Language enabled early man to develop social tolerance.
Wrangham has written a summary of the thesis set out in his new book. He argues that mankind exhibits high proactive or premeditated aggressive instincts but low reactive aggressive instincts. This distinguishes us from, eg, chimpanzees, wolves and lions. They each exhibit high aggression on both counts. The possession of low reactive aggressive instincts means that we are tolerant of our fellow beings’ behaviour when it rubs us up the wrong way. We do not automatically fly off the handle. That, therefore, promotes a smoother society. But how did we get this way? Wrangham argues that the development of language enabled a tribe’s subordinates, the beta males, to conspire and kill off the bullying alpha males. Over time, then, mankind domesticated itself by selecting against tyrants and despots. So, gradually, the gene pool featured more and more people, chiefly males, with low reactive aggressive instincts.
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