Surely You're Joking, Mr. Feynman! (4 page)

My father and mother happened to come up that morning to see how their son was doing in Boston, and the fraternity kept putting them off until we came back from being kidnapped. I was so bedraggled and dirty from struggling so hard to escape and from lack of sleep that they were really horrified to discover what their son looked like at MIT!

I had also gotten a stiff neck, and I remember standing in line for inspection that afternoon at ROTC, not being able to look straight forward. The commander grabbed my head and turned it, shouting, “Straighten up!”

I winced, as my shoulders went at an angle: “I can’t help it, sir!

“Oh, excuse _me_!” he said, apologetically.

Anyway, the fact that I fought so long and hard not to be tied up gave me a terrific reputation, and I never had to worry about that sissy business again–a tremendous relief.

I often listened to my roommates–they were both seniors–studying for their theoretical physics course. One day they were working pretty hard on something that seemed pretty clear to me, so I said, “Why don’t you use the Baronallai’s equation?”

“What’s that!” they exclaimed. “What are you talking about!”

I explained to them what I meant and how it worked in this case, and it solved the problem. It turned out it was Bernoulli’s equation that I meant, but I had read all this stuff in the encyclopedia without talking to anybody about it, so I didn’t know how to pronounce anything.

But my roommates were very excited, and from then on they discussed their physics problems with me–I wasn’t so lucky with many of them–and the next year, when I took the course, I advanced rapidly. That was a very good way to get educated, working on the senior problems and learning how to pronounce things.

I liked to go to a place called the Raymor and Playmore Ballroom–two ballrooms that were connected together–on Tuesday nights. My fraternity brothers didn’t go to these “open” dances; they preferred their own dances, where the girls they brought were upper crust ones they had met “properly.” I didn’t care, when I met somebody, where they were from, or what their background was, so I would go to these dances–even though my fraternity brothers disapproved (I was a junior by this time, and they couldn’t stop me)–and I had a very good time.

One time I danced with a certain girl a few times, and didn’t say much. Finally, she said to me, “Who hants vewwy nice-ee.”

I couldn’t quite make it out–she had some difficulty in speech–but I thought she said, “You dance very nicely.”

“Thank you,” I said. “It’s been an honor.”

We went over to a table where a friend of hers had found a boy she was dancing with and we sat, the four of us, together. One girl was very hard of hearing, and the other girl was nearly deaf.

When the two girls conversed they would do a large amount of signaling very rapidly back and forth, and grunt a little bit. It didn’t bother me; the girl danced well, and she was a nice person.

After a few more dances, we’re sitting at the table again, and there’s a large amount of signaling back and forth, back and forth, back and forth, until finally she says something to me which I gathered means, she’d like us to take them to some hotel.

I ask the other guy if he wants to go.

“What do they want us to go to this hotel for?” he asks.

“Hell, I don’t know. We didn’t talk well enough!” But I don’t _have_ to know. It’s just fun, seeing what’s going to happen; it’s an adventure!

The other guy’s afraid, so he says no. So I take the two girls in a taxi to the hotel, and discover that there’s a dance organized by the deaf and dumb, believe it or not. They all belonged to a club. It turns out many of them can feel the rhythm enough to dance to the music and applaud the band at the end of each number.

It was very, very interesting! I felt as if I was in a foreign country and couldn’t speak the language: I could speak, but nobody could hear me. Everybody was talking with signs to everybody else, and I couldn’t understand anything! I asked my girl to teach me some signs and I learned a few, like you learn a foreign language, just for fun.

Everyone was so happy and relaxed with each other, making jokes and smiling all the time; they didn’t seem to have any real difficulty of any kind communicating with each other. It was the same as with any other language, except for one thing: as they’re making signs to each other, their heads were always turning from one side to the other. I realized what that was. When someone wants to make a side remark or interrupt you, he can’t yell, “Hey, Jack!” He can only make a signal, which you won’t catch unless you’re in the habit of looking around all the time.

They were completely comfortable with each other. It was _my_ problem to be comfortable. It was a wonderful experience.

