We tend to think of the Myers-Briggs Type Indicator as a frivolous internet distraction, akin to the hundreds of BuzzFeed quizzes that help us pass the time and think about ourselves in new (if not especially serious) ways. But in the mid-20th century, businesses used it as a powerful tool in hiring and management, changing the trajectories of many workers’ lives. What most of these businesses’ executives didn’t know was just how arbitrary the “science” behind the indicator was.

The Myers-Briggs Type Indicator was the brainchild of a mother and daughter, Katharine Briggs and Isabel Briggs Myers. They had no formal background in psychology or statistics, but they did have a fervent belief that their experiences as mothers and wives had taught them all about the innate, immutable power of personality types. Born in 1875, Katharine Briggs had always been fascinated by the idea of personality. She became a minor celebrity in the 1920s while writing parenting columns about how she educated her daughter, Isabel. When Isabel left for college, Katharine fell into a deep depression. It was then that she discovered the writings of Carl Jung, whom she called her “savior,” her “maker,” the “author of her life.” Over time, Katharine developed a way of categorizing people’s personalities using a variation of Jung’s theory of psychological types: introversion/extraversion, intuition/sensing, feeling/thinking, and to this she added perception/judging.

Her system never really caught on until her daughter, Isabel Briggs Myers, developed it into a 117-question marketable “indicator” — never a “test,” since there were no right or wrong answers, no good or bad types. Myers sold it to Edward N. Hay, a family friend and one of the first personnel consultants in the United States. With the rise of the labor force during and after World War II, newly established consultancies like Hay’s were warming to the idea of using cheap, standardized tests to fit workers to the jobs that were “right for them,” a match made under the watchful eyes of executives eager to keep both profits and morale high.

Personality tests spoke for more than just an individual person or company; they represented an emergent culture of white-collar work.

From the end of World War II to the beginning of the arms race in the early 1950s, news of the Myers-Briggs Type Indicator thundered through Pennsylvania, New York, and Washington, D.C. As men built bomb shelters and children practiced attack drills, Isabel picked up accounts, and these accounts began to double, even triple, in size. She took on large orders from colleges, government bureaus, and pharmaceutical companies; from Swarthmore, her alma mater; from her father’s longtime employer, the National Bureau of Standards; from the First National Bank of Boston, Bell Telephone, and the Roane-Anderson Company — a subcontractor for atomic weapons her father introduced Isabel to through his contacts on the Manhattan Project. She was not shy about asking for help or using her family’s connections.

Never one to miss out on an opportunity for self-promotion, Edward N. Hay wrote to his corporate client list on Isabel’s behalf, taking the credit for the indicator’s success despite his apparent lack of familiarity with its origins or the theory behind it. “The test is based on Jung’s Psychological Type-Mind,” he informed one client. “It was developed by Mrs. Isabel Briggs-Myers out of an experiment she did with me in 1942. I have used it in my consulting work quite a little.”

By the mid-1950s, Isabel’s clients were the largest utilities and insurance companies in the United States. They regularly spent upwards of $50 a year on test booklets and answer sheets. The Home Life Insurance Company of New York purchased it twice—first to determine whether an applicant would make for a successful life insurance salesman, and then to calculate whether a life insurance applicant should pay a larger premium on his insurance. (According to Isabel’s summary of her results, extraverted intuitive types — ENTPs and ENFPs — were more likely to exhibit risk-taking behavior.) General Electric asked Isabel to type their highest-ranking executives to develop a theory about the contributions of a man’s type to his managerial success. “Under all the shifting problems that cross an executive’s desk lie three basic necessities,” Isabel wrote:

  1. He must decide.
  2. He must be right.
  3. He must convince certain key people of his rightness.

Deciding came easiest to the Js, the judging types, but since deciding was just one component of executive success, only 50 percent of the General Electric executives Isabel tested were Js. The others were Ps, the perceptive types, who were better at considering other people’s viewpoints: “more inclined to stop, look, and listen,” Isabel wrote. The introverted thinker (ISTP or INTP) was more likely to “arrive at the profoundest decisions,” while the extraverted feeler (ESFJ or ENFJ) was more likely to convince others that he was right through open and tactful communication. “His proposals thus get a fuller and more favorable hearing than do those of the thinker who sets forth his own views calmly and dispassionately but without reference to the other fellow’s and then is surprised at the opposition he encounters,” Isabel observed.

