填空题

The three biggest lies in America are: (1) "The check is in the mail." (2) "Of course I’ll respect you in the morning." (3) "It was a computer error."
Of these three little white lies, the worst of the lot by far is the third. It’s the only one that can never be true. Today, if a bank statement cheats you out of $900 that way, you know what the clerk is sure to say: "It was a computer error." Nonsense. The computer is reporting nothing more than what the clerk typed into it.
The most irritating case of all is when the computerized cash register in the grocery store shows that an item costs more than it actually does. If the innocent buyer points out the mistake, the checker, bagger, and manager all come together and offer the familiar explanation: "It was a computer error."
It wasn’t, of course. That high-tech cash register is really nothing more than an electric eye. The eye reads the Universal Product Code--that ribbon of black and white lines in a comer of the package--and then checks the code against a price list stored in memory. If the price list is right, you’ll be charged accurately.
Grocery stores update the price list each day--that is, somebody sits at a keyboard and types in the prices. If the price they type in is too high, there are only two explanations: carelessness or dishonesty. But somehow "a computer error" is supposed to excuse everything.
One reason we let people hide behind a computer is the common misperception that huge, modem computers are "electric Brains" with artificial intelligence. At some point there might be a machine with intelligence, but none exists today. The smartest computer on Earth right now is no more "intelligent" than your average screwdriver. At this point in the development of computers, the only thing any machine can do is what a human has instructed it to do. The reason why a computerized cash register in the grocery store shows that an item costs more than it actually does is that ______.