LEFT TO RIGHT
by Isaac Asimov

Robert L. Forward, a physicist of Hughes Research Laboratories at Malibu, and a science fiction writer, demonstrated some mechanism.
“As you see,” he said, “we have here a large ring, or doughnut, of particles compressed by a magnetic field. The particles are moving at 0.95 times the speed of light' and, if I am correct, can change any object that passes through the hole of the doughnut.”
“You mean left and right will interchange?” I said.
“Something will interchange. I’m not sure what.”
“Why not try it out?” I said.
“I did that. Nothing happens. The doughnut is not powerful enough. If I can show this change, I can get a grant and make a stronger machine.”
“Do you have something in mind as a test?”
“Absolutely,” said Bob. “I’m going to pass though the doughnut hole myself.”
“You can’t do that, Bob,” I said in alarm. “You might kill yourself.”
“I can’t ask anyone else to take the chance. It’s my machine.”
“But even if it succeeds, the top of your heart will be pointed to the right; your liver will be on the left. You will no longer be able to eat.”
“Nonsense,” said Bob. “I’ll just pass through it a second time and then I’ll be exactly as I was before.”
He climbed a small ladder and jumped through.
“How do you feel?” I asked nervously.
“I’m alive,” he said.
“Yes, but how do you feel?”
“Perfectly normal,” said Bob, “I feel exactly as I did before I jumped through.”
“Well, of course you would, but where is your heart?”
Bob placed his hand on his chest, felt around, and then shook his head. “The heartbeat is on the left side, as usual. Nothing happened. There goes all my chance at a grant.”
I said hopefully, “Perhaps there is some other change.” “No. Nothing changed. Nothing at all. I’m as sure of that as I’m sure that my name is Robert L. Backward.”

SCHOOL JOKES