ABSTRACT
In this chapter we give an overview of the problem of conceptual change in 20th-century philosophy of science. The problem of conceptual change has been widely discussed in the philosophy of science since the early 1960s, when Thomas Kuhn and Paul Feyerabend, among others, launched a powerful critique of logical positivism. One of their most far-reaching theses was that scientific concepts are historical entities that evolve over time and are replaced by altogether different ones. In their view, the older concepts and their descendants refer to completely different entities. The very subject matter of scientific investigation shifts along with conceptual change. Furthermore, because of such ontological shifts, the possibility of giving an account of theory change as a rational process is undermined. In post-Kuhnian philosophy of science there has been considerable effort to come to terms with these ontological and epistemological implications of conceptual change.
