A social system basically consists of two or more individuals interacting directly or indirectly in a bounded situation. There may be physical or territorial boundaries, but the fundamental sociological point of reference is that the individuals are oriented, in a whole sense, to a common focus or inter-related foci. Thus it is appropriate to regard such diverse sets of relationships as small groups, political parties and whole societies as social systems. Social systems are open systems, exchanging information with, frequently acting with reference to other systems. Modern conceptions of the term can be traced to the leading social analysts of the nineteenth century, notably Auguste Comte, Karl Marx, Herbert Spencer and Emile Durkheim; each of whom elaborated in some form or other conceptions of the major units of social systems (mainly societies) and the relationships between such units- even though the expression social system was not a key one. Thus, in Marx's theory, the major units or components of the capitalist societies with which he was principally concerned were socio-economic classes, and the major relationships between classes involved economic and political power.
The most influential conceptualization of the term has been that of Talcott Parsons. Parsons' devotion to this issue has two main aspects. First, what is called the problem of social order; i.e. the nature of the forces giving rise to relatively stable forms of social interaction and organization, and promoting orderly change. Parsons took Thomas Hobbes Leviathan, 1651, as his point of departure in this part of his analysis. Hobbes had maintained that man's fundamental motivation was the craving for power and that men were always basically in conflict with each other. Thus order could only exist in strong government. To counter this Parsons invoked the work of Max Weber and, in particular, Durkheim, who had placed considerable emphasis on the functions of normative, factors in social life, such as ideals and values. Factors of this kind came to constitute the mainspring in Parsons Delineation of a social system. Thus in his major theoretical work, The Social system, 1951, he defines a social system as consisting in a plurality of individual actors interacting with each other in a situation which has at least a physical or environmental aspect, actors, who are motivated in terms of a tendency to the optimization of gratification and whose relations to their situations, including each other, is defined and mediated in terms of a system of culturally structured and shared symbols.
The major units of a social system are said to be collectivities and roles (i.e. not individuals as such); and the major patterns or relationships linking these units are values (ends or broad guides to action) and norms (rules governing role performance in the context of system values). Parsons second major interest has been to make sociology more scientific and systematic, by developing abstract conceptions of the social system; one of this points being that even though Weber placed much emphasis upon normative factors as guiding action, there was in Weber's sociology no elaboration of a theoretically integrated total system of action.
Hence the attempt to combine in one framework both a conception of actors in social situations and an overall, highly abstract, outside view of the major factors involved in a social system as a going concern. Various points in Parsons' formulation have been criticized. Notably, objections have been made to the emphasis upon normative regulation, and it has been alleged that Parsons neglected social conflict under the pressure of his systematic perspective; i.e. pre-occupation with system ness and analytical elegance which blinds the sociologist to disconsensus in real life and spurs him to stress integrative phenomena in his analyses. However, it is widely agreed that sociologists should operate with some clearly defined conception of what constitutes a social system. Thus, for many sociologists the term social system is not by any means restricted to those situations where there is binding normative regulation; but in order to qualify as social system it must involve a common focus, or set of foci, or orientations and a shared mode of communication among a majority of actors. Thus, on this basis there can be a system of conflict.