The dance went on for a long time, and when it closed down we went to a cafeteria. They were all ordering things by pointing to them. I remember somebody asking in signs, “Where-are-you-from?” and my girl spelling out “N-e-w Y-o-r-k.” I still remember a guy signing to me “Good sport!”–he holds his thumb up, and then touches an imaginary lapel, for “sport.” It’s a nice system.

Everybody was sitting around, making jokes, and getting me into their world very nicely. I wanted to buy a bottle of milk, so I went up to the guy at the counter and mouthed the word “milk” without saying anything.

The guy didn’t understand.

I made the symbol for “milk,” which is two fists moving as if you’re milking a cow, and he didn’t catch that either.

I tried to point to the sign that showed the price of milk, but he still didn’t catch on.

Finally, some stranger nearby ordered milk, and I pointed to it.

“Oh! Milk!” he said, as I nodded my head yes.

He handed me the bottle, and I said, “Thank you very much!”

“You SON of a GUN!” he said, smiling.

I often liked to play tricks on people when I was at MIT. One time, in mechanical drawing class, some joker picked up a French curve (a piece of plastic for drawing smooth curves–a curly, funny-looking thing) and said, “I wonder if the curves on this thing have some special formula?”

I thought for a moment and said, “Sure they do. The curves are very special curves. Lemme show ya,” and I picked up my French curve and began to turn it slowly. “The French curve is made so that at the lowest point on each curve, no matter how you turn it, the tangent is horizontal.”

All the guys in the class were holding their French curve up at different angles, holding their pencil up to it at the lowest point and laying it along, and discovering that, sure enough, the tangent is horizontal. They were all excited by this “discovery”–even though they had already gone through a certain amount of calculus and had already “learned” that the derivative (tangent) of the minimum (lowest point) of _any_ curve is zero (horizontal). They didn’t put two and two together. They didn’t even know what they “knew.”

I don’t know what’s the matter with people: they don’t learn by understanding; they learn by some other way–by rote, or something. Their knowledge is so fragile!

I did the same kind of trick four years later at Princeton when I was talking with an experienced character, an assistant of Einstein, who was surely working with gravity all the time. I gave him a problem: You blast off in a rocket which has a clock on board, and there’s a clock on the ground. The idea is that you have to be back when the clock on the ground says one hour has passed. Now you want it so that when you come back, your clock is as far ahead as possible. According to Einstein, if you go very high, your clock will go faster, because the higher something is in a gravitational field, the faster its clock goes. But if you try to go too high, since you’ve only got an hour, you have to go so fast to get there that the speed slows your clock down. So you can’t go too high. The question is, exactly what program of speed and height should you make so that you get the maximum time on your clock?

This assistant of Einstein worked on it for quite a bit before he realized that the answer is the real motion of matter. If you shoot something up in a normal way, so that the time it takes the shell to go up and come down is an hour, that’s the correct motion. It’s the fundamental principle of Einstein’s gravity–that is, what’s called the “proper time” is at a maximum for the actual curve. But when I put it to him, about a rocket with a clock, he didn’t recognize it. It was just like the guys in mechanical drawing class, but this time it wasn’t dumb freshmen. So this kind of fragility is, in fact, fairly common, even with more learned people.

When I was a junior or senior I used to eat at a certain restaurant in Boston. I went there by myself, often on successive evenings. People got to know me, and I had the same waitress all the time.

I noticed that they were always in a hurry, rushing around, so one day, just for fun, I left my tip, which was usually ten cents (normal for those days), in two nickels, under two glasses: I filled each glass to the very top, dropped a nickel in, and with a card over it, turned it over so it was upside down on the table. Then I slipped out the card (no water leaks out because no air can come in–the rim is too close to the table for that).

I put the tip under two glasses because I knew they were always in a hurry. If the tip was a dime in one glass, the waitress, in her haste to get the table ready for the next customer, would pick up the glass, the water would spill out, and that would be the end of it. But after she does that with the first glass, what the hell is she going to do with the second one? She can’t just have the nerve to lift it up now!

