About ten years ago—a point at which some stage of an advanced technological future already seemed to have arrived—I sat with a friend at the People’s Republik, a bar in Cambridge, Mass., looking around the room and noting how nothing really looked too different than it would have in the 1970s or the 1990s, aside from the faint glow of phone screens illuminating some people’s faces, and maybe the stronger glow of Big Buck Hunter in the corner.