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The Cultural Evolution of Oaths, Ordeals, and Lie Detectors

Abstract : In many cultures oaths, ordeals, or lie detectors adjudicate in trials, even though they do not discern liars from truth-tellers. I suggest that these practices owe their cultural success to cognitive mechanisms that make them culturally attractive. Informal oaths trigger mechanisms of commitment in communication. Judicial oaths, by invoking supernatural punishments, trigger intuitions of immanent justice, linking misfortunes following an oath with perjury. These intuitions justify the infliction of costs on oath takers in a way that appears morally justified. Ordeals reflect the same logic. Intuitions about immanent justice link a worse outcome following the ordeal with a guilty verdict. This link justifies the application of the ordeal, and the fixed costs involved (burning, poisoning). Lie detectors also rely on the creation of a link between a specified outcome and a guilty verdict. However, they rely on a variety of intuitions ranging from the plausibly universal to the culturally idiosyncratic.
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Contributor : Charlotte Bultel <>
Submitted on : Thursday, December 17, 2020 - 8:04:30 PM
Last modification on : Friday, July 2, 2021 - 9:58:02 AM
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The cultural evolution of oath...
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Hugo Mercier. The Cultural Evolution of Oaths, Ordeals, and Lie Detectors. Journal of Cognition and Culture, Brill Academic Publishers, 2020, 20 (3-4), pp.159-187. ⟨10.1163/15685373-12340080⟩. ⟨ijn_03080736⟩



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