Ontology, Epistemology, and Multimethod Research in Political Science

Epistemologies and research methods are not free of metaphysics. This is to say that they are both, supported by (or presumed by), and support (or presume) fundamental ontologies. A discussion of the epistemological foundations of "multimethod" research in the social sciences-in as much as such research claims to unearth "causal" relations-therefore cannot avoid the ontological presuppositions or implications of such a discussion. But though there isn't necessarily a perfect correspondence between ontology, epistemology, and methodology, they do constrain each other. As such it is possible to make methodological choices that are at odds with one's (implicit) ontology or argue from an ontology that is inconsistent one's choice of methods. Yet lack of recognition of this fact has hampered methodological discussions in political science, especially with respect to the discussion on the merits of multimethod research. The ontology implicitly accepted in such discussions is "reductionist" and "regularist," that is, one that respectively defines causes in terms of noncausal relations and states of affair and affirms that such noncausal relations are regularities in nature. This article will argue that any attempt to fit "multimethod" research (where "multimethod" signifies some combination of inferential statistics and case studies) within this narrow ontology is destined to fail since such a metaphysics logically cannot accord case studies a necessary or sufficient role in the in the establishment of causal relations. However, there are metaphysical positions within the ambit of an empiricist philosophy of science that can accommodate multiple methods without contradiction. The article discusses two such ontologies and suggests ways in which they might allow the establishment of a coherent epistemological foundation for multimethod research, however, within a decidedly empiricist philosophy of science.