See Samo’s essay series here for the definition of “intellectual legitimacy” as it’s being used in the OP:
An idea has intellectual legitimacy insofar as it is recognized by society as respectable and reasonable. An intellectually legitimate idea does not need to be recognized as credible by all people, or even by very many people at all. There only needs to be a general perception that society at large holds the idea to be legitimate. Powerful institutions and individuals are seen as tolerating or endorsing it. Such a perception isn’t necessarily coupled to whether an idea is true.
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individuals routinely use legitimacy as a shortcut for evaluating the quality of the ideas around them. What may intuitively feel like evaluating an idea on its merits has oftentimes already factored in how an idea is communicated, and who is communicating it. We do this because it is harder for us to assess claims in fields that are outside our areas of expertise and so, instead, we learn from experience which sources to rely on. Evaluating an idea’s intellectual legitimacy is often safer and easier than evaluating the idea itself, and in a healthy society, the shortcut works. This makes the shortcut an efficient and effective heuristic for individuals. Even then, though, an intellectually valid idea that is correctly perceived as legitimate might ultimately still turn out to be false.
See Samo’s essay series here for the definition of “intellectual legitimacy” as it’s being used in the OP:
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