The allure of synthetic entertainment—television, the Internet—is eerily reminiscent of the false promise of industrial food. It seems like a distillation of the good aspects of a social life, always entertaining yet easy to abandon when it becomes tedious or challenging. But, like junk food, it is ultimately unsatisfying and potentially harmful. Our brains, genetically adapted to help us negotiate a successful course through complex, changing, and often hazardous natural environments, are suddenly confronted with an overload of information and stimulation independent of physical reality.