- 1. The study of symbolic representation, esp. of the origin and meaning of Scripture types; also transf. symbolic significance, representation, or treatment; symbolism.
- 2. The study of or a discourse on printing types or printing.
- 3. The study of classes with common characteristics; classification, esp. of human products, behavior, characteristics, etc., according to type; the comparative analysis of structural or other characteristics; a classification or analysis of this kind.
The concept of personality type refers to the psychological classification of different types of individuals. Personality types can be distinguished from personality traits, which come in different levels or degrees. Types involve qualitative differences between people, whereas traits involve quantitative differences. According to type theories, for example, introverts and extraverts are two fundamentally different categories of people. According to trait theories, introversion and extraversion are part of a continuous dimension, with many people in the middle. While typologies of all sorts have existed throughout time the most influential idea of psychological types originated in the theoretical work of Carl Jung, published as Psychological Types in 1921. Other typologies such as Enneagram, Socionics, Keirsey Temperament Sorter, and Myers-Briggs Indicator all have roots in Jungian philosophy.
The term "type" has not been used consistently in psychology and has become the source of some confusion. Furthermore, because personality test scores usually fall on a bell curve rather than in distinct categories, personality type theories have received considerable criticism among psychometric researchers. One study that directly compared a "type" instrument (the MBTI) to a "trait" instrument (the NEO PI) found that the trait measure was a better predictor of personality disorders. Because of these problems, personality type theories have fallen out of favor in psychology. Most researchers now believe that it is impossible to explain the diversity of human personality with a small number of discrete types. They recommend trait models instead, such as the five factor model.
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