ontology

Any way of understanding the world, or some part of it, must make assumptions (which may be implicit or explicit) about what kinds of things do or can exist in that domain, and what might be their conditions of existence, relations of dependency, and so on. Such an inventory of kinds of being and their relations is an ontology. In this sense, each special science, including sociology, may be said to have its own ontology (for example, persons, institutions, relations, norms, practices, structures, roles, or whatever, depending on the particular sociological theory under consideration). The core of the philosophical project of metaphysics is to provide an ontology of the world as a whole. In some versions of metaphysics this takes the form of an attempt systematically to order the relations between the ontologies of the special sciences.