I offer a social ontology that I refer to as methodological localism (ML). This theory of social entities affirms that there are large social structures and facts that influence social outcomes. But it insists that these structures are only possible insofar as they are embodied in the actions and states of socially constructed individuals. The “molecule” of all social life is the socially constructed and socially situated individual, who lives, acts, and develops within a set of local social relationships, institutions, norms, and rules. (link)
The presentation sketches a view of how to think about higher-level features of social life -- institutions, organizations, ideologies, normative frameworks, systems of power, and large-scale social structures. Each of these aspects of the social world is recognized as "real"; but it is emphasized that we need to understand the workings of these "higher-level" social entities in terms of the beliefs, ideas, and situations of the individual actors who play roles within them. Institutions are indeed a kind of mutually supporting "house of cards" (in James Coleman's phrase; link), in which the causal power of institutions to shape and motivate future individuals depends upon the corresponding features of agency and motivation possessed by current individuals.
This simple ontology implies a broad orientation for research in sociology: to uncover the concrete and specific characteristics of social arrangements at all levels. This includes such things as the specifics of the arrangements through which individuals acquire their ways of thinking and acting in the world, and the arrangements that constitute the fields of incentives, opportunities, rules, and resources through which they live their lives. Turning attention to the higher-level "assemblages" of actors (organizations, institutions, ideologies, normative frameworks, systems of power), the actor-centered approach requires that we pay attention to the ways in which high-level causal powers disaggregate across networks and systems of socially related individual actors.