On the way out I said to my waitress, “Be careful, Sue. There’s something funny about the glasses you gave me– they’re filled in on the top, and there’s a hole on the bottom!”

The next day I came back, and I had a new waitress. My regular waitress wouldn’t have anything to do with me. “Sue’s very angry at you,” my new waitress said. “After she picked up the first glass and water went all over the place, she called the boss out. They studied it a little bit, but they couldn’t spend all day figuring out what to do, so they finally picked up the other one, and water went out _again_, all over the floor. It was a terrible mess; Sue slipped later in the water. They’re _all_ mad at you.”

I laughed.

She said, “It’s not funny! How would _you_ like it if someone did that to you–what would _you_ do?”

“I’d get a soup plate and then slide the glass very carefully over to the edge of the table, and let the water run into the soup plate–it doesn’t have to run onto the floor. Then I’d take the nickel out.”

“Oh, that’s a goood idea,” she said.

That evening I left my tip under a coffee cup, which I left upside down on the table.

The next night I came and I had the same new waitress.

“What’s the idea of leaving the cup upside down last time?”

“Well, I thought that even though you were in a hurry, you’d have to go back into the kitchen and get a soup plate; then you’d have to _sloooowly_ and carefully slide the cup over to the edge of the table . . .”

“I _did_ that,” she complained, “but there was no _water_ in it!”

My masterpiece of mischief happened at the fraternity. One morning I woke up very early, about five o’clock, and couldn’t go back to sleep, so I went downstairs from the sleeping rooms and discovered some signs hanging on strings which said things like “DOOR! DOOR! WHO STOLE THE DOOR?” I saw that someone had taken a door off its hinges, and in its place they hung a sign that said, “PLEASE CLOSE THE DOOR!”–the sign that used to be on the door that was missing.

I immediately figured out what the idea was. In that room a guy named Pete Bernays and a couple of other guys liked to work very hard, and always wanted it quiet. If you wandered into their room looking for something, or to ask them how they did problem such and such, when you would leave you would always hear these guys scream, “Please close the door!”

Somebody had gotten tired of this, no doubt, and had taken the door off. Now this room, it so happened, had two doors, the way it was built, so I got an idea: I took the other door off its hinges, carried it downstairs, and hid it in the basement behind the oil tank. Then I quietly went back upstairs and went to bed.

Later in the morning I made believe I woke up and came downstairs a little late. The other guys were milling around, and Pete and his friends were all upset: The doors to their room were missing, and they had to study, blah, blah, blah, blah. I was coming down the stairs and they said, “Feynman! Did you take the doors?”

“Oh, yeah!” I said. “I took the door. You can see the scratches on my knuckles here, that I got when my hands scraped against the wall as I was carrying it down into the basement.”

They weren’t satisfied with my answer; in fact, they didn’t believe me.

The guys who took the first door had left so many clues–the handwriting on the signs, for instance–that they were soon found out. My idea was that when it was found out who stole the first door, everybody would think they also stole the other door. It worked perfectly: The guys who took the first door were pummeled and tortured and worked on by everybody, until finally, with much pain and difficulty, they convinced their tormentors that they had only taken one door, unbelievable as it might be.

I listened to all this, and I was happy.

The other door stayed missing for a whole week, and it became more and more important to the guys who were trying to study in that room that the other door be found.

Finally, in order to solve the problem, the president of the fraternity says at the dinner table, “We have to solve this problem of the other door. I haven’t been able to solve the problem myself, so I would like suggestions from the rest of you as to how to straighten this out, because Pete and the others are trying to study.”

Somebody makes a suggestion, then someone else.

After a little while, I get up and make a suggestion. “All right,” I say in a sarcastic voice, “whoever you are who stole the door, we know you’re wonderful. You’re so _clever_! We can’t figure out _who_ you are, so you must be some sort of super-genius. You don’t have to tell us who you are; all we want to know is where the door is. So if you will leave a note somewhere, telling us where the door is, we will honor you and admit _forever_ that you are a super-marvel, that you are so _smart_ that you could take the other door without our being able to figure out who you are. But for God’s sake, just leave the note somewhere, and we will be forever grateful to you for it.”