Part I Histories, Ch.9 Early Twentieth-Century Positivism Revisited

Subject(s):

Customary international law — General principles of international law