She decided that there was no such thing as the perfect executive type. “No type is naturally endowed with everything that would be useful for the necessary decision, the necessary analysis, and the necessary communication,” Isabel announced to her client. Instead, the different types of executives had different strengths. Her job now was to help them overcome their weaknesses — what she called their “inferior type functions.”

It seemed only natural that Isabel should expand her business from testing to counseling — after all, what good was the point of knowing one’s type if one did not use this knowledge for any real profit? She prescribed General Electric’s executives personality drills. The feeling types had to do logic exercises, inserting hard facts and dollar figures into their office memoranda. The thinking types had to write out “formulas” for criticism, prefacing their harsh remarks with “little chunks of sympathy or appreciation.” Isabel asked the executives to note the differences between the following (a) and (b) statements:

a. “I think you’re all wrong about Jones — ”

b. “I see why you feel that way, but I think you’re probably wrong about Jones.”

a. “Of course Bates lost the position. He should never have — ”

b. “Tough on Bates to lose the position. He should never have — ”

a. “That coat doesn’t fit across the shoulders.”

b. “That’s a becoming color on you. Too bad it doesn’t fit across the shoulders. Spoils the effect.”

“Nine times out of 10,” Isabel advised the executives, “the thinker… does think it’s tough on Bates to lose the position, even though he brought it entirely on himself. He does think the coat is a becoming color, though he can’t condone the fit. He could just as well mention these mitigating circumstances. But he does not think it worth the trouble.” Yet from the standpoint of good human relations — and overtasked human relations departments — it was worth the trouble. It prevented people from fighting executives on minor and major “points of difference”; it made subordinates feel respected and appreciated even when they were being reprimanded or, in the case of the hypothetical Bates, dismissed from their jobs. And it gave the executive a profound sense of self-satisfaction. “His own too-little-used feeling will be happier too,” Isabel concluded.

Isabel’s strongest conceptual ally was a client Hay introduced her to, named Oliver Arthur Ohmann, assistant to the vice president of the Standard Oil company and head of its industrial relations department. Ohmann was also one of the first management theorists to formulate the now-ubiquitous idea of “work-life balance,” although this meant something very different to him than what it does today. What Ohmann saw when he cast his eyes upon Standard Oil’s managers and workers, and upon the working class in general, was the spiritual impoverishment of the human psyche. “Our economy has been abundantly productive, our standard of living is at an all-time peak, and yet we are a tense, frustrated, and insecure people full of hostilities and anxieties,” he lamented in the Harvard Business Review.

The problem was not “the division of spoils as organized labor would have us believe,” Ohmann assured his readers, lest they think he was sympathetic to union leaders or socialists. Rather, it was something rotten in the idea of what it meant to work, something that affected everyone from the highest executive to the lowest oil rigger. “Is our industrial discontent not the expression of hunger for a work life that has meaning in terms of higher and more enduring spiritual values?” he asked. “How can we preserve the wholeness of personality if we are expected to worship God on Sundays and holidays and mammon on Mondays through Fridays?” The conflict between work and life was not a simple matter of time allocation. It required preserving one’s spiritual and psychological integrity across the domains of labor and leisure, the workplace and the home. It required keeping one’s personality intact.

Ohmann was on a quest to find a new religion to address the old capitalist problem of alienated labor: the estrangement of the worker’s psyche from the act of production. It was a quest he undertook not because he felt it was right in any moral or ethical sense, but because, as an executive, he felt he had no other choice if his company was to thrive. The Myers-Briggs Type Indicator, which Ohmann purchased from Hay in 1949, offered him the perfect solution for preserving the “wholeness of personality” — a way of introducing people to their true selves and convincing them that the work they were doing was a natural extension of how God had created them. The fact that it might also help enhance productivity seemed, to Ohmann, the ideal marriage of “higher and more enduring spiritual values” to the material realities of work. In its primordial form, the idea of “work-life balance” was a bargain struck between God and mammon; a bargain brokered by the Myers-Briggs Type Indicator, Ohmann informed Hay and Isabel.

