Type Dynamics refers to the interrelationship among the four cognitive functions in a psychological type. Far from being a simple combination of initials, the full type creates a rich, interwoven system of perceiving and judging that explains much of the similarity and difference among the types. Type Dynamics has garnered little to no empirical support to substantiate its viability as a scientific theory. Nonetheless, it remains deeply entrenched in the Myers-Briggs community. Some practitioners argue that type dynamics is supported by qualitative evidence (such as observed psychological dysfunction in individuals). Type dynamics posits that the psyche has mental functions arranged hierarchically in a function stack and that the functions operate in a series of pairs or axes.