Inside Story

Not my type

What explains the curious persistence of the Myers–Briggs personality test?

Nick Haslam Books 8 October 2018 2141 words

From single-mindedness to pragmatism: Katharine Briggs and her daughter Isabel.

Standing at the end of a line, pressed up against the glass wall of a well-appointed meeting room, I asked myself the rueful question that all personality psychologists have posed at least once: why is the Myers–Briggs Type Indicator so damned popular? The smart, charismatic consultant facilitating this leadership course had given the questionnaire to his class and instructed us to line up according to our scores on extraversion–introversion. Far to my right on this spectrum of perkiness stood a colleague with a double-espresso personality; down this end, with no one to my left, I was decidedly decaf.

Let me get off my chest what’s wrong with the Myers–Briggs, or MBTI as it is known in the acronymphomaniac world of personality testing. The MBTI classifies people according to four binary distinctions: whether they are extraverts or introverts, intuitive or sensing types, thinkers or feelers, and judges or perceivers. Three of these distinctions rest on an archaic theory of personality typing proposed by Carl Jung, and the fourth was invented and grafted on by the test’s developers.

The four distinctions bear little relation to what decades of systematic research have taught us about the structure of personality. They are smeared unevenly over four of the five dimensions that most contemporary personality psychologists accept as fundamental, and completely ignore a fifth, which is associated with the tendency to experience negative emotions. The same effort to erase the dark side of personality is evident in the MBTI’s use of sanitising labels to obscure the negative aspects of its four distinctions. In large measure, being a thinking type amounts to being interpersonally disagreeable, and being a perceiving type to being impulsive and lacking in persistence. But in MBTI-world, all personality types are sunnily positive, a catalogue of our “differing gifts.”

The MBTI doesn’t only misrepresent the content of personality. It also gets the nature of personality fundamentally wrong. Despite masses of scientific evidence that human personality is not composed of types, its four distinctions are understood as crisp dichotomies that combine to yield sixteen discrete personality “types,” each with a four-letter acronym such as INTJ or ESFP. In reality, personality varies by degrees along a set of continuous dimensions, just like height, weight or blood pressure. In the face of mountains of research demonstrating that personality is malleable throughout the lifespan, proponents of the MBTI also argue that one’s type is inborn and unchanging. In short, the MBTI presents personality as a fixed essence whereas the science of personality shows it to be a continuous flux.

The MBTI also fails to meet the standard statistical requirements of psychological tests. Its items employ a problematic forced-choice format that requires people to decide which of two statements describes them better. Its scales lack coherence. The typology lacks re-test reliability, which means that people are commonly scored as having different types when they complete the measure on two separate occasions. Evidence that MBTI type correlates with real-world behaviour — known as predictive validity in the trade — is scant.

So why is a test with weak psychometric credentials, based on a musty theory of personality that gets the structure of human personality wrong, so enduringly popular? Arguably its weaknesses from a scientific standpoint are precisely what give it its appeal. Personality may not really form discrete types, but people relish the clarity of noun categories and binary oppositions. Personality may not really come in sixteen flavours, but MBTI types are sweet simplifications. Personality may be mutable, but people find reassurance in the idea that they have an unchanging true self. And the average person could not give two hoots about the statistical considerations that trouble test developers.

What matters to most people, at least those who complete the MBTI as an exercise in self-understanding rather than a compulsory workplace activity, is whether it offers accessible and palatable insight. And the MBTI undoubtedly provides that in spades. Its four-letter codes are readily grasped, its descriptions flatter our strengths, and the fact that its four distinctions bear some relationship to fundamental personality traits ensures that it offers a certain truthiness.

Although the shortcomings of the MBTI have been discussed within academic psychology for decades, a historical analysis has been lacking. Merve Emre’s fascinating new book, What’s Your Type? The Strange History of Myers–Briggs and the Birth of Personality Testing, fills that gap stylishly. Emre, a literature academic at Oxford, documents the genesis of the MBTI in the Jungian enthusiasms of Katharine Briggs and the more worldly ambitions of her daughter, Isabel Briggs Myers. Despite the subtitle’s questionable reference to the “birth” of personality testing — the first test dates back almost another thirty years to the first world war — the book’s recounting of the origins of the instrument is colourful and revealing.

Katharine Briggs emerges as someone single-mindedly devoted to making sense of human individuality and using that sense to guide people in directions to which she believed them suited. As a young mother without training in psychology, she developed a system of personality typing that she used in an informal child guidance, or “baby training,” enterprise, later finding a resonance between her ideas and those expressed in Carl Jung’s Psychological Types, which was published in 1921. Jung became Katharine’s “personal God”: at one point she wrote a hymn to him (“Upward, upward, from primal scum / Individuation / Is our destination / Hoch, Heil, Hail to Dr Jung!”). Encouraged by her correspondence with the great man, and armed with 3ʺ x 5ʺ index cards, Katharine refined her classification system and compulsively typed everyone she encountered, from neighbourhood children to Adolf Hitler.

Katharine’s daughter Isabel Briggs Myers had a more pragmatic cast of mind but inherited her mother’s absorption in types. After writing two mystery novels, she developed an early version of the MBTI while working for America’s first corporate personality consultant in 1943. Soon after, she launched it as a small commercial proposition. In the late 1950s the questionnaire was picked up by the Educational Testing Service, an eminent test developer and publisher in Princeton, New Jersey, giving it a chance at mainstream success and respectability. After endless wrangling between Isabel and staff psychometricians, though, the ETS lost interest and cut its losses. Seeing the instrument as “little better than a horoscope,” ETS staff insisted on conducting the same validation research as any other test would undergo, but Isabel remained resistant and possessive. Eventually a new publisher released the MBTI as a self-scored test and it quickly became a staple of the US$2 billion personality assessment industry, especially beloved by personnel consultants.

