Abstract

Reductionism concerns a set of ontological and epistemological claims, and methodological strictures based on them, about the relationship between two different scientific domains. The critical assumption is that one of these domains is privileged over the other in the sense that the concepts, rules, laws, and other elements of the privileged domain can be used to specify, constitute, or account for those of the other “reduced” domain. This specification often consists of explanation, such that the “reducing” domain is epistemically privileged over the reduced one. Explanations of this type are “reductionist” (or, are “reductions”) and reductionism is then the thesis that such explanations will always be forthcoming or at least are possible in principle. Reductionism is most plausible if the entities of the reduced domain can be interpreted as arising from (e.g., as aggregates of) entities of the reduced domain. This ontological claim is controversial but motivates many reductionist theses and associated scientific research programs. Thus, epistemological and ontological claims about reductionism have the methodological implication that they should govern and guide scientific research. When such research proves to be fruitless over a period of time, the associated reductionist claims themselves become suspect. Although issues connected with reductionism arise in the physical and social sciences, most attention to reductionism in philosophy of science over the last few decades has focused on the biological sciences, especially after the advent of molecular biology made it plausible to believe that biological phenomena can be uniformly explained (in detail) from their physical basis. However, the program of finding such explanations has a long philosophical history often couched in terms of seeking “mechanical,” “mechanistic,” or “materialistic” explanations. The contrast here is with traditional vitalism and various forms of teleology and holism.