Module 4 The Need for Psychological Science

LEARNING TARGET

• 4-1 Explain how hindsight bias, overconfidence, and the tendency to perceive order in random events illustrate why science-based answers are more valid than those based on common sense.

• 4-1 How do hindsight bias, overconfidence, and the tendency to perceive order in random events illustrate why science-based answers are more valid than those based on common sense?

Some people suppose that psychology is mere common sense—documenting and dressing in jargon what people already know: “You get paid for using fancy methods to prove what my grandmother knows?” Indeed, Grandma is often right. As the baseball great Yogi Berra (1925–2015) once said, “You can observe a lot by watching.” (We have Berra to thank for other gems, such as “Nobody goes there any more—it’s too crowded,” and “If the people don’t want to come out to the ballpark, nobody’s gonna stop ’em.”) Because we’re all behavior watchers, it would be surprising if many of psychology’s findings had not been foreseen. Many people believe that love breeds happiness, for example, and they are right (we have what Module 40 calls a deep “need to belong”).

But sometimes Grandma’s common sense, informed by countless casual observations, is wrong. In many other modules, we will see how research has overturned popular ideas—that familiarity breeds contempt, that dreams predict the future, and that most of us use only 10 percent of our brain. We will also see how research has surprised us with discoveries about how the brain’s chemical messengers control our moods and memories, about other animals’ abilities, and about the effects of stress on our capacity to fight disease.

Other things seem like commonsense truth only because we so often hear them repeated. Mere repetition of statements—whether true or false—makes them easier to process and remember, and thus more true-seeming (Dechêne et al., 2010; Fazio et al., 2015). Easy to remember misconceptions (“Vitamin C prevents the common cold”) can therefore overwhelm hard truths. This power of familiar, hard-to-erase falsehoods is a lesson well known to political manipulators and kept in mind by critical thinkers.

“ Those who trust in their own wits are fools.”

Proverbs 28:26

Three roadblocks to critical thinking—hindsight bias, overconfidence, and perceiving patterns in random events—help illustrate why we cannot rely solely on common sense.