Everyone must have had at least one personal experience with a computer error by this time. Bank balances are suddenly reported to have jumped from 379 into the millions, appeals for charitable contributions are mailed over and over to people with crazy-sounding names at your address, department stores send the wrong bills, utility companies write that they"re turning everything off, that sort of thing. (46) If you manage to get in touch with someone and complain, you then get instantaneously typed, guilty letters from the same computer, saying, "Our computer was in error, and an adjustment is being made in your account." These are supposed to be the sheerest, blindest accidents. Mistakes are not believed to be part of the normal behavior of a good machine. If things go wrong, it must be a personal, human error, the result of fingering, tampering, a button getting stuck, someone hitting the wrong key. The computer, at its normal best, is infallible. I wonder whether this can be true. (47) After all, the whole point of computers is that they represent an extension of the human brain, vastly improved upon but nonetheless human, superhuman maybe. (48) A good computer can think clearly and quickly enough to beat you at chess, and some of them have even been programmed to write obscure verse. They can do anything "we can do, and more besides. It is not yet known whether a computer has its own consciousness, and it would be hard to find out about this. (49) When you walk into one of those great halls now built for the huge machines, and stand listening, it is easy to imagine that the faint, distant noises are the sound of thinking. And the turning of the spools gives them the look of wild creatures rolling their eyes in the effort to concentrate, choking with information. But real thinking, and dreaming, are other matters. On the other hand, the evidences of something like an unconscious, equivalent to ours, are all around, in every mail. (50) As extensions of the human brain, they have been constructed with the same property of error, spontaneous, uncontrolled, and rich in possibilities. Mistakes are at the very base of human thought, embedded there, feeding the structure like root nodules. If we were not pro vided with the art of being wrong, we could never get anything useful done. We think our way along by choosing between right and wrong alternatives, and the wrong choices have to be made as frequently as the right ones. We get along in life this way. We are built to make mistakes, coded for error.