Sometimes you stumble upon a book that sets you on a whole new path. For Israeli historian and philosopher Yuval Norah Harari — author of "Sapiens," "Homo Deus," and "21 Lessons for the 21st Century" — it wasn’t a novel, a memoir, or even a history book that changed his world. It was a book about chimpanzees.

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Chimpanzee Politics: Power and Sex among Apes

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Interview: What Comes After Homo Sapiens?—Interview: Control The Data, Control The World