Katharine Cook Briggs and her daughter Isabel, creators
of the Myers-Briggs personality test, early 1900s

“Personality is never general; it is always particular,” wrote Gordon Allport, a Harvard psychologist, in 1938. While “personality” once meant merely personhood, since the late eighteenth century it has referred to the qualities that make a person distinctive. Within the field of psychology, the term was initially used of abnormal clinical phenomena, such as the “alternating” and “double” personality William James discussed in The Principles of Psychology or the “dissociation of personality” that Morton Prince examined in his 1906 book of that name. But in the 1920s and 1930s, in part through Allport’s work, personality—including the “normal” kind—became a central concern of psychological research, with journals, textbooks, courses, and conferences devoted to the subject. In 1930 Allport remarked that interest in personality had reached “astonishing proportions,” and in 1938 he declared “the discovery of personality” to be “one of the outstanding events in psychology of the present century.” But he worried that his colleagues had become too concerned with measurement and the search for general laws, and he cautioned against the assumption that one could understand “the totality of a personality by having a series of scores.”

The first personality test in the US was the Woodworth Personal Data Sheet, which was developed during World War I as a way of identifying recruits who might be susceptible to shell shock. It consisted of 116 questions that measured neuroticism, such as, “Are you often frightened in the middle of the night?” Numerous self-report questionnaires followed. The Thurstone Personality Schedule and the Bernreuter Personality Inventory, which appeared around 1930, posed dozens of yes-or-no questions that yielded scores on several scales, including extroversion–introversion. The Minnesota Multiphasic Personality Inventory (MMPI), published in the early 1940s, consisted of 504 statements, to which test-takers were to respond “True,” “False,” or “Cannot Say”: “I loved my father”; “I have never had any black, tarry-looking bowel movements.” There were also “projective” tests, with no set answers: Hermann Rorschach’s inkblots, introduced in Switzerland in 1921 and popularized in the US in the 1930s; and the Thematic Apperception Test (TAT), developed in the 1930s by the Harvard psychologist Henry Murray and his colleague and lover Christiana Morgan, which asked the subject to tell stories about a set of ambiguous, unsettling drawings—a boy looking at a violin, a woman clutching the shoulders of a man whose face and body are averted from her.

The temptation of a series of scores was too great; several of these tests are still widely used, and are part of a multi-billion-dollar industry fraught with questionable science and questionable applications, as Annie Murphy Paul discusses in her meticulously researched 2004 book, The Cult of Personality Testing. Although the tests’ creators were thoroughly credentialed—professors at top universities and doctors at top hospitals—their projects were shaped, as Paul argues, “by the demands of industry and government.” Some tests, including the Rorschach and the MMPI, were originally intended for use with the mentally ill but were eventually given to the general population as well; others were designed for “normal” people, to measure their aptitude for combat, school, or the workplace. The Humm-Wadsworth Temperament Scale, for example, was designed in 1935 by a psychologist and the vice president of a natural-gas company to help personnel departments. It was extolled in a 1942 Reader’s Digest article as a “people-sorting instrument” that could “place the worker in the proper niche, keep him happy, and increase production.” People-sorters, which had been around since the 1910s, were sometimes used to screen out Communists and union sympathizers and to select “henpecked husbands” disposed to submit to a boss. The Reader’s Digest article presented a happier picture, of managers constructively pointing out their workers’ faults, which the workers would then graciously temper.

Isabel Briggs Myers, a housewife in Swarthmore, Pennsylvania, read this article with great interest and immediately wrote to her mother, Katharine Cook Briggs. These two women and the “Indicator” they would create are the subject of Merve Emre’s The Personality Brokers, an archivally rich mix of history, biography, and a bit of reporting. Katharine and Isabel had no formal training in psychology or psychiatry. In Emre’s telling, they simply perceived “how hungry the masses were for simple, self-affirming answers to the problem of self-knowledge.” They believed they could “craft a language of the self that was free from judgment,” and they set out to help people put their “different gifts” to appropriate uses, particularly in the workplace.

