Who classified personality into introvert and extrovert types?

Concept

A personality typology groups recurring patterns of thought and behaviour into broad categories. Introversion and extraversion describe the direction in which a person mainly directs psychological energy and attention.

Introversion is oriented more toward the inner world of ideas and reflection, whereas extraversion is oriented more toward people, activity, and the external world.

Application

Carl Jung made introversion and extraversion central attitude types in his theory of psychological types. Therefore, the classification named in the question is associated with Carl Jung.

Contrast

• Sigmund Freud: developed psychoanalysis and the structural account of id, ego, and superego, not this attitude-type classification.

• Norman L. Munn: wrote on general psychology and personality, but did not originate the introvert–extrovert typology.

• Gordon Allport: is chiefly associated with trait theory and individual dispositions rather than this two-orientation classification.

Cross-check

The decisive clue is the paired terms introversion and extraversion: they are the two opposing attitude orientations in Jungian psychological typology. Thus, Carl Jung is the answer.