Why are we suckers for Astrology, the Myers-Briggs, and other shaky psychology tests?
Issue 119: Our hot take on phony personality tests and zodiacs
Scientists love to hate on the Myers-Briggs Personality Indicator Test, easily the most popular and well-known measure of personality. The test puts people into 16 categories based on four personality dimensions:
Extraversion (E) or introversion (I), which measures whether you get energy from outwardly focused action like socializing or from inwardly focused activities like quiet reflection
Intuition (N) or sensing (S), which measures how much you see big picture patterns rather than focusing on sensory information from direct experience
Thinking (T) or feeling (F), which measures whether you make decisions using logic rather than by focusing on feelings
Judging (J) or perceiving (P), which measures your preference for structure rather than spontaneity
Depending on you score across these dimensions, you get labeled and matched with famous people (most of whom are long since deceased and never completed the test). Are you an “ISFP” like Bob Dylan and Rihanna or an “ENTJ” like Bill Gates and Margaret Thatcher? Perhaps you’re an “INTP” like Albert Einstein and Tina Fey?
Yet psychologists have repeatedly argued that the Myers-Briggs has dubious predictive ability and is grounded in debunked theory. To make matters worse, it’s unreliable. Which means that if you take the test more than once to learn more about your “true self”, it’s quite likely to give you different answers each time. As Laith Al-Shawaf notes, “any psychologist will tell you, it’s mostly bullshit.”
A recent report in Scientific American compared the results of the Meyers-Briggs to other personality scores, ranging from the Big 5 to Astrological signs (see their results in the figure below). They investigated an MBTI-style test and a Big Five test to see how well each predicted 37 life outcomes (see their full report for details), ranging from how many close friends they had to how often they exercised to how satisfied they were with life. Here is what they found:
On average, the Big Five test was about twice as accurate as the MBTI-style test for predicting these life outcomes, placing the usefulness of the MBTI-style test halfway between science and astrology—literally. When we tried predicting these same life outcomes using astrological sun signs (e.g., whether someone is a Pisces or Aries), we achieved zero prediction accuracy. In other words, sun sign astrology didn’t appear to work at all for predicting people’s lives. And while the MBTI-style test fared better, it was still often wrong in its predictions. What’s more, adding MBTI-style personality results to Big Five ones didn’t lead to predictions that were any more on the mark than Big Five ones alone.
(If you’d like to compare your own Big Five and MBTI results to see how accurate they are, you can do so here using a free version of the test they created.)
Despite these lackluster results, the Myers-Briggs Type Indicator remains the most popular personality test in the world. It’s a favorite among the LinkedIn Crowd, Fortune 100 companies, and government agencies. Indeed, more than one-and-a-half million people take it each year and a full 89 out of the Fortune 100 companies were using the measure as recently as 2014. It is a thriving multimillion dollar industry.
The test is also being used to determine our love life. Yes, people actually do put their Myers-Briggs category on their Tinder profiles and funders gave 1 million dollars to develop an app that matches couples based on their Myers-Briggs personality types. The test also makes a pretty regular appearance on dating profiles and NYT Wedding announcements, like a young couple below who decided to evaluate their romantic capability:
Things were going so well that Ms. Maillian suggested they take the Myers-Briggs Type Indicator, a personality test, on their phones.
“Out of 16 different personality profiles, both of us were ESTJ-A,” said Ms. Maillian. “I couldn’t believe we are both the executive mind-set. That reinforced a compatibility.”
What is it about this scientific mess that people so readily buy into? We believe that one of the bugs that drives psychologists crazy is actually a feature that explains the test’s enduring popularity.
After you complete the Myers-Briggs test, you get sorted into one of 16 categories. Each group is often given an appealing name: the “logical pragmatist”, “compassionate facilitator”, or “insightful visionary” — providing a perfect new title for a professional development seminar or your online dating profile.
The problem is that these categories contradict how contemporary psychologists think about personality. Most experts agree that human personality can be boiled down to five or so fundamental traits—the BIG 5: extraversion, agreeableness, conscientiousness, openness to experience, and neuroticism. Each trait is a continuous dimension, so that someone can score high, low, or anywhere in between.