Although Isabel led the development of the Myers-Briggs Type Indicator, her mother had built its foundation through long study. Katharine was born in Michigan in 1875 to a zoologist father and a devout Christian mother, and as a student at Michigan Agricultural College she was “wrenched and shaken” by her recognition that “science may lack the data that the soul possesses.” She was concerned with the “problem of personal salvation” and came to believe that specialized labor—one line of work, pursued zealously and for the social good—would ensure redemption. After college, she married Lyman Briggs and moved to Washington, D.C., where she turned her home into a “laboratory of baby training,” instilling obedience and curiosity in Isabel, her only surviving child, and reporting on her activities in magazine articles.


When Isabel left for Swarthmore College, in 1915, the “educational experiment” that had occupied Katharine for eighteen years came to an end, and she grew anxious and depressed. She invented and patented contraptions for luggage and purses; she read works of biography and philosophy; she wrote a screenplay and short stories; finally, she spent much of her days playing solitaire. In 1923, Katharine discovered Carl Jung and, inflamed with passion—which extended to Jung himself, about whom she began writing gay erotica—she dedicated her life to thinking about “type.” “One need not be a psychologist in order to collect and identify types,” Katharine wrote in a 1926 New Republic article explaining and elaborating on Jung’s theory, “any more than one needs to be a botanist to collect and identify plants.”

In his 1921 Psychological Types, Jung proposed that people could be classified according to their basic psychological functions and attitudes. Katharine impressed Jung’s importance on Isabel, who in 1942 would draw on his “magnificent idea” and postulate sixteen possible types made up of four binaries, expressed in pairs of letters: extroversion (E) or introversion (I), intuition (N) or sensing (S), thinking (T) or feeling (F), judging (J) or perceiving (P). The Indicator was designed not to identify “problems” (traits that might cause trouble on a battlefield or a production line, for instance) but to describe psychologically unremarkable people in a neutral or positive way. From the beginning, Katharine understood the importance of equality. In 1926 she noted that “neither credit nor discredit is attached to membership in any type, since each has its failures, its mediocrities, and its successes.” The first published version of the Indicator, from 1943, offered comforting instructions: it was “not, strictly speaking, a test,” for there were “no right or wrong answers,” and whatever the results, “each type has its own special advantages.”

This nonjudgmental tone and lack of hierarchy, and the presumption of universal specialness, help account for the enduring popularity of the MBTI (as it is now known), which boasts some two million users per year. Fortune 500 companies, Silicon Valley startups, financial and consulting firms, and US government agencies routinely use it to screen applicants and to gain insight into employees, and it’s a common feature of executive training sessions and staff retreats. The Financial Times reports that McKinsey employees’ internal profile pages list their MBTI types. It’s used by religious schools to evaluate applicants, and by all kinds of career counselors. Many people choose to take it on their own, drawn in by the promise of recognition and belonging. The “minimal group paradigm” of social psychology describes how people randomly assigned to trivially defined groups (the Klee or Kandinsky types, the red shirts or the blue shirts) will often identify with and favor their own group at the expense of others. There is an international network of MBTI meetups for those who wish to congregate with their own type.

Crucial to the MBTI’s success as a tool of both self-discovery and the assessment and management of others is a conception of personality as immutable, even congenital. “Every one of us is born either an extravert or an introvert, and remains extravert and introvert to the end of his days,” Katharine wrote. But although most consumers of the test presume its powerful claims must have some kind of scientific basis, for decades the MBTI has been regarded by scientists as ill-founded. It has been criticized for its strict dichotomies—many people will be somewhere in between the two poles of a given category, and studies show that around half of users retaking the same questionnaire are assigned a different type—and for its failure to predict outcomes in such areas as job performance and team effectiveness. It has been called “an act of irresponsible armchair philosophy,” “too slick and simple, possessing an almost horoscope-like quality,” and “a party game.”

