Our powers of reasoning? Turns out they're not that useful - except for arguing and being a talk show blowhard. So we learn over at Jonah Lehrer's Frontal Cortex. There, Lehrer cites a study in which random folks judged the merits of five jams which earned widely differing scores from jam experts.
Without giving much thought, the random, non-experts scored the jams similarly to how the experts did.
But once the subjects were asked to fill out questionnaires about why they scored the jams the way they did, their judgments changed. That's because their thinking clouded what really matters in taste tests. "All this extra analysis seriously warped their jam judgment," Lehrer writes.
And it turns out that gladwellian decision-making applies to preference tests of all sorts of things - from jelly beans to cars and apartments.