Lunatics and crackpots don't necessarily have seriously flawed thinking. Different priors, different information, and small biases can lead to entirely different conclusions. Most people avoid crackpot status by never venturing to attempt an original thought, or any thought, really, and just going along with conventional wisdom.
Most of the canonical sources here, like Korzybski, Jaynes, and Everett, were seen as crackpots at one time, and some still are in some quarters.
"Crackpot" has been leveled as an epithet against just about every major thinker. Had the epithet existed then, Galileo surely would have qualified even by the most conservative use of the term.
I regard the term as indicating that somebody is going very far afield of established thinking. 99.9% of all crackpots will be wrong. But it may be worth listening to them anyways.
Today's post, Tolerate Tolerance was originally published on 21 March 2009. A summary (taken from the LW wiki):
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This post is part of the Rerunning the Sequences series, where we'll be going through Eliezer Yudkowsky's old posts in order so that people who are interested can (re-)read and discuss them. The previous post was Why Our Kind Can't Cooperate, and you can use the sequence_reruns tag or rss feed to follow the rest of the series.
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