Why do groups of even well-educated individuals sometimes persistently believe in political myths and ideologies? We follow cognition psychology in its finding that individuals sometimes stick with intuitive but false propositions. We maintain, however, that they challenge their intuition when the consequences for their individual welfare are sufficiently severe. We embed the underlying evidence in a model of social interaction that determines the conditions of a myth equilibrium, in which almost all individuals deeply believe in a certain myth and stick with its ex-post rationalization, or those of a truth equilibrium in which all individuals pursue ex-ante reasoning that aims to get as close to the truth as possible. We show how myths are clustered around certain groups and why groups are more likely to stick with political myths than individuals, which challenges the generality of Condorcet’s jury theorem.

为什么即使是受过良好教育的个人群体有时也会坚持相信政治神话和意识形态？我们遵循认知心理学的发现，即个人有时会坚持直觉但错误的命题。然而，我们坚持认为，当对他们个人福利的后果足够严重时，他们会挑战自己的直觉。我们将潜在的证据嵌入到确定神话均衡条件的社会互动模型中，其中几乎所有个人都深信某个神话并坚持其事后合理化，或那些真理均衡在这种情况下，所有个人都追求事前推理，旨在尽可能接近真相。我们展示了神话是如何围绕某些群体聚集的，以及为什么群体比个人更有可能坚持政治神话，这对孔多塞陪审团定理的普遍性提出了挑战。