hortly before the dreadful crash of Germanwings Flight 9525, I happened to be reading part of “The Second Machine Age,” a book by two academics at M.I.T., Erik Brynjolfsson and Andrew McAfee, about the coming automation of many professions previously thought of as impervious to technological change, such as those of drivers, doctors, market researchers, and soldiers. With the advances being made in robotics, data analysis, and artificial intelligence, Brynjolfsson and McAfee argue, we are on the cusp of a third industrial revolution.