number
    of simple principles.
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    The small number of simple principles
    were very, very simple.
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    The first one was that when
    helium atoms touch each other,
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    they repel.
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    The implication of that is that
    the wave function has to go to zero,
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    it has to vanish when the helium
    atoms touch each other.
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    The other fact
    is that in the ground state --
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    the lowest energy state
    of a quantum system --
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    the wave function is always very smooth;
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    it has the minimum number of wiggles.
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    So he sat down --
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    and I imagine he had nothing more
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    than a simple piece
    of paper and a pencil --
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    and he tried to write down,
    and did write down,
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    the simplest function
    that he could think of,
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    which had the boundary conditions
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    that the wave function
    vanish when things touch
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    and is smooth in between.
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    He wrote down a simple thing --
    so simple, in fact,
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    that I suspect a really smart
    high-school student
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    who didn't even have calculus
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    could understand what he wrote down.
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    The thing was, that simple thing
    that he wrote down
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    explained everything that was known
    at the time about liquid helium,
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    and then some.
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    I've always wondered
    whether the professionals --
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    the real professional helium physicists --
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    were just a little bit
    embarrassed by this.
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    They had their super-powerful technique,
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    and they couldn't do as well.
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    Incidentally, I'll tell you
    what that super-powerful technique was.
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    It was the technique of Feynman diagrams.
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    (Laughter)
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    He did it again in 1968.
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    In 1968, in my own university --
    I wasn't there at the time --
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    they were exploring
    the structure of the proton.
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    The proton is obviously made
    of a whole bunch of little particles;
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    this was more or less known.
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    And the way to analyze it was,
    of course, Feynman diagrams.
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    That's what Feynman diagrams
    were constructed for --
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    to understand particles.
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    The experiments that were going on
    were very simple:
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    you simply take the proton,
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    and you hit it really sharply
    with an electron.
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    This was the thing
    the Feynman diagrams were for.
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    The only problem was that
    Feynman diagrams are complicated.
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    They're difficult integrals.
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    If you could do all of them,
    you would have a very precise theory,
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    but you couldn't --
    they were just too complicated.
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    People were trying to do them.
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    You could do a one-loop diagram.
    Don't worry about one loop.
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    One loop, two loops --
    maybe you could do a three-loop diagram,
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    but beyond that, you couldn't do anything.
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    Feynman said, "Forget all of that.
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    Just think of the proton
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    as an assemblage, a swarm,
    of little particles."
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    He called them "partons."
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    He said, "Just think of it as a swarm
    of partons moving real fast."
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    Because they're moving real fast,
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    relativity says the internal
    motions go very slow.
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    The electron hits it suddenly --
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    it's like taking a very sudden
    snapshot of the proton.
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    What do you see?
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    You see a frozen bunch of partons.
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    They don't move,
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    and because they don't move
    during the course of the experiment,
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    you don't have to worry
    about how they're moving.
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    You don't have to worry
    about the forces between them.
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    You just get to think of it
    as a population of frozen partons."
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    This was the key to analyzing
    these experiments.
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    Extremely effective.
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    Somebody said the word
    "revolution" is a bad word.
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    I suppose it is,
    so I won't say "revolution,"
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    but it certainly evolved very, very deeply
    our understanding of the proton,
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    and of particles beyond that.
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    Well, I had some more
    that I was going to tell you
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    about my connection with Feynman,
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    what he was like,
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    but I see I have exactly half a minute.
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    So I think I'll just finish up by saying:
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    I actually don't think
    Feynman would have liked this event.
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    I think he would have said,
    "I don't need this."
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    But ...
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    (Laughter)
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    How should we honor Feynman?
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    How should we really honor Feynman?
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    I think the answer
    is we should honor Feynman
  • 15:18 - 15:22
    by getting as much baloney
    out of our own sandwiches
  • 15:22 - 15:23
    as we can.
  • 15:24 - 15:25
    Thank you.
  • 15:25 - 15:28
    (Applause)
Title:
My friend Richard Feynman | Leonard Susskind | TEDxCaltech
Description:

What's it like to be pals with a genius? Onstage at TEDxCaltech, physicist Leonard Susskind spins a few stories about his friendship with the legendary Richard Feynman, discussing his unconventional approach to problems both serious and ... less so.

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Video Language:
English
Team:
TED
Project:
TEDxTalks
Duration:
15:42

English subtitles

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