The procedure he adopted to analyze this system and its subsystems is called the "AGIL Paradigm" or "AGIL scheme". To survive or maintain equilibrium with respect to its environment, any system must to some degree adapt to that environment (Adaptation), attain its goals (Goal attainment), integrate its components (Integration), and maintain its latent pattern (Latency pattern maintenance), a cultural template of some sort. These are called the system's functional imperatives.
In the case of the analysis of a societal action system, the AGIL Paradigm, according to Parsons, yields four interrelated and interpenetrating subsystems: the behavioral systems of its members (A), the personality systems of those members (G), the society as a system of social organization (I) and the cultural system of that society (L). To analyze a society as a social system (the I subsystem of action), people are posited to enact roles associated with positions. These positions and roles become differentiated to some extent and in a modern society are associated with such things as occupational, political, judicial and educational roles.
Considering the interrelation of these specialized roles as well as functionally differentiated collectivities (e.g., firms, political parties), the society can be analyzed as a complex system of interrelated functional subsystems, namely:
• The economy -- societal adaptation to its action and non-action environmental systems
• The polity -- societal goal attainment
• The societal community -- the integration of its diverse social components
• The fiduciary system -- processes and units that function to reproduce societal culture
Parsons elaborated upon the idea that each of these systems also developed some specialized symbolic mechanisms of interaction analogous to money in the economy, e.g.., influence in the societal community. Various processes of "interchange" among the subsystems of the societal system were...