Continuum (theory) in the context of "Extraversion"

Space is a three-dimensional continuum containing positions and directions. In classical physics, physical space is often conceived in three linear dimensions. Modern physicists usually consider it, with time, to be part of a boundless four-dimensional continuum known as spacetime. The concept of space is considered to be of fundamental importance to an understanding of the physical universe. However, disagreement continues between philosophers over whether it is itself an entity, a relationship between entities, or part of a conceptual framework.

In the 19th and 20th centuries mathematicians began to examine geometries that are non-Euclidean, in which space is conceived as curved, rather than flat, as in the Euclidean space. According to Albert Einstein's theory of general relativity, space around gravitational fields deviates from Euclidean space. Experimental tests of general relativity have confirmed that non-Euclidean geometries provide a better model for the shape of space.

Extraversion and introversion are a central trait dimension in human personality theory. The terms were introduced into psychology by Carl Jung, though both the popular understanding and current psychological usage are not the same as Jung's original concept. Extraversion (also spelled extroversion) is typically associated with sociability, talkativeness, and high energy, while introversion is linked to introspection, reserve, and a preference for solitary activities. 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".

While often presented as opposite ends of a single continuum, many personality theorists, such as Carl Jung, have suggested that most individuals possesses elements of both traits, with one being more dominant. 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 psychology, personality type refers to the psychological classification of individuals. In contrast to personality traits, the existence of personality types remains extremely controversial. Types are sometimes said to involve qualitative differences between people, whereas traits might be construed as 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.