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Isaac Asimov Found! Computer-Two, like the other three that chased each other's tails in orbit round the Earth, was much larger than it had to be. It might have been one-tenth its diameter and still contained all the volume it needed to store the accumulated and accumulating data to control all space flight. They needed the extra space, however, so that Joe and I could get inside, if we had to. And we had to. Computer-Two was perfectly capable of taking care of itself. Ordinarily, that is. It was redundant. It worked everything out three times in parallel and all three programs had to mesh perfectly; all three answers had to match. -If they did not, the answer was delayed for nano-seconds while Computer-Two checked itself, found the mal-functioning part and replaced it. There was no sure way in which ordinary people would know how many times it caught itself. Perhaps never. Perhaps twice a day. Only Computer-Central could measure the time-delay induced by error and only...