...If our destiny is to be freed from toil by robot helpers, what are we supposed to do with our days?

To begin to tackle that existential question, I decided to invite along a scholar of work to the Automate trade show. And that's how my guest, Burton J. Bledstein, an expert on the history of professionalism and the growth of the modern middle class, got into an argument with the head of a robotics company.

It happened at the booth for Adept Technology Inc., which makes a robot designed to roam the halls of hospitals and other facilities making deliveries. The latest model­—a foot-tall rolling platform that can be customized for a variety of tasks­—wandered around the booth, resembling something out of a Star Wars film except that it occasionally blasted techno music from its speakers. Bledstein was immediately wary of the contraption. The professor, who holds an emeritus position at the University of Illinois at Chicago, explained that he has an artificial hip and didn't want the robot to accidentally knock him down. He needn't have worried, though; the robot is designed to sense nearby objects and keep a safe distance....