Because it turns out we are our own favorite talk show hosts. "Everybody has a blowhard inside them," says Jonah Leher, and that blowhard is working pretty much full-time to confirm our pre-existing biases. Lehrer, whose wonderfully written insights into how we think are regularly featured by SBM Blog (and who can now be found at Wired), explains that we are not rational beings so much as we are powerful rationalizers:
So, everyone, heads way up during jury selection, eh?
Let me tell you a story about strawberry jam. In 1991, the psychologists Timothy Wilson and Jonathan Schooler decided to replicate a Consumer Reports taste test that carefully ranked forty-five different jams. Their scientific question was simple: Would random undergrads have the same preferences as the experts at the magazine? Did everybody agree on which strawberry jams tasted the best?
Wilson and Schooler took the 1st, 11th, 24th, 32nd, and 44th best tasting jams (at least according to Consumer Reports) and asked the students for their opinion. In general, the preferences of the college students closely mirrored the preferences of the experts. Both groups thought Knott’s Berry Farm and Alpha Beta were the two best-tasting brands, with Featherweight a close third. They also agreed that the worst strawberry jams were Acme and Sorrel Ridge. When Wilson and Schooler compared the preferences of the students and the Consumer Reports panelists, he found that they had a statistical correlation of .55. When it comes to judging jam, we are all natural experts. We can automatically pick out the products that provide us with the most pleasure.
But that was only the first part of the experiment. The psychologists then repeated the jam taste test with a separate group of college students, only this time they asked them to explain why they preferred one brand over another. As the undergrads tasted the jams, the students filled out written questionnaires, which forced them to analyze their first impressions, to consciously explain their impulsive preferences. All this extra analysis seriously warped their jam judgment. The students now preferred Sorrel-Ridge—the worst tasting jam according to Consumer Reports—to Knott’s Berry farm, which was the experts’ favorite jam. The correlation plummeted to .11, which means that there was virtually no relationship between the rankings of the experts and the opinions of these introspective students.