International Encyclopedia of Systems and Cybernetics

"A social system composed of human beings and their artifacts" (M. BUNGE, 1993, p.212).

M. BUNGE distinguishes among human social systems:

"1. Natural or spontaneous if and only if it is self -organized (i.e. if it emerges spontaneously by reproduction, accretion or self-assembly)". BUNGE's examples are: "Families, street-corner gangs, and bands of hominids".

"2. Artificial or formal, or an organization if and only if it is other-organized, i.e. set up and maintained according to explicit plans and rules". BUNGE's examples: "Schools, churches, business firms, and government departments are artificial systems" (Ibid).

E. JANTSCH and C. WADDINGTON considered however that: "The evolutionary paradigm is still almost totally neglected by a social science which finds its purpose in reducing the human world to the equilibrium perfection, structural unambiguity and permanence, hierarchical control, and predictability of machine-like structures" (1976, p.2).

G. VICKERS also insists on the dynamical nature of the human social system and describe it as: "… a set of ongoing relations between persons and organizations, governed by mutual expectations which are usually embodied in roles. It is of course a very complex pattern. Each of us forms part of several subsystems and each of these is incorporated in varying degrees in others…

"… we distinguish something that we regard as a continuing entity but only to the extent and in the field in which it maintains, through time two sets of relationships which are themselves intimately linked – the internal ones which relates its members to each other and the external one which links it, as a whole, to its surround. The entity is in fact a pattern of relationships, subject to change, but recognizably extend in time" (1967, p.59).

Such a description seems to fit however any social system, be it a trade-union, a beehive or even possibly, up to a point an ecosystem or a brain.

In a closely related sense, T.R. YOUNG and G. SWARTZMAN observe that "… all social systems depend upon information flow in order to survive as thermodynamical entities" (1974, p.259).

Organizationally closed values subsystems are the most important sources of such information flows in socio-cultural or socio-historic systems. Information flows also seem to exist in insect societies, albeit in different forms.

In the restricted sense of human systems, R.L. ACKOFF and F.E. EMERY propose the following definition: "A system whose elements are purposeful individuals" (1972, p.215).