As history goes, Emre’s book is compelling and well paced. It presents Katharine and Isabel as rounded characters and places them in a richly drawn cultural and historical context. But as an account of personality testing more generally, the book is flawed. Despite having chronicled the many ways in which the MBTI was a cuckoo in the nest of personality psychology — the product of obsessed amateurs, disparaged by the psychometric orthodoxy at the ETS, popularised rather than professionalised — Emre sees it as emblematic. An emblem it is not. Unlike most other major tests, its use is not restricted to trained professionals and its legacy is protected by an almost cultish organisation that forbade Emre access to most of the Briggs–Myers papers, despite their officially being open to the public. Unlike other tests, the MBTI doesn’t promote itself by appeal to a validating body of scientific evidence. To treat the MBTI as representative of contemporary personality testing is like presenting the primal scream as representative of modern psychotherapy.

Emre is on more solid ground when she describes the functions of workforce personality testing, using the MBTI as an example. Its key purpose in that domain — only one of several in which it is used, it must be said — is indeed to select people who are likely to perform better than others in particular lines of work. Ideally that rationale is backed by evidence that the tests are valid predictors of workplace performance. Whether this purpose is benign or sinister is open to debate. It can be viewed positively as the legitimate application of behavioural science to enhance the wellbeing of workers and the success of organisations, or negatively as a dystopian tool for creating human cogs for the corporate machine.

Emre favours the darker interpretation, writing that personality typing “conscripts people into bureaucratic hierarchies.” This charge is hyperbolic: even if one is critical of the use of the MBTI or other testing, it does not force people into any position against their will, it is not employed exclusively in bureaucratic organisations, and it is used at least as much to differentiate people horizontally according to their strengths as it is to stratify them in hierarchies. The very same charge could be made against any other approach to selecting or assigning people to organisational roles, including interviews, hiring quotas or old boy networks.

The key question has to be whether personality testing selects and assigns people to work roles in ways that are better or worse than its alternatives: whether it is fairer and more valid, efficient or desirable than some other preferred metric. Unless there are grounds for believing that personality tests are worse than these alternatives, to criticise them for conscripting people into bureaucratic hierarchies is merely to express hostility to bureaucratic hierarchies.

Emre also struggles to form a consistent view when she discusses personality testing’s relationship to individuality. At times she presents the MBTI as a tool that promotes individualism by claiming to clarify each person’s specialised strengths and aid in their quest for self-discovery. At others she describes it in over-heated terms as “liquidating” or “annihilating” the self, as if a questionnaire had the capacity to destroy the person’s uniqueness. Here she cites the work of German social theorist Theodor Adorno, fierce critic of commodification (and jazz), who proclaimed that personality tests undermine human individuality.

Emre never quite resolves these antithetical views, but the paradox is only apparent. Receiving a score on a personality test, or even being assigned to an MBTI “type” does not submerge individuality. It simply provides it with a partial description that other people may share. Being described as brunette, overweight, liberal or a typical Taurus does not undermine a person’s selfhood but merely qualifies it, and the same is true when someone is described as being an ENTP. MBTI types, for all their conceptual failings, don’t reduce personal identity to one of sixteen psychological clones. They simply offer people a language for capturing some aspects of their personal distinctiveness.

In passing, Adorno’s critique of the “reified consciousness” involved in personality testing has a certain irony to it. In one of his books he recalled being asked by an American colleague whether he was an extravert or an introvert, writing contemptuously that “it was as if she, as a living being, already thought according to the model of multiple-choice questionnaires.” A few years later, while conducting his influential studies of authoritarianism, Adorno proceeded to create his own multiple-choice personality questionnaire.

Another confusion arises in Emre’s discussion of personality typology. Remembering the horrors of the Holocaust, Adorno rightly condemned the practice of assigning people to categorical types. This is a legitimate criticism of the MBTI, whose proponents view personality types as discrete and unchanging facts of nature. (Emre writes that Isabel Briggs Myers was astonished to find that scores on the MBTI’s scales were distributed in a bell curve, not in the camel-humped way that type theory supposed.) Emre notes this criticism of typology but then mistakenly applies it to personality testing in general. In contrast to the MBTI, almost all personality tests are explicitly anti-typological. These tests assess differences between people along a continuum without invoking bogus categories, and they do not make ill-founded claims that their scores correspond to unchanging personal essences. By failing to recognise that typological thinking is a specific failing of the MBTI, Emre misses the extent to which major criticisms of that instrument do not tarnish personality testing as a whole.

To serious students of personality, the continuing success of the MBTI within the testing industry is a source of bafflement. Emre’s book does not diminish that dismay, but it helps to clarify why the instrument is the way it is. Despite its unpromising beginnings, she demonstrates that it has a powerful appeal, offering an intuitively attractive way to apprehend ourselves as a pattern of distinctive strengths. In Emre’s preferred Foucauldian terminology, the MBTI is an effective “technology of the self.” The fact that it is a rather Bronze Age technology is almost immaterial. •

What’s Your Type? The Strange History of Myers–Briggs and the Birth of Personality Testing
By Merve Emre | HarperCollins | $32.99 | 336 pages