Knowledge and Class sees itself as a central work of �new Marxian political economy� using the central concept of �overdetermination� against essentialism and determinism in orthodox �classical� Marxist political economy. For the authors, both humanism and empiricism are seen as essentialist. The general epistemological pluralist conception of truth is a foundation stone for analysising class structure of societies. Class is constistuted at multiple levels and can no longer be regarded in a �dualist� and reductionist manner. Much indebptedness is expressed for the work of Louis Althusser for providing the framework wherein post-modernism and post modern Marxism can intersect. Witness in Callari & Ruccio (1994) the constructed reading of Althusser in pluralist; anti-positivist and essentialist manner. So central is the usage of overdetermination that they almost attribute to Althusser as having already dealt with the modernist/postmodernist debate, alkbeit not in the terms as expressed.