What's the future of work? Will gigs replace salaried employment, and will robots eventually leave humans with nothing to do? I see reason for skepticism, but also for concern.

Technology, of course, is already making independent work a lot easier. It puts workers into contact with customers and helps them run a back office. More importantly, it allows individuals to build and promote their reputations at low cost. Customers used to rely on a taxi company's reputation, or choose a washing machine by the manufacturer's brand. Now, each worker has a brand: On Uber, customers can reject drivers based on their personal ratings. A firm's collective reputation, with the concomitant control of its employees' behavior, is becoming gradually less important.

That said, technology can also favor standard salaried employment. The economists George Baker and Thomas Hubbard, for example, have noted how onboard computers could change U.S. trucking. By monitoring behavior, they would solve a moral hazard problem: Drivers have little incentive to be as careful with company trucks as they would with their own. As a result, more drivers could become employees of companies that buy and maintain fleets, rather than going it alone. They wouldn't have to invest in their own vehicles, which makes them vulnerable to recessions by putting their savings in the same sector as their labor; and they wouldn't be out of pocket and out of work when their trucks broke down.