Scientists recreated a Consumer Reports study in which students were asked to rate strawberry jams. The initial results mirrored the findings of the magazine’s taste experts. In the next phase of the experiment, things got stranger ..
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. What happened? Wilson and Schooler argue that “thinking too much” about strawberry jam causes us to focus on all sorts of variables that don’t actually matter. Instead of just listening to our instinctive preferences, we start searching for reasons to prefer one jam over another. For example, we might notice that the Acme brand is particularly easy to spread, and so we’ll give it a high ranking, even if we don’t actually care about the spreadability of jam. Or we might notice that Knott’s Berry Farm has a chunky texture, which seems __ like a bad thing, even if we’ve never really thought about the texture of jam before. But having a chunky texture _sounds_ like a plausible reason to dislike a jam, and so we revise our preferences to reflect this convoluted logic
from “We Are All Talk Radio Hosts,” by Jonah Lehrer, Wired.com, 5 August 2010