Evidence mattered less than the ability to justify the divisions that already existed in a world where wealthier, whiter, and more upwardly mobile men were decreed more self-aware than everyone else.

Despite the prescience of Ohmann’s vision, Isabel did not share his sense of charity when it came to type’s spiritual reach. The benefits of knowing one’s type did not accrue to all workers equally. If a corporation employed mainly unskilled laborers, she dissuaded the company from spending too much money evaluating their workers. “The type differences show principally in the more intelligent and highly developed half of the population,” she explained to Hay. From Isabel’s experience, executives revealed “an extraordinarily high degree of type development by every criterion we have… They outstrip every group we have analyzed except some top research scientists from the National Bureau of Standards” — the government organization where Isabel’s father and son worked. By contrast, manufacturers, mechanics, and other blue-collar workers demonstrated the weakest type development, their personalities stranded in the no-man’s-land between the indicator’s dichotomies.

Of course, there existed no controlled study, and thus no real evidence, to validate Isabel’s belief in the inverse relationship between intelligence and the strength of one’s type preferences. But as was the case for the most famous test of the 1940s, the intelligence quotient (IQ) test, evidence mattered less than the indicator’s ability to justify as “natural” or “normal” the divisions that already existed in the world; a world where wealthier, whiter, and more upwardly mobile men were decreed more self-aware than everyone else. It did not occur to anyone, even Isabel, as unusual that the strongest preferences were always expressed by successful, self-assured men with ready access to power. Often it was these men who paid her to manage the personnel dilemmas they found unsavory or tedious. Hiring, firing, promotion, and attrition were all easier to talk about when employers were shielded from the lives of their employees by the abstract, pseudoscientific language of type.

Every so often, a bank or hospital would ask Isabel to evaluate their female workers — typists, nurses — to determine the relationship between personality type and a woman’s “excellence” on the job. But the answer keys had been designed with men in mind, and Isabel found she had to tinker with the answer sheets to account for her belief that women were naturally less inclined to thinking than men. Eventually, she designed two separate answer sheets: one for men and one for women. Still, the theory Isable thought she knew so well sometimes caught her off guard. The best nurses, she was surprised to learn, were introverts; the correlation between introversion and the hospital’s assessment of job performance was perfect, which she found strange but did not dwell on. The best typists were intuitive and not sensing types, even though taking dictation had everything to do with sound and sight, with hands-on experience. Isabel assumed the problem was the nurses, the typists: They had not answered honestly, she thought.

These were not the only suspicious results she encountered. Sometimes subjects whom she tested and retested seemed to change type overnight. Thinkers became feelers, judgers became perceivers. The technical term for it was “enantiodromia,” Isabel learned from a rereading of Jung, a “going over to the opposite,” in which one of the preferences a person did not express ascended to a “much more honored place” in the psyche. Her inability to validate the indicator — to show that it produced consistent results for test subjects over time — had a basis in Jungian psychology, Isabel assured Hay. It was consistent with the theory behind the type indicator.

She illustrated it to him with the following example. An unnamed woman, a secretary to whom Isabel had administered the indicator, had demonstrated a strong preference for intuition (N) and thinking (T) the first time she had taken it. But the second time, she was revealed to be a sensing (S) and feeling (F) type — a violation of the indicator’s assumption that type never changed. Either she had faked her original results, Isabel speculated, or just learning the language of type had prompted her to undergo a dramatic, possibly violent psychological conversion. Isabel decided to interview the woman to determine which it was. She showed up to her doorstep late one Sunday night, pulled out a three-by-five-inch index card, and asked her to share any dreams she may have had as of late. Isabel waited for the woman to speak, and suddenly, as if she had entered a trance, there was, Isabel reported to Hay, a sudden uprush from her subject’s unconscious of “a great many symbols and metaphors.”

