Tanoshinde kudasai — Click. Grrr. Brrp. “Enjoy — Your — Meal.” It is no good replying: “I shall do my best.” The waitress wears a pink waistcoat and bow- tie. Her arms are pulleys. She recites the chef's recommendations mechanically. And this is not surprising, for she is mechanical.

She is the “multi-function concierge robot”, and the star of this year's Tokyo International Robot exhibition, which shows off the clicking edge of the new season's robotics. There may be advantages in robot waiters. They might not insist on screwing pepper over your dish, unless programmed to do so, or refilling your glass when it is only half-empty. If every table were provided with a waiter-zapper, he could not avoid catching your eye. But things could go sukiyaki wrong when the robots are being broken in, as with Mickey Mouse, playing the Sorcerer's Apprentice in Fantasia. And there will be problems of etiquette over how to complain that the sake is corked, and how much to tip a robot at the end of the meal. Other virtual humans on the horizon are a robotic dental patient, who winces and shrieks in pain, and has an inappropriateness sensor in case the trainee driller and scaler touches her plastic breast. Lady Bird cleans lavatories, and engages in “light and simple” conversation with any humans she meets on her rounds.

One day, perhaps, the robots will take over, as the slaves eventually ran the Roman Empire. But until then it makes sense to start them at the bottom of the working scale, as lavatory cleaners and in providing excuses for dodgy political loans.