The Art of Thinking Clearly

by Rolf Dobelli

Science labels this tendency the Forer effect (or the “Barnum effect”). The Forer effect explains why the pseudosciences work so well—astrology, astrotherapy, the study of handwriting, biorhythm analysis, palmistry, tarot card readings, and séances with the dead. What’s behind the Forer effect? First, the majority of statements in Forer’s passage are so general that they relate to everyone: “Sometimes you seriously doubt your actions.” Who doesn’t? Second, we tend to accept flattering statements that don’t apply to us: “You are proud of your independent thinking.” Obviously! Who sees himself or herself as a mindless follower? Third, the so-called feature-positive effect plays a part: The text contains no negative statements; it states only what we are, even though the absence of characteristics is an equally important part of a person’s makeup. Fourth, the father of all the fallacies, the confirmation bias: We accept whatever corresponds to our self-image and unconsciously filter everything else out. What remains is a coherent portrait.