A history of personality types
For as long as there are records, people have sorted one another into types. Each era kept the idea and demanded better evidence for it.
Three parts of the soul
In the Republic, Plato divided the soul into reason, spirit and appetite (overview). Three-part models of mind recur through history: Kant's faculties of knowing, feeling and desiring, and the psychologist Ernest Hilgard's "trilogy of mind", cognition, affection and conation (Kihlstrom). The ICA's Thinking, Feeling and Willing faculties follow this line, as inspiration rather than evidence.
The four temperaments
Greek medicine linked health to four bodily humors. The physician Galen later tied them to four temperaments, sanguine, choleric, melancholic and phlegmatic, a scheme that lasted well over a thousand years. The humors were wrong; the habit of describing people by a few recurring temperaments was not.
Jung's psychological types
In 1921 Carl Jung published Psychological Types, describing attitudes (introversion and extraversion) and functions of thinking, feeling, sensation and intuition (overview). Katharine Cook Briggs and Isabel Briggs Myers turned his ideas into a questionnaire, the Myers-Briggs Type Indicator, whose first manual was published in 1962.
The lexical route to the Big Five
In 1936 Gordon Allport and Henry Odbert listed close to 18,000 English words that describe people (Allport and Odbert, 1936). Researchers who analyzed how such words cluster kept finding five broad factors, later summarized as the Big Five (Goldberg, 1990). Trait models describe degrees rather than types, and now have the broadest research base.
What each era got right
| Era | Idea | What lasted |
|---|---|---|
| Ancient philosophy | Three parts of mind | Thinking, feeling and will as distinct |
| Ancient medicine | Four temperaments | A few recurring patterns are recognizable |
| Early 20th century | Psychological types | Preferences in how people perceive and judge |
| Late 20th century | Traits and factors | Measurement, evidence and degrees, not boxes |
Where the ICA sits
The ICA keeps the oldest idea, recurring roles, and the newest demand, evidence. Its model names four dimensions after long-observed roles, and its research program tests them. See also cognitive style research.
Questions
Are personality types real?
People differ in consistent ways. Most evidence supports describing those differences as degrees on dimensions rather than as separate types.
Sources
Keep reading
Take the next step.
How people have typed one another, from the four temperaments and Plato's three-part soul to Jung, the MBTI and the Big Five, and what each got right.