The Why #18: Why do smart people believe dumb horoscopes?

By Dan Monheit 30.4.21

Question submitted by Millie, Coogee

It’s a great question Millie, and the rise of Pluto suggests that the answer is just around the corner (along with an event that will prompt you to reassess a close relationship and a major life decision that will require you to trust your gut).

Who doesn’t love a horoscope, a palm reading or an aura audit(?), especially when they tell us how close we are to financial prosperity, ever-lasting love and discovering our true purpose in this large, lonely world?

The funny thing is, the same science that proves horoscopes are bullsh*t, also explains why so many people (even really really smart ones) believe in them.

So join me, my Taurian adventurer, as we embark on a great journey, upon which enlightened and a true spiritual awakening are all but guaranteed.

Barnum Effect

The Barnum Effect describes our tendency to believe that personality descriptions are tailored specifically to us, even though they are in fact vague and could apply to virtually anybody.

In 1948 Psychologist Bertram Forer handed out a specially devised questionnaire to his students. The students were told to complete the questionnaire honestly, and were promised a personalised ‘sketch’, or description, of their personality type in return. Forer collected the completed questionnaires and returned the following week with personalised sketches for each of his students. Upon receiving their sketch, each student was asked to provide a rating, from 0 (poor) to 5 (spot on) in regard to how accurately the sketch described them.

The average accuracy rating was 4.3, which is rather incredible when you consider that each student received the exact same sketch (which Forer had assembled from a newsstand astrology book the night before). As it turns out, almost anything can apply to almost anyone.

Horoscopes, clairvoyants, and ‘which Harry Potter character are you’ tests all play into our curiosity (and vanity). Their deliberate vagueness leaves room for us to insert our own meaning and relevance, helping universal statements about being self critical, falling short of our potential or seeking security seem truly personal.

These descriptions tend to be considered even more believable when they’re positive (surprise!), and come from a perceived authority, such as a widely circulated newspaper, or a mystical woman surrounded by crystals and candles in a velvet carnival tent.

The Barnum Effect is a powerful tool for getting people to self-identify as prospective customers. Brands can use it by highlighting product truths that flatter the audience (‘running gear for people who know that ‘bad conditions’ are only ever a state of mind’) or by heroing a particular segment (‘peanut butter for dads who want the best for their kids’).

Smart marketers will know what to do from here.

Behaviourally Yours,

Dan Monheit

PS If you missed the last edition, you can still check out why groups of adults argue over who gets to pay the bill here.

Bad Decisions Podcast
Learn more about the Barnum Effect on episode 26 of the Bad Decisions podcast.

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Want more?
Check out Dan with Think With Google’s four-part series on the ‘Messy Middle’.

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