“Surely You’re Joking, Mr. Feynman”: Adventures of a Curious Character

“Don’t come through here! Don’t come through here!”

The colonel had sent a note around to everyone in the plant which said, “During his last visit, was Mr. Feynman at any time in your office, near your office, or walking through your office?” Some people answered yes; others said no. The ones who said yes got another note: “Please change the combination of your safe.”

That was his solution: I was the danger. So they all had to change their combinations on account of me. It’s a pain in the neck to change a combination and remember the new one, so they were all mad at me and didn’t want me to come near them: they might have to change their combination once again. Of course, their filing cabinets were still left open while they were working!

A library at Los Alamos held all of the documents we had ever worked on: It was a solid, concrete room with a big, beautiful door which had a metal wheel that turns—like a safe-deposit vault. During the war I had tried to look at it closely. I knew the girl who was the librarian, and I begged her to let me play with it a little bit. I was fascinated by it: it was the biggest lock I ever saw! I discovered that I could never use my method of picking off the last two numbers to get in. In fact, while turning the knob while the door was open, I made the lock close, so it was sticking out, and they couldn’t close the door again until the girl came and opened the lock again. That was the end of my fiddling around with that lock. I didn’t have time to figure out how it worked; it was much beyond my capacity.

During the summer after the war I had some documents to write and work to finish up, so I went back to Los Alamos from Cornell, where I had taught during the year. In the middle of my work I had to refer to a document that I had written before but couldn’t remember, and it was down in the library.

I went down to get the document, and there was a soldier walking back and forth, with a gun. It was a Saturday, and after the war the library was closed on Saturdays.

Then I remembered what a good friend of mine, Frederic de Hoffman, had done. He was in the Declassification Section. After the war the army was thinking of declassifying some documents, and he had to go back and forth to the library so much—look at this document, look at that document, check this, check that—that he was going nuts! So he had a copy of every document—all the secrets to the atomic bomb—in nine filing cabinets in his office.

I went down to his office, and the lights were on. It looked as if whoever was there—perhaps his secretary—had just stepped out for a few minutes, so I waited. While I was waiting I started to fiddle around with the combination wheel on one of the filing cabinets. (By the way, I didn’t have the last two numbers for de Hoffman’s safes; they were put in after the war, after I had left.)

I started to play with one of the combination wheels and began to think about the safecracker books. I thought to myself, “I’ve never been much impressed by the tricks described in those books, so I’ve never tried them, but let’s see if we can open de Hoffman’s safe by following the book.”

First trick, the secretary: she’s afraid she’s going to forget the combination, so she writes it down somewhere. I started to look in some of the places mentioned in the book. The desk drawer was locked, but it was an ordinary lock like Leo Lavatelli taught me how to open—ping! I look along the edge: nothing.

Then I looked through the secretary’s papers. I found a sheet of paper that all the secretaries had, with the Greek letters carefully made—so they could recognize them in mathematical formulas—and named. And there, carelessly written along the top of the paper, was pi = 3.14159. Now, that’s six digits, and why does a secretary have to know the numerical value of pi? It was obvious; there was no other reason!

I went over to the filing cabinets and tried the first one: 31-41-59. It didn’t open. Then I tried 59-41-31. That didn’t work either. Then 95-14-13. Backwards, forwards, upside down, turn it this way, turn it that— nothing!

I closed the desk drawer and started to walk out the door, when I thought of the safecracker books again: Next, try the psychology method. I said to myself, “Freddy de Hoffman is just the kind of guy to use a mathematical constant for a safe combination.”

I went back to the first filing cabinet and tried 27-18-28—CLICK! It opened! (The mathematical constant second in importance to pi is the base of natural logarithms, e:2.71828 …) There were nine filing cabinets, and I had opened the first one, but the document I wanted was in another one—they were in alphabetical order by author. I tried the second filing cabinet: 27-18-28—CLICK! It opened with the same combination. I thought, “This is wonderful! I’ve opened the secrets to the atomic bomb, but if I’m ever going to tell this story, I’ve got to make sure that all the combinations are really the same!” Some of the filing cabinets were in the next room, so I tried 27-18-28 on one of them, and it opened. Now I’d opened three safes—all the same.

I thought to myself, “Now I could write a safecracker book that would beat every one, because at the beginning I would tell how I opened safes whose contents were bigger and more valuable than what any safecracker anywhere had opened—except for a life, of course—but compared to the furs or the gold bullion, I have them all beat: I opened the safes which contained all the secrets to the atomic bomb: the schedules for the production of the plutonium, the purification procedures, how much material is needed, how the bomb works, how the neutrons are generated, what the design is, the dimensions—the entire information that was known at Los Alamos: the whole shmeer! ”

I went back to the second filing cabinet and took out the document I wanted. Then I took a red grease pencil and a piece of yellow paper that was lying around in the office and wrote, “I borrowed document no. LA4312—Feynman the safecracker.” I put the note on top of the papers in the filing cabinet and closed it.

Then I went to the first one I had opened and wrote another note: “This one was no harder to open than the other one-Wise Guy” and shut the cabinet.

Then in the other cabinet, in the other room, I wrote, “When the combinations are all the same, one is no harder to open than another—Same Guy” and I shut that one. I went back to my office and wrote my report.

That evening I went to the cafeteria and ate supper. There was Freddy de Hoffman. He said he was going over to his office to work, so just for fun I went with him.

He started to work, and soon he went into the other room to open one of the filing cabinets in there— something I hadn’t counted on—and he happened to open the filing cabinet I had put the third note in, first. He opened the drawer, and he saw this foreign object in there—this bright yellow paper with something scrawled on it in bright red crayon.

I had read in books that when somebody is afraid, his face gets sallow, but I had never seen it before. Well, it’s absolutely true. His face turned a gray, yellow green—it was really frightening to see. He picked up the paper, and his hand was shaking. “L-l-look at this!” he said, trembling.

The note said, “When the combinations are all the same, one is no harder to open than another—Same Guy.”

“What does it mean?” I said.

“All the c-c-combinations of my safes are the s-s-same!” he stammered.

“That ain’t such a good idea.”

“I-I know that n-now!” he said, completely shaken.

Another effect of the blood draining from the face must be that the brain doesn’t work right. “He signed who it was! He signed who it was!” he said.

“What?” (I hadn’t put my name on that one.)

“Yes,” he said, “it’s the same guy who’s been trying to get into Building Omega!”

All during the war, and even after, there were these perpetual rumors: “Somebody’s been trying to get into Building Omega!” You see, during the war they were doing experiments for the bomb in which they wanted to get enough material together for the chain reaction to just get started. They would drop one piece of material through another, and when it went through, the reaction would start and they’d measure how many neutrons they got. The piece would fall through so fast that nothing should build up and explode. Enough of a reaction would begin, however, so they could tell that things were really starting correctly, that the rates were right, and everything was going according to prediction—a very dangerous experiment!

Naturally, they were not doing this experiment in the middle of Los Alamos, but off several miles, in a canyon several mesas over, all isolated. This Building Omega had its own fence around it with guard towers. In the middle of the night when everything’s quiet, some rabbit comes out of the brush and smashes against the fence