Unfortunately, however, it is quite hard (even if you’re a psychologist) to conceive of yourself in five-dimensional space. It’s also awkward to tell people at a conference event or cocktail party that you have a moderate score on extraversion, moderate-to-high on agreeableness and conscientiousness, high on openness, and moderate-to-low on neuroticism. This is hardly sparkling dinner party conversation!
This is why assigning people to Myers-Briggs’ categories is compelling. Scoring low on extraversion and high on openness doesn’t sound particularly impressive, but being a “mastermind” does. People would much rather claim a group identity that includes Sun Tzu, Isaac Newton, Jane Austen and Arthur Ashe (setting aside the fact that none of these people ever took the Meyers-Briggs and several were deceased hundreds of years before the test was even invented).
The use of categories is a great marketing maneuver and a big part of the reason behind the popularity of many dubious personality tests from the Myers-Briggs to the infamous TIME Harry Potter Quiz or Cosmo’s quiz to help you learn what kind of lover you are. The same logic also applies to Astrology signs! All these tests operate a bit like the Sorting Hat from Harry Potter, slotting us into different groups. People crave self-definition and social identities provide this for us. We are attracted to group memberships that provide both a sense of connection to people just like us and distinction from others—what Marilynn Brewer termed “Optimal Distinctiveness”.
The ease with which people form group identities can be traced back to one of the most important studies in social psychology (we think it might be THE most important experiment). In the minimal group experiments from the 1970s, people were randomly assigned to groups after completing a test of dubious merit, such as their ability to estimate the number of dots in an image or their preference for abstract art (e.g., Klee vs. Kandinsky).
Within minutes, they had created a new sense of identity and were treating their new in-group members very differently from out-group members. In fact, this research revealed that the mere act of being categorized as a member of a group was sufficient to cause discrimination. It also inspired on the of the most important theories in the social sciences—Social Identity Theory.
When we use personality tests that impose categories—like the Meyers Briggs or Astrology—we risk exaggerating the differences between groups and the similarities within them. When this occurs with other types of identities like race or gender, we typically call it “stereotyping” and we try to avoid it. When consultants do it in companies, they are creating the same dynamics and doing it on dubious scientific grounds.
There is reason for caution when it comes to categorizing others too readily by personality as well. We might well fail to hire, promote, or even marry someone because they fall into a false category about which we make exaggerated assumptions. Even with the Meyers-Briggs, putting people into categories is the weakest use of the test. It is roughly as useful as astrology.
This is why organizations could do much better by creating other meaningful social identities. If you can create a sense of belonging around other social identities, people might feel less of a need to rely on these dubious tests to create a sense of self.
News and Updates
Jay was interviewed in the New York Times last week to discuss political polarization. He was asked if there is any hope for fighting polarization. He said “there are solid, well-tested strategies for reducing affective polarization. These are possible on a large scale if there is sufficient political will.”
But he quickly added that these strategies “are up against all the other factors that are currently driving conflict and animosity, including divisive leaders like Donald Trump, gerrymandering, hyperpartisan media (including social media), etc. It’s like trying to bail out the Titanic.”
Simply put, it is difficult, if not impossible, to attempt to counter polarization at a time when partisan sectarianism is intense and pervasive.
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Catch up on the last one…
As the final part for our series “How to write a popular science book”, our paid subscribers were gifted our original book proposal for The Power of Us in last week’s issue! The sneak-peek is public and you are learn more about how to write a book proposal in parts 1 and 2.
How to write a popular science book (part III): A sneak peak at our original book proposal
This is Part III in our series on “how to write a popular science book proposal”. In Part I, we described how to go From an Idea to the Proposal. In Part II, we described The Auction, Writing, and Promotion aspects of the process. In Part III, we thought it might be fun to give you a sneak peak at original book proposal for
I challenge the statement that most psychologists believe it to be bullshit. MBTI is rooted in Jungian psychological functions - attitude, perception and decision making. A Freudian fan might not believe Jung’s theories to be credible but that’s a matter of preference, not necessarily fact/fiction.
As someone who has seen MBTI workshops transform from lighthearted team exercises into serious hiring criteria, this warning feels especially timely. Our desire for self-definition is natural and important but satisfying it through scientifically shaky personality buckets might be doing more harm than good in an age where algorithms are doing more research on who you than perhaps you are doing on yourself.