"Think of the world of work as divided between “power systems” and “control systems,” Brynjolfsson suggested. The power systems (people, forklifts, airplanes) help move things around; the control systems (plant managers, business plans, engineering diagrams) explain where it needs to move. In the nineteenth and twentieth centuries, the engines, factories, and other technologies of the industrial revolution automated and enhanced the world’s power systems. After a period of dislocation, workers successfully adapted: they took over the control systems, becoming engineers and managers. But now machines are taking over the control systems, too, and it isn’t clear what workers can do next."