Myers-Briggs Astrology

Astrology is a set of systems used for attempting to better understand the past and present and for predicting the future based on the idea that there’s a relationship between the position of stars and planets in the sky and events in the life of a person. A system of astrology can be as basic as the newspaper horoscope, which categorizes all people into 1 of 12 categories. Across most of human history, astrology was widely considered a scholarly discipline. It was accepted as scientific fact in government and academia from early civilization up to at least the 17th century.

The Myers–Briggs Type Indicator (MBTI) is a psychometric assessment based on a simple questionnaire derived from the idea that there are 4 and only 4 principal psychological functions by which people experience the world. The intent is to measure and predict how individuals perceive the world and make decisions, categorizing all people into 1 of 16 categories. The Myers-Briggs is used by 89 of the Fortune 100 companies and is very popular in businesses around the world; however, it has been criticized as having methodological weaknesses, poor statistical validity, and low reliability.

The Myers–Briggs assessment is no better than astrology, and potentially much worse.

Due to their wide use, appealing results, and seeming rigorousness, Myers–Briggs tests and their results are often seen as valuable for introspection. The problem is that they have little grounding in theory or practice. They have no better correlation to reality or introspective or predictive capability than astrology. Both start with overly simplistic and flawed assumptions about how the universe and our brains work.

A Little History

The test itself was developed by Katharine Cook Briggs and her daughter Isabel Briggs Myers, neither of whom had a professional background or academic training in psychology. That fact in and of itself shouldn’t invalidate the test, but it should raise our level of skepticism. They built the test based on Carl Jung’s book Psychological Types. Carl Jung wasn’t a psychiatrist; he was a psychoanalyst, a practice Karl Popper branded as a paradigm example of an unempirical pseudoscience driven by anecdotes and conjecture rather than rigorous testing.

Pseudoscience and Cold Reading

Astrology has not demonstrated its effectiveness in controlled studies and has no scientific validity. It’s commonly regarded as pseudoscience. However, when practiced, many consider the “readings” or findings and predictions of astrology to be valid. This is often a result of confirmation bias. Confirmation bias is the tendency to search for, interpret, favor, and recall information in a way that confirms a belief or matches already observable patterns.

This human tendency to accept what seems to fit and mentally filter what doesn’t to the point of not even being aware it exists is at the heart of what makes cold reading work. Cold reading is a set of techniques used by mentalists and self-described “psychics” to imply the reader knows much more about the person than the reader actually does. One technique of cold reading is what’s called “shotgunning,” where the cold reader fires off a series of small but broad observations.

When someone is presented with a shotgun’s worth of “findings” that come from what appears to be a sort of systematized methodology, the natural human tendency is to mentally filter the fuzzy data that doesn’t fit and over-inflate the relevance or validity of the fuzzy data that does fit. Combine that with the logical fallacy of appeal to authority, and you’ve got a winning combination to fool the masses. This is exactly what astrology did and what the MBTI does.

No Confirmation

A researcher at the University of Indiana tried to rigorously verify the MBTI in comparison to common psychological methods. He wrote the following:

In summary, it appears that the MBTI does not conform to many of the basic standards expected of psychological tests. Many very specific predictions about the MBTI have not been confirmed or have been proved wrong. There is no obvious evidence that there are 16 unique categories in which all people can be placed. There is no evidence that scores generated by the MBTI reflect the stable and unchanging personality traits that are claimed to be measured. Finally, there is no evidence that the MBTI measures anything of value.

And yet, we persist in using the MBTI.

It’s Personal Now

On a personal level, it really bothers me the level of devotion to and blind faith in the MBTI. Human beings are not simple creatures. We can’t be grouped into one of a small number of categories and then labeled as having the predefined properties of that category. My greatest objection to the MBTI is its reliance on binary outcomes. For each question answered, you are either an introvert or you’re an extrovert. (Except that you can change from being an introvert to an extrovert and back again many times between MBTI assessments.) In reality, people are usually somewhere on a multi-dimensional scale of introversion and extroversion; that is to say, it’s not a 2-dimentional scale. It’s far more complex than that.

An article in The Guardian summed this up well, I thought:

The most obvious flaw is that the MBTI seems to rely exclusively on binary choices. For example, in the category of extrovert versus introvert, you’re either one or the other; there is no middle ground.

Even if you could expand on and improve the MBTI (which you can’t, because it’s copyrighted) such that instead of a binary representation across the 4 groups you could be on a multi-dimensional scale, the MBTI still gives a ridiculously limited and simplified view of human personality. We just aren’t governed entirely or even necessarily to a majority by these 4 aspects only. Human psychology is very complex; it’s difficult to pin down and study.

Why Worse than Astrology?

Astrology provides essentially random results that have no basis in reality. Some might look at this and say, “Well, yes, it’s random; but if it helps you learn something about yourself through the process, what’s the harm?” Even considering that perspective, it’s still a waste of time and energy. A distraction.

If the MBTI provides meaningless data, isn’t it only just as bad as astrology, not worse? No, it’s worse.

The problem is that the MBTI is not considered meaningless. It’s seen as the bees knees. It’s seen as science, as predictive and meaningful. It also costs money. Consequently, folks administering the MBTI have a non-trivial bias toward its being considered valid. Therefore, when it’s wrong, you can’t argue against it.

Even worse, the MBTI is being used not just for “self-reflection” and self-analysis; it’s being used for real decision-making. Some HR departments are using MBTI results for jobs placements. That’s downright scary.

The Myers-Briggs Religion

The article in The Guardian has a particularly chilling quote:

When I was back in school…a lot of teachers gave the test at the beginning of the year… In one class I was asked to write about “what I learned about myself” by taking the test. I wrote a whole paper about how unscientific the test was and how I didn’t learn anything. That teacher had me removed from her class within a week for unrelated trumped up reasons. It was like I was questioning her religion.

I have personally experienced this. When you point out how a finding isn’t correct, you usually get replies like, “Well, maybe this was true when you took the test but isn’t anymore,” or “Well, perhaps this is something you really are and just don’t know it.” These are classic cold reading gimmicks.


I’ve made up my mind that I will calmly, rationally, lovingly, and yet firmly reject any and all MBTI or MBTI-like tests when offered to or imposed upon me. I figure it’s easier to politely refuse to take an assessment than to try to convince someone a particular “finding” is wrong afterward.

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