Introversion

Three things in this short definition depart from ordinary usage. It is fear rather than preference, it concerns interaction rather than company and it has a stated cause, deanimation that the person has actually experienced. So introversion is not a temperament in Marsh's account but a learned response to social interactions that have drained rather than supplied. Its counterpart makes the axis explicit, since an extrovert is someone very receptive to anima from other people and an anima transfer in public gives them euphoria. Both terms therefore describe positions on one scale of prior experience rather than two types of person, and the position can move if the experiences change. Fear in the framework is anticipation of an attack on an anima source, so an introvert anticipating depletion from social contact is reading their history correctly rather than misjudging a neutral situation. The reasonable inference is that the environment is supplying more predation than connection. This also accounts for why the same person can be reliably drained in one setting and reliably energized in another without any change in disposition. What Marsh's account rules out is the usual consolation that introversion is simply a different and equally valid wiring, since on her reading it records something that happened.

Introversion in personality psychology is the low pole of extraversion, one of the five factors, measured by established scales, substantially heritable and stable across the lifespan and associated with differences in reward sensitivity. Jung's original usage concerned the direction of psychic energy, inward or outward, which is nearer to Marsh's framing. Susan Cain's popular account defends introversion as a valid disposition undervalued by extrovert-oriented institutions. Marsh's version cuts against both the trait literature and the popular defence, since making introversion an effect of experienced depletion implies it is neither inherited nor simply a difference to be accommodated, but evidence about what a person's interactions have been doing to them.