will refer to those processes which tend to elaborate or change a system's given form, structure, or state. - Walter F. Buckley

The more recent concern with complex adaptive organization has led to the notion of contingency as the important key. Thus Wiener, while working in the field of communications and probability theory, became convinced 'that a significant idea of organization cannot be obtained in a world in which everything is necessary and nothing is contingent'

Prestige rests upon interpersonal recognition, always involving at least one individual who claims deference and another who honours the claim... Status groups treat of each other as social equals, encouraging intermarriage of their children, joining the same clubs and associations, and participating together in such informal activities as visiting, dances, dinners and receptions.

Adaptive system — whether on the biological, psychological, or sociocultural level — must manifest (1) some degree of "plasticity" and "irritability" vis-a-vis its environment such that it carries on a constant interchange with acting on and reacting to it; (2) some source or mechanism for variety, to act as a potential pool of adaptive variability to meet the problem of mapping new or more detailed variety and constraints in a changeable environment; (3) a set of selective criteria or mechanisms against which the "variety pool" may be sifted into those variations in the organization or system that more closely map the environment and those that do not; and (4) an arrangement for preserving and/or propagating these "successful" mappings.