The Myers-Briggs Program, similar to the Keirsey Temperament Sorter, uses the Jungian viewpoint to describe personalities in basically four different ways. The Myers-Briggs Test is strictly administered by qualified individuals.

The four types correlate with the four suits of the Tarot deck and the four elements in astrology. Fire is intuitive; water is feeling; earth is sensate; air is thinking. All four of these types can be either introverted or extroverted.

Quoting from the official Myers-Briggs website, Center for Applications of Psycological types,

"Isabel Briggs Myers, with a bachelor's degree in political science and no academic affiliation, was responsible for the creation of what has become the most widely used and highly respected personality inventory of all time. The Myers-Briggs Type Indicator® (MBTI®) instrument, now taken by at least two million people each year -- and translated into sixteen languages -- was developed over a period of more than forty years, progressing from Isabel Myers' dining room to a cottage industry, to the prestigious Educational Testing Service, and to its current publisher, CPP, Inc."

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