Afterword: Ontological, epistemological and sociological dimensions of domains

Domains are basically constituted of three kinds of theories and concepts: (1) ontological theories and concepts about the objects of human activity; (2) epistemological theories and concepts about knowledge and the ways to obtain knowledge, implying methodological principles about the ways objects are investigated; and (3) sociological concepts about the groups of people concerned with the objects. There are complicated relations between these elements. Basic theories about those relationships are, for example, forms of philosophical realism and social constructivism. In this paper these concepts and theories are introduced, and their implications for knowledge organization outlined, with illustrations drawn from this special issue of Knowledge Organization.