Not Human Enough; As Japan's robot experiment shows, creating a lifelike android is beyond the reach of science.

Byline: Brad Stone

If she were anything other than a robot, Saya, the receptionist at the Science University of Tokyo, would have a strong lawsuit against her employers. On a hot summer day recently, engineering students peered into her lifeless skull while her blouse was wide open, revealing--strangely enough for a robot--a brassiere. You can't argue that Saya got her job because of her people skills. She knows only a few hundred phrases. Ask her where to find a certain employee and Saya reads the office numbers straight off the Internet.

Robots like Saya are everywhere in Japan. They greet visitors at corporate offices, lure prospective students on university-recruiting weekends and wave their arms to guide traffic around construction sites. The Japanese are obsessed with attempts to create robots in man's image. But it turns out that emulating simple human behaviors is exceptionally hard for machines. As Japan's great robot experiment shows, creating a believable android is still well beyond the reach of today's scientists.

Creating a conversational humanoid is so difficult, says Saya's creator, Hiroshi Kobayashi, a professor at Science University, that researchers have to constrain the possible range of dialogue. Only then, he says, "can you actually have a scenario where ...