A blunt instrument

Psychologist Marc Wilson puts the MBTI on the couch.

The Myers-Briggs Type Indicator is the Donald Trump of personality tests. It’s everywhere, makes bold claims that many find hard to stomach and, in spite of that, is obscenely successful. Researcher Adrian Furnham writes, in the Encyclopedia of Personality and Individual Differences, that the Myers-Briggs test is completed by as many as five million people every year.

It costs nearly $4000 to train as a certified MBTI instructor in New Zealand, the Myers Briggs company’s website says. If you just want an official MBTI, then I found quotes ranging from $120 to $450 from a variety of local organisations.

Is it worth it? Although widely used in career counselling and by education and business organisations, the MBTI hasn’t got the best reputation in academic circles. One criticism is that it is based on a theoretical idea of personality, namely that people tend to be extroverted (E) or introverted (I), intuitive (N) or sensing (S), thinking (T) or feeling (F), perceiving (P) or judging (J). That means you’ll fit into one of 16 boxes – your “type”. What’s more, Katharine Briggs and Isabel Briggs Myers argued that “type never changes”. But what if the theory is wrong? What if the MBTI measures something different? It’s not clear that perceiving versus judging was even part of the theory of psychotherapist Carl Jung, whose work inspired the pair to develop what’s now known as the MBTI.

The strong position on these 16 boxes is that they are discrete – once an ENTJ, always an ENTJ. But this is bollocks. Whether you’re an extrovert or an introvert, for example, is based on which side of a scale-based cut-off you fall. But people who fall close to either side of the cut-off are more like each other than people at the extremes. I’m also more extroverted in some settings than others, so the answer to, “Are you an extrovert?” is, “That depends.” At a broader level, the idea that type never changes is also a bit strong – personality does change, though usually not very quickly.

The MBTI is a tool, and like many tools it can be used well or badly. I suspect that practitioners on the ground are somewhat softer than might be suspected from author Merve Emre’s account, framing type more as a preference than a rule.

It seems to me that, like many personality “tests”, the MBTI is particularly useful as a tool for introspection. It highlights that people are different, and an awareness of this can be genuinely useful for reflecting on how to work with that diversity.