"Surely You're Joking, Mr. Feynman!" - unam.

drug called ketamine, which was used as an anesthetic. I've always been interested in
questions related to what happens when you go to sleep, or what happens when you get
conked out, so they showed me the papers that came with the medicine and gave me one
tenth of the normal dose.
I got this strange kind of feeling which I've never been able to figure out
whenever I tried to characterize what the effect was. For instance, the drug had quite an
effect on my vision; I felt I couldn't see clearly. But when I'd look hard at something, it
would be OK. It was sort of as if you didn't care to look at things; you're sloppily doing
this and that, feeling kind of woozy, but as soon as you look, and concentrate, everything
is, for a moment at least, all right. I took a book they had on organic chemistry and
looked at a table full of complicated substances, and to my surprise was able to read
them.
I did all kinds of other things, like moving my hands toward each other from a
distance to see if my fingers would touch each other, and although I had a feeling of
complete disorientation, a feeling of an inability to do practically anything, I never found
a specific thing that I couldn't do.
As I said before, the first time in the tank I didn't get any hallucinations, and the
second time I didn't get any hallucinations. But the Lillys were very interesting people; I
enjoyed them very, very much. They often gave me lunch, and so on, and after a while
we discussed things on a different level than the early stuff with the lights. I realized that
other people had found the sense­deprivation tank somewhat frightening, but to me it was
a pretty interesting invention. I wasn't afraid because I knew what it was: it was just a
tank of Epsom salts.
The third time there was a man visiting ­­ I met many interesting people there ­­
who went by the name Baba Ram Das. He was a fella from Harvard who had gone to
India and had written a popular book called Be Here Now. He related how his guru in
India told him how to have an "out­of­body experience" (words I had often seen written
on the bulletin board): Concentrate on your breath, on how it goes in and out of your nose
as you breathe.
I figured I'd try anything to get a hallucination, and went into the tank. At some
stage of the game I suddenly realized that ­­ it's hard to explain ­­ I'm an inch to one side.
In other words, where my breath is going, in and out, in and out, is not centered: My ego
is off to one side a little bit, by about an inch.
I thought: "Now where is the ego located? I know everybody thinks the seat of
thinking is in the brain, but how do they know that?" I knew already from reading things
that it wasn't so obvious to people before a lot of psychological studies were made. The
Greeks thought the seat of thinking was in the liver, for instance. I wondered, "Is it
possible that where the ego is located is learned by children looking at people putting
their hand to their head when they say, 'Let me think'? Therefore the idea that the ego is
located up there, behind the eyes, might be conventional!" I figured that if I could move
my ego an inch to one side, I could move it further. This was the beginning of my
hallucinations.
I tried and after a while I got my ego to go down through my neck into the middle
of my chest. When a drop of water came down and hit me on the shoulder, I felt it "up
there," above where "I" was. Every time a drop came I was startled a little bit, and my
ego would jump back up through the neck to the usual place. Then I would have to work