The Happiness Hypothesis: Finding Modern Truth in Ancient Wisdom

by Jonathan Haidt

Studies of “motivated reasoning”13 show that people who are motivated to reach a particular conclusion are even worse reasoners than those in Kuhn’s and Perkins’s studies, but the mechanism is basically the same: a one-sided search for supporting evidence only. People who are told that they have performed poorly on a test of social intelligence think extra hard to find reasons to discount the test; people who are asked to read a study showing that one of their habits—such as drinking coffee—is unhealthy think extra hard to find flaws in the study, flaws that people who don’t drink coffee don’t notice. Over and over again, studies show that people set out on a cognitive mission to bring back reasons to support their preferred belief or action. And because we are usually successful in this mission, we end up with the illusion of objectivity. We really believe that our position is rationally and objectively justified.