Extraversion and introversion

The traits of extraversion (also spelled extroversion) and introversion are a central dimension in some human personality theories. The terms introversion and extraversion were introduced into psychology by Carl Jung, although both the popular understanding and current psychological usage vary. Extraversion tends to be manifested in outgoing, talkative, energetic behavior, whereas introversion is manifested in more reflective and reserved behavior. Jung defined introversion as an "attitude-type characterised by orientation in life through subjective psychic contents", and extraversion as "an attitude-type characterised by concentration of interest on the external object". Extraversion and introversion are typically viewed as a single continuum, so to be higher in one necessitates being lower in the other. Jung provides a different perspective and suggests that everyone has both an extraverted side and an introverted side, with one being more dominant than the other. Virtually all comprehensive models of personality include these concepts in various forms. Examples include the Big Five model, Jung's analytical psychology, Hans Eysenck's three-factor model, Raymond Cattell's 16 personality factors, the Minnesota Multiphasic Personality Inventory, and the Myers–Briggs Type Indicator. In September 1909, Swiss psychiatrist Carl Jung used the term introverted in a lecture at Clark University. A transcript of this lecture was then published with two others in a journal in 1910, the first time the term appeared in print. In the lecture he mentions that love that is "introverted", "is turned inward into the subject and there produces increased imaginative activity". His 1921 book Psychologische Typen was published as Personality Types in English in 1923. It described the "introverted" in detail for the first time. In his later paper, Psychologische Typologie, he gives a more concise definition of the introverted type, writing:He holds aloof from external happenings, does not join in, has a distinct dislike of society as soon as he finds himself among too many people.