A more interesting question is why, in this age of Google and Snopes, does misinformation persist? As a few of the Slashdot commenters note, plenty of urban legends that have been eminently checkable on Snopes for years continue to circulate. I suspect this can at least be partially explained by an intriguing theory of how the mind works, advanced last spring by Hugo Mercier and Dan Sperber, two cognitive scientists.

There is a belief -- a myth, really -- that the human mind takes in information, and then reasons through it to produce ideas and opinions. But humans are notoriously poor at reasoning as it is conventionally understood, predictably falling into known traps, such as the confirmation bias (the tendency to absorb information that supports what one already thinks). Mercier and Sperber argued that the explanation for why human reasoning is so poor isn't because it's deficient, but because we've measured it against the wrong standard. Human reason doesn't exist to provide us with a more accurate picture of the world; it exists to structure and promote discourse, or what Mercier and Sperber term "argument." The human mind is better at spotting the flaws in someone else's argument than its own, and in groups or pairs can do much better on a variety of tests than when flying solo.



As much as we like to think otherwise, facts, at least according to this schema, aren't at the core of how we understand the world, but they sure are useful for rebutting the way other people do.



This is the reason why the Internet has brought a Golden Age of Fact Checking: The Internet is a medium perfect for rebuttals, and facts are the lifeblood of rebuttals. Snopes, for example, helps us refute a too-quickly-forwarded email, but few people would just browse Snopes to learn random things.



Mercier and Sperber's theory about how the mind works gets to the core of why we value accuracy in journalism and political communications: We use it as a proxy for credibility, because factual mistakes are the easiest targets for an argument to the contrary. Whether or not you have your facts straight is how we judge you -- as a politician, a publication, or a pundit.



But this is unfortunate, because accuracy is not always a good proxy for quality. Quality, however, is much more difficult to assess.



I have been a fact checker. I have scrutinized tens if not hundreds of thousands of words of text for misspellings and misplaced digits. Almost always, when a fact is wrong, you can correct it without so much as changing a word of the surrounding argument. What you're doing is inoculating the piece from the charge of not having the facts straight. But the piece can be just as wrongheaded once the numbers are correct. View-from-nowhere journalism or he-said-she-said reporting can be entirely accurate, but do little to help explain an issue or an idea, to say nothing of inspiring empathy or compassion.