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 safe-cracker." 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 and makes a noise. The guard shoots. The
lieutenant in charge comes around. What's the guard going to say -- that it
was only a rabbit? No. "Somebody's been trying to get into Building Omega
and I scared him off!"
So de Hoffman was pale and shaking, and he didn't realize there was a
flaw in his logic: it was not clear that the same guy who'd been trying to
get into Building Omega was the same guy who was standing next to him. He
asked me what to do. "Well, see if any documents are missing." "It looks all
right," he said. "I don't see any missing." I tried to steer him to the
filing cabinet I took my document out of. "Well, uh, if all the combinations
are the same, perhaps he's taken something from another drawer."
"Right!" he said, and he went back into his office and opened the first
filing cabinet and found the second note I wrote: "This one was no harder
than the other one -- Wise Guy."
By that time it didn't make any difference whether it was "Same Guy" or
"Wise Guy": It was completely clear to him that it was the guy who was
trying to get into Building Omega. So to convince him to open the filing
cabinet with my first note in it was particularly difficult, and I don't
remember how I talked him into it.
He started to open it, so I began to walk down the hall, because I was
a little bit afraid that when he found out who did it to him, I was going to
get my throat cut!
Sure enough, he came running down the hall after me, but instead of
being angry, he practically put his arms around me because he was so
completely relieved that this terrible burden of the atomic secrets being
stolen was only me doing mischief.