"If you've ever studied any abstract mathematical system you'll be able to understand how the changing of one basic axiom can alter the whole structure almost beyond recognition. Suppose that change in a basic axiom were not a clean change, but that for a time both the axiom and its alternative were to be used interchangeably and unpredictably. You would have results that were double-valued. You would have contradictory results following from whatever you began with until the old axiom got weeded out entirely. "Perhaps you can see that well enough to understand everything. I hope so, Martha. If you can I can skip the landing. We DID land. We crashed, and we landed safely. We also did something else. I think that when they check the records they'll find that the _Endore_ also came back to Earth and reported that it hadn't actually landed on Metapor. It did all those things--returned over a year ago, landed safely, and was crushed in landing. If you could see HOW it could do all those things--it's like the page in a book; you pass it if you look for it, and find it if you don't look for it. "It's happening here on Earth right now and will keep on happening until the old basics that contradict the new ones are no longer operating. You see, Martha, we knew that would happen. That's why we came back. The new system is so much more perfect than the old. SHE taught it to us when we landed. Ford Gratrick and his fellow objectors were killed in the ship that crashed. They also were on the ship that came back to Earth. They're alive and they're dead." Martha's face was a mask of confusion. She was trying to understand and not knowing how. Ren saw this and tried again. "Suppose we try from this angle," he said patiently. "If a car is going ten miles an hour it will be ten miles farther on at the end of an hour. If it goes twenty miles an hour it will be twenty miles farther on. But suppose it goes both ten miles an hour and twenty miles an hour. At the end of an hour it will be ten miles and twenty miles along, and according to what the Earth is used to it would have to become two cars to do that. "If it went every speed from zero to twenty miles an hour it would have to become an infinite number of cars, and occupy every position from the starting point to a twenty-mile distance at the end of an hour. That would be the conventional conclusion to the abstract problems. With the new basics it does just that--except that it is still just one car, and yet never was just one car and never will be. It CAN'T be, because there is no such thing, in the new system, as a one thing. "I myself am not Ren Gravenard, only Ren Gravenard, or anything else that your old ideas can conceive of. You'll see, Martha. The whole world will see soon, just as I did after we had been on Metapor a short while and had gotten the contradictions out of my mind and my structure." "Then what are you?" Martha asked tensely.