Jonah Lehrer explains how we respond to rumors:

Not only are we persuaded by false rumors that get repeated, but we're persuaded even when the false rumors get repeated by one person. As Psy Blog notes, a recent study by Kimberlee Weaver and colleagues, found that "if one person in a group repeats the same opinion three times, it has 90% of the effect of three different people in that group expressing the same opinion."

That's why one popular and persistent blogger, or one partisan hack on CNN or Fox News, can do so much damage.

A single loud voice repeating bullshit is, as far as the brain is concerned, roughly equivalent to lots of voices repeating bullshit. And if lots of voices are repeating bullshit, then the bullshit must be true.Of course, the paradox of this post is that, even though I set out to discredit the Michelle Obama rumor, I actually made things worse.

Robert George on how this is just the latest incarnation of a conservative urban legend that pops up each presidential election.

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