Concepts originating in the philosophy of science generally are used only ritualistically and in careful isolation from research practice in political science. But philosophical considerations are fundamental to political research, and critically influence its decisions. The question is whether ideas offered by philosophers of science have practical (that is to say, theoretical) significance for political researchers. This essay argues that philosophy of science has extremely relevant ideas to offer. The argument proceeds through an initial presentation of some elementary notions drawn (...) from reconstructions of the nature of concept formation-theory construction. These are then utilized in a critique of the research of quantitative political scientists. Three rather central concerns of this, still very young, discipline are discussed: measurement problems, the use of recursive and structural systems in causal modeling, and the primary logical function of multivariate analysis in political studies. The discussion is viewed as supporting the general point that applied philosophy of science ought to be, not an adjunct, but one of the key critical contributors to political research. (shrink)