ION, reason sucks.
Reason Seen More as Weapon Than Path to Truth
For centuries thinkers have assumed that the uniquely human capacity for reasoning has existed to let people reach beyond mere perception and reflex in the search for truth. Rationality allowed a solitary thinker to blaze a path to philosophical, moral and scientific enlightenment.
Now some researchers are suggesting that reason evolved for a completely different purpose: to win arguments. Rationality, by this yardstick (and irrationality too, but we’ll get to that) is nothing more or less than a servant of the hard-wired compulsion to triumph in the debating arena. According to this view, bias, lack of logic and other supposed flaws that pollute the stream of reason are instead social adaptations that enable one group to persuade (and defeat) another. Certitude works, however sharply it may depart from the truth.
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“Reasoning doesn’t have this function of helping us to get better beliefs and make better decisions,” said Hugo Mercier, who is a co-author of the journal article, with Dan Sperber. “It was a purely social phenomenon. It evolved to help us convince others and to be careful when others try to convince us.” Truth and accuracy were beside the point.
Indeed, Mr. Sperber, a member of the Jean-Nicod research institute in Paris, first developed a version of the theory in 2000 to explain why evolution did not make the manifold flaws in reasoning go the way of the prehensile tail and the four-legged stride. Looking at a large body of psychological research, Mr. Sperber wanted to figure out why people persisted in picking out evidence that supported their views and ignored the rest — what is known as confirmation bias — leading them to hold on to a belief doggedly in the face of overwhelming contrary evidence.