From The New York Review of Books:
How do single people find partners in our fluid, urban world? One way, used by millions, is to sign up for one of the many matchmaking sites on the Internet (eHarmony.com, Match .com, Chemistry.com, JDate, Spark, and dozens of others). With many of them, you take a test, list your requirements, describe yourself, and of course pay. While some rely on your basic demographic data like age and whereabouts, others give you a personality test, and the questionnaires designed to match you up with other people are the work of such consultants as Dr. Helen Fisher, a research professor of anthropology at Rutgers, author of self-help books, including Why Him? Why Her?, aimed at helping people understand their own basic personalities and predict the types of people they’ll get along with.
Her analyses of academic studies and nearly 40,000 responses on Chemistry .com to a questionnaire she reprints in this book have led Fisher to propose a set of four fundamental personality types she calls Explorer, Builder, Director, and Negotiator, distinctions that resemble those in many other morphological systems we’ve all heard of: introverts and extroverts; Types A and B; the Humors—still used in homeo-pathy—Sanguine, Bilious, Lymphatic, and Nervous; endo-, ecto-, and mesomorphs; the classic Air, Earth, Fire, and Water; Ayurveda; the Chinese 5 Elements; the zodiac; and many others reaching back to the mists of time, referring to body types, psychological tendencies, character, or fate. The most influential modern personality inventories usually rely on a well-established one, the MBTI, developed to help with personnel placement during World War II, by Katherine Cook Briggs and Isabel Briggs Myers, who in turn relied on C.G. Jung’s typological system of introverted or (Jung’s spelling) “extraverted” thinking, feeling, sensing, and intuiting personalities.2 Fisher relies on them too—as do many modern personnel departments, and even the Pentagon.