Indeed, although some defenders of the MBTI insist on its scientific validity and reliability, the ideas underlying its creation were drawn from Jung and from popular culture. The notion, embraced by Katharine and Isabel, that one’s defining qualities never evolve or fluctuate represented an evolution in such popular thinking, a departure from both the Protestant ideal of character that prevailed in the nineteenth century and the conception of personality that emerged in the early twentieth. Character, according to the earlier view, could be built: if you were not naturally endowed with a sense of rightness and civic duty, you could just read a book of character studies for emulation. Starting in the early twentieth century, according to the historian Warren Susman, this valorization of character gave way to a fascination with personality. Like character, personality could be acquired, though toward different ends. Self-help manuals in the 1910s and 1920s encouraged readers to think of themselves as somebodies, and instructed them on matters such as poise, elocution, and charm. “You can compel people to like you,” wrote the self-help guru Orison Swett Marden in Masterful Personality (1921), a prospect most famously explored in Dale Carnegie’s How to Win Friends and Influence People (1936). Although personality was thought by some to be a special property that select people had—“a certain something,” “an indescribable something,” “an indefinable quality,” or just “It”—it was generally thought to be available to anyone who put in the effort. It was less a particular collection of qualities than a blankness that invited projection and desire.


Most psychologists of the 1920s and 1930s held that everyone, by virtue of being a person, already had personality, though how individual qualities could be measured and classified was another matter. After reading the Reader’s Digest article in 1942, Isabel began working for Edward N. Hay and Associates, a Philadelphia firm that developed workplace aptitude tests. She was tasked with validating the Humm-Wadsworth Temperament Scale, which she pronounced useless. Rather than peg workers as normal or abnormal, Isabel realized, management should identify workers’ strengths and strive to make everyone feel needed, in order to boost both morale and efficiency.

She soon began devising her own test. She formulated the sixteen-type table; she drafted questions she thought would reveal a person’s nature—“Do you prefer to (a) eat to live, or (b) live to eat?”—and tried them on family and friends. In May 1943 Isabel copyrighted the Indicator, and in July she pitched it to Hay, who agreed to use and distribute it. The Indicator did not immediately find its niche in the growing personality testing industry, and it wasn’t until the mid-1970s that it became a financially successful product. Emre recounts these early struggles and triumphs in great detail, a valuable expansion of the concise history offered by Annie Murphy Paul and others.

Like her mother, Isabel had tried her hand at many things. “What are the right things for me?” she wrote to Katharine in 1918 as she looked for a job in Memphis, where her husband, Clarence “Chief” Myers, was training to be a bomber pilot. The couple soon moved to Philadelphia, where Chief would attend law school, and in 1923 Isabel moved in with her parents for a spell to save money. While there she started a “Diary of an Introvert Determined to Extravert, Write, & Have a Lot of Children,” which contained Gatsby-like to-do lists (“Two hours writing”; “Never wear anything soiled”). She had a son in 1926 and a daughter the following year, and she raised them by her mother’s paradigm of obedience and curiosity.

In 1928 she saw an announcement in New McClure’s Magazine for a mystery-novel contest and resolved to write a book by the deadline, which was five months away. Her submission, Murder Yet to Come, won the contest, earning her a cash prize of $7,500 (more than $100,000 today), serial publication, and a two-book contract. But most of her prize money went into stocks that died in the crash, and although for a few years she kept writing—including, with resignation, the second book she owed her publisher, which was panned by reviewers—by 1934 she had recommitted to the vocation of motherhood. It would be another eight years before she turned to people-sorting, which would occupy her for the rest of her life.

