The chief way in which innovation changes our lives is by enabling people to work for each other. As I have argued before, the main theme of human history is that we become steadily more specialized in what we produce, and steadily more diversified in what we consume: we move away from precarious self-sufficiency to safer mutual interdependence. By concentrating on serving other people’s needs for forty hours a week – which we call a job – you can spend the other seventy-two hours (not counting fifty-six hours in bed) drawing upon the services provided to you by other people.
