Watson, the I.B.M.-built computer that won a game of “Jeopardy” last week over two human opponents, does not come within a million miles of replicating the achievements of everyday human thought. Watson’s builders know this; when they are interviewed they are careful to stay away from claims that their creation simulates human mental processes (although they also murmur something about future hopes). But those in charge of the artificial intelligence hype are not so careful and they delight in exciting us and frightening us with the fiction of a machine that can think. It’s great theater, or in Watson’s case, great television, but that’s all it is.