Isabel’s first client, Emre reveals, was the Office of Strategic Services, the forerunner to the Central Intelligence Agency. The OSS had been charged with selecting and training spies, for which it set up Station S, a secret assessment center on an estate outside Washington, D.C. Operatives were to be matched with the missions best suited to their personalities, a task that proved daunting for the center’s leader, Henry Murray, the former director of the Harvard Psychological Clinic and cocreator of the TAT, whose ideas about espionage came from novels. In 1944 Donald MacKinnon, Murray’s graduate student, purchased the Indicator and added it to the center’s intake process. After the war, he used it in a series of studies on creative people he conducted as the director of UC Berkeley’s new Institute of Personality Assessment and Research (IPAR). IPAR invited writers, painters, and architects to participate in tests, games, and therapy, and to be observed interacting with one another. (Oddly, despite devoting chapters to both Station S and IPAR, Emre does not discuss how or to what extent the Indicator was used by these institutions—though she did post on Twitter a “type table,” evidently from IPAR’s archives, classifying William Carlos Williams as an INFJ and Truman Capote as an ENFP—or whether this use lent it legitimacy.)

Emre, a scholar of postwar American culture, presents the Indicator as a naive instrument of a bullish era that promoted adjustment and conformity. In The Organization Man (1956), William H. Whyte reported that 60 percent of the American companies he had surveyed in 1954 were using personality tests (his book includes a delightful appendix: “How to Cheat on Personality Tests”). By the mid-1950s, utilities, pharmaceutical, and insurance companies were ordering large quantities of the Indicator and sometimes requesting Isabel’s help in understanding its broader implications, as General Electric did when it asked her to analyze its top executives.

In 1959 Henry Chauncey, a former Harvard dean and the founder and president of Educational Testing Services (ETS), which began publishing the Scholastic Aptitude Test (SAT) in 1943 and was now exploring mass personality testing, offered Isabel a contract, and the Indicator gained other major clients, including the Protestant Episcopal Church, Brown University, and the California State Department of Corrections. But despite Chauncey’s enthusiasm about the Indicator, his colleagues nearly all viewed it with skepticism. Trying to validate it, they discovered irregularities. A statistics Ph.D. tasked with writing a manual for the Indicator savaged it in an internal memo. The theory behind the Indicator, he wrote, was Jungian but with even “less in the meaning of the terms.” “E-I merely measured talkativeness,” and “S-N was merely conservatism versus liberalism.”

Emre, too, is critical of the MBTI, but who wouldn’t be? Its cheerful simplicity, its vague, mystical underpinnings, its coziness with business psychology, the way it endorses normality in the guise of self-acceptance—it’s an easy target. What distinguishes Emre’s book is its close, sympathetic study of the test’s creators and their aspirations. They clearly had goals aside from making money, and they never did make much; the boom happened after Isabel’s death in 1980. Katharine loftily “believed that knowing one’s type could save the soul of an individual while prompting him to assume the specialized offices that would help him advance civilization.” Emre confesses in the book’s introduction that at times she wanted it to be “a story of feminist triumph.” As scientifically unsound as type has proven to be, it’s still painful to read about Isabel’s being dismissed by the all-male ETS staff as “that horrible woman.” She and Katharine were scrappy and determined, and even when they crossed ethical lines—Katharine tried to “see [the] soul” of a teenage girl by analyzing her dreams (for which she was scolded by Jung), and Isabel persuaded the principal of her kids’ high school to give her copies of students’ permanent records and IQ tests—it’s hard not to admire their boldness.

Isabel’s father, mother, and forty-four-year-old daughter died in the span of a decade, and in 1975 she learned she had tumors throughout her body. The same year, ETS, which had continued to publish the Indicator despite its poor financial results, formally ended its contract with her. But in her last years Isabel laid the groundwork for the MBTI’s later success. She began working with Mary Hawley McCaulley, a psychologist at the University of Florida who would revive the Indicator and launch the Center for Applications of Psychological Type, where Isabel’s papers would be closely guarded (Emre was denied access to them). Isabel and Mary found a new publisher, Consulting Psychologists Press (CPP), which made the Indicator shorter and its descriptions of type “less dogmatic,” and soon introduced a self-scoring version. CPP sold the Indicator to anyone who would pay, and revenues climbed, from $10,000 in 1975 to $100,000 in 1979. (It is still published by CPP, for which it is the driving force behind roughly $20 million of annual revenue.) By the time Isabel died, in 1980, the Indicator had already achieved cult status: it was the topic of dissertations and an annual international conference; it had secured a motley global following, with, for instance, 250,000 users per year in Japan; and a book adapting Isabel’s ideas, Please Understand Me (1978), was on its way to becoming a best seller.

