“Humans rarely think for themselves. Rather, we think in groups. Just as it takes a tribe to raise a child, it also takes a tribe to invent a tool, solve a conflict or cure a disease. No individual knows everything it takes to build a cathedral, an atom bomb or an aircraft. What gave Homo sapiens an edge over all other animals and turned us into the masters of the planet was not our individual rationality, but our unparalleled ability to think together in large groups.”