She told Isabel that she had had a strange dream the previous night. She had purchased a run-down house to renovate and, while standing outside of it, had encountered a “colored woman to whom one could talk to exactly as equals.” “Members of the dark and inferior race are standard symbols for the suppressed and considered-inferior parts of one’s own psyche,” Isabel explained to Hay. The fact that the woman in the dream could be treated as an equal despite the color of her skin seemed to Isabel a sign: The test subject was ready to treat the inferior parts of her psyche (her sensing and feeling functions) as equal to its superior parts (its intuitive and thinking functions).

The analysis of her subject’s dream gave Isabel some pause. She was not bothered by the racist premises of her allegory. Rather, she knew she had to find a way to reconcile the woman’s inconsistency with her indicator. She was hopeful, Isabel told Hay, that this act of crossing over meant that the indicator did more than passively reflect the true self; it provoked the emergence of a better self from within the mind’s cocoon of uncertainty and self-hatred, preserving modes of perception (like sensing) and judgement (like feeling) that society had debased as undesirable — inefficient, weak, feminine. “The revelation, the discovery, is a discovery of value in the undervalued, in the part of her psyche which she and others have undervalued,” Isabel concluded.

Could the woman have falsified her type? Could she have cheated on a test with no right or wrong answers? In his 1956 book, The Organization Man, sociologist William H. Whyte provided his readers with a handy appendix titled “How to Cheat on Personality Tests,” which encourages test takers to do just that. Its tone is ruthless, pragmatic, and deeply funny, provided one shares Whyte’s belief that the more a test insists that it is “for the individual” — that it promotes objective self-discovery, that it “encourages difference, not conformity” — the more it masks the “total integration of the individual” within the organization’s social ethos. “The tests, essentially, are loyalty tests, or rather tests of potential loyalty,” Whyte argues. “Neither in the questions nor in the evaluation of them are the tests neutral; they are loaded with values, organization values, and the result is a set of yardsticks that reward the conformist, the pedestrian, the unimaginative — at the expense of the exceptional individual without whom no society, organization or otherwise, can flourish.”

The trick, then, was not to answer naturally or to be yourself, as the instructions for the Myers-Briggs Type Indicator encouraged. Rather, Whyte advised his reader to forge a test-taking persona. The character you created was to be a hybrid of your “own true self,” the values of the test maker (so far as you could discern them), and the values of the company.

To feel that you are ideally suited to do your job means to do it well and, more important, to do it willingly.

Despite the obvious incentives to cheat, Isabel never doubted that people were telling the truth when she administered the indicator to them, even when they knew their employers would make promotion and firing decisions based on their type preferences; even when their types changed after they had dodged the executioner’s axe. Nor did she ever entertain the idea that the values enshrined in the indicator’s questions were anything but her values, as she had inherited them from Carl Jung. The test spoke in Isabel’s voice. She did not boast of its objectivity or its empiricism, but of its capacity to prompt easy, intimate, and useful revelations about the self. “The point of it is that they are such simple everyday unthreatening, unloaded questions,” she wrote. “They are much easier to answer than soul searching ones would be and they are not important in themselves. They get answered one way by people at one end of the preference spectrum and another way by the others.”

But personality tests spoke for more than just an individual person or company; they represented an emergent culture of white-collar work. Isabel’s language of type helped give rise to a new spirit of capitalism: one in which the worker would be matched to the job that was divinely right for him. The job that would permit him to do his best and most creative work, afford him the greatest sense of personal satisfaction, endear him to his bosses and colleagues, and thus encourage him to lodge his sense of self ever deeper into his nine-to-five occupation.

The spirit endures today. “The MBTI will put your personality to work!” promises a career-assessment flier from Arizona State University, a promise that is echoed by thousands of leadership guides, self-help books, and job listings; the promise that underwrites some of our most darkly futuristic novels and films, where people are tested, sorted, and put to work according to mass assessments of their innate gifts. To feel that you are ideally suited to do your job means to do it well and, more important, to do it willingly — to bind yourself to it freely and gladly. This is the beauty of the indicator: It convinces everyone that they are exactly where they are meant to be, doing what they are meant to do.

From the book The Personality Brokers by Merve Emre. Copyright © 2018 by Merve Emre. To be published by Doubleday, an imprint of the Knopf Doubleday Publishing Group, a division of Penguin Random House, LLC.