A major tendency in postwar clinical psychology has been to move away from binaries (normal/abnormal, extrovert/introvert, etc.) and toward ideas of a spectrum or continuum. Starting in the 1950s, researchers seeking to identify personality’s basic components kept arriving at five essential factors: openness to experience, conscientiousness, extroversion, agreeableness, and neuroticism, known since the 1980s as the “Big Five.” Big Five–based tests give users percentages or levels of each trait, rather than spitting out a four-letter epithet. But like the MBTI, these tests depend on self-reporting, so their accuracy may be undermined by subjects’ self-deception, lack of self-awareness, or varying abilities to comprehend the questions themselves and the possible intent behind them—a Keynesian beauty contest of gaming out the psychological significance of selecting one answer over another.*

Although there are tools for investigating personality that do not depend on subjects’ self-knowledge, including functional magnetic-resonance imaging (fMRI), which some researchers claim can show differences between the brains of introverts and those of extroverts (among other things), such scientific advances are not likely to threaten the MBTI and its kin, which serve a different purpose. The MBTI is wildly unempirical, but the need it answers is not fundamentally about knowledge. Like astrology (which is newly trendy and lacks the MBTI’s Boomer corporatism), or even the Hogwarts houses (which have been embraced, with levity and sincerity, by fans of the Harry Potter novels), typology need not be believed to be found useful or diverting.

The MBTI is still thriving. Enthusiasts claim that it has saved their marriages, or inspired them to find new partners or new jobs; it has taught them to accept themselves and others, even helped them connect to God (“Jesus was a classic ENTP,” Paul deadpans). They blazon their initialisms on dating and social-media profiles. Thousands of people have paid thousands of dollars to be certified to administer the MBTI. Of course, for many who encounter it, in school, at work, or on the Internet, it’s just another personality quiz: not particularly meaningful, but fun and harmless—an attitude that helps explain Cambridge Analytica’s success in deploying Big Five–based personality questionnaires to collect data about Facebook users. In the age of the tongue-in-cheek BuzzFeed quiz, answering a few questions about yourself seems like no big deal.

But placing oneself and others in categories is perilous. Hiring and promotion decisions can always be attributed to “fit,” an ominously vague term that can cloak myriad forms of bias. A 2002 study found several pervasive misconceptions among HR managers concerning the effectiveness of certain staffing practices; a majority of managers believed “there are really only four basic dimensions of personality, as captured by the Myers-Briggs Type Indicator,” and that conscientiousness was a better predictor of job performance than intelligence. Employers have been sued over their use of personality tests that ask questions about religion, sexual orientation, political beliefs, and drug use. In 1994 a security company was sued for asking applicants for security guard positions whether they thought “most companies make too much profit” and “marijuana should be legalized.” Although personality tests are not used in undergraduate admissions, personality has been an important—and nebulous—area of assessment since the advent of the “well-rounded” candidate and holistic review. The lawsuit against Harvard for discriminating against Asian-American applicants, who tended to be rated lower than others on such metrics as “positive personality” and “likability,” has renewed questions about the extent to which such decisions should take into account personal characteristics, and how those can be fairly assessed.

Gifts Differing was the title of Isabel’s book about psychological type, which she finished on her deathbed—but of course not all gifts are valued equally. The belief in unchanging fundamental personal characteristics, which is a big part of her test’s reassuring appeal, can easily reinforce a belief in natural hierarchy. The very concept of type is conservative, premised on a sense that certain things are predetermined, which can lead to control as well as to acceptance.