MBTI, or the Myers-Briggs Type Indicator, is probably the most popular personality test. It contains four axes: Introverted/Extraverted, iNtuitive/Sensing, Thinking/Feeling, Judging/Perceiving. If you take the test, you may be assigned one of 16 personality types, for instance I would be INTJ.
The MBTI is regarded as pseudoscience, perpetuated by the popular consciousness and HR departments rather than academic research. One time I asked a personality psychologist and she said it was just so far off from reality that nobody even bothered talking about it. Psychologists prefer to talk about another personality model, called the Five Factor Model, also known as The Big Five. This has five axes, labeled Openness, Conscientiousness, Extraversion, Agreeableness, and Neuroticism (OCEAN).
I’ve often remarked that although the Five Factor Model is supposedly more scientific, it’s clearly a lot less compelling. And isn’t that something? I couldn’t honestly say that I find astrology compelling, or ear candles compelling, but the MBTI, now that’s some yummy pseudoscience. I have some remarks on what makes MBTI a pseudoscience, what makes it compelling, and what its problems are.
MBTI as pseudoscience
Caveats: I do not have a psychology background, and due to constraints on my time I do as little research as possible. This is a casual chat, and I invite readers to make corrections and fill gaps.
You can design a questionnaire with any set of questions, and calculate a score from them. You don’t need any scientific training to do it. Just call it the Hermione/McGonagall score and brand it as a “What Harry Potter Character are You?” quiz. As ridiculous as it sounds, that quiz measures something “real”, even if only how you respond to that quiz.
The question is, how do you figure out what the “best” thing to measure is, and how do you pick the “best” questions to measure it? These are difficult questions, with no good answers. But at least we can throw a bunch of math at it and pretend we solved the problem.
The Five Factor Model is based on factor analysis. My understanding is that psychologists comes up with hundreds(?) of questions relating to personality–basically everything they can think of. After giving this questionnaire to a bunch of people, they use a statistical software package to assign each respondent a mere five numbers, and these numbers are optimized to predict how each respondent answered the hundreds of questions. Afterwards, they whittle down the list of questions to get a shorter questionnaire that suffices to measure the five numbers.
Nothing about this methodology suggests that the Five Factor Model is measuring any fundamental truths about the human brain or whatever. But it at least guards against the personal biases of the researchers. Different researchers can try it, and they’ll find more or less the same thing. (It seems to me that bias may enter through the design of the initial large questionnaire, but eh??)
In contrast, the MBTI is based on a fiat assertion about how personality works. Well sure, Myers and Briggs and Jung made some observations and applied their personal insights before making fiat assertions. But there aren’t really any guard-rails against the personal biases of its creators. MBTI is measuring something real to be sure, but there isn’t a good answer to “Why measure this thing and not some other thing?” Why MBTI and not Harry Potter characters or enneagrams?
What I have come to accept, is that the MBTI doesn’t need to be scientific to be useful on some level. It doesn’t need to be designed in a way that’s robust to the personal biases of its designers. Observations and personal insights followed by fiat assertion are “good enough”. Honestly I think HR departments could squeeze value out of Harry Potter quizzes too, if they set their minds to it.
I also have to say, some of the stuff that comes out of academic psychology is hardly any better. Consider Moral Foundations Theory, which describes people’s moral concerns in terms of five foundations: care, fairness, loyalty, authority, and purity. Many years ago, this was popularized in psychologist Jonathan Haidt’s book The Righteous Mind. But what is it based on? As far as I can tell, it comes from personal observations followed by fiat assertions, no better than MBTI.
MBTI as compelling
For all the science of the Five Factor Model, and pseudoscience of MBTI, oddly enough they converge. It turns out that Sensing is correlated with Openness, Thinking with Agreeableness, Perceiving with Conscientiousness, and Extraversion with Extraversion.
But MBTI still feels far more compelling, and I think it’s all in the names of the axes. Where MBTI has flattering names for both ends of each axis, The Big Five only name one end of each axis, and either use unflattering names (neuroticism) or names that are unflattering to the other side (agreeableness, conscientiousness, openness).
Perhaps this is because the MBTI is ideologically committed to the idea that personalities are value-neutral. You’re Valid no matter where you land. Psychologists, on the other hand, have no such commitment, and will happily test the hypothesis that some personalities lead to worse outcomes.
Although, I don’t think the unflattering names are based on any sort of empirical data. The names are totally made up. Factor analysis will give you a set of axes, but doesn’t tell you what to call them. You have to look at what questions were associated with each axis, and make names up. And psychologists are not very good at coming up with names. When I blogged about the Big Five back in 2012, I dug up a table listing various names that psychologists had used for the five factors. Apparently OCEAN is just the tip of the godawful names iceberg.
Funnily enough, last I checked Wikipedia, some genius decided to give each of the spectra more flattering descriptors for both sides. I’m not sure if that comes from a researcher or a Wikipedia editor, but bless them.
- Openness to experience (inventive/curious vs. consistent/cautious)
- Conscientiousness (efficient/organized vs. easy-going/careless)
- Extraversion (outgoing/energetic vs. solitary/reserved)
- Agreeableness (friendly/compassionate vs. challenging/detached)
- Neuroticism (sensitive/nervous vs. secure/confident)
What would be fun, is coming up with axes names that make both ends sound unflattering. Leave your ideas in the comments.
Deeper problems with the MBTI
On the internet, the MBTI is mostly meme fodder, and is harmless as meme fodder goes. But that’s not the only context where it is used. The thing to understand, is that the MBTI is a commercial product sold by the Myers-Briggs Company. You can become a certified MBTI practitioner by paying $2500 (in my area) for a four-day class. And it costs even more to administer tests, produce reports, and take refresher courses.
I mean, presumably that mostly comes out of the budgets of HR departments, so I guess it’s up to you how upset you feel about money moving from the coffers of one corporation to another. Personally I don’t care that much, I’m just submitting this for the reader’s consideration.
A long time ago I knew an MBTI practitioner, and she answered a few of my questions about it. One of my concerns was that MBTI would be used to select job candidates or the like. Apparently practitioners are taught that this is unethical, and good for them. It does leave me wondering what decisions, if any, are made on the basis of MBTI, and whether those decisions could possibly be ethical. It seems like the MBTI is caught between unethical and useless.
Another concern was that MBTI is treated as a typology, when it’s obviously not. Imagine saying that there are two height-types: above average and below average. Well, I guess that’s technically correct, but a misleading way to think about it, when the mode of the distribution is pretty close to the boundary. The 16 MBTI types are like that, but more so. What I’ve heard is that MBTI practitioners are aware of the issue, and say in their defense that it’s just a common misconception. But, this is clearly a “common misconception” that they are deeply invested in promoting themselves. The Myers-Briggs website says:
The 16 personality types of the Myers-Briggs Type Indicator® instrument are listed here as they are often shown in what is called a “type table.”
And you can find self-appointed defenders saying stuff like
Psychological Type is dynamic – each of the 16 Types are psychological systems of energy
Yeah, so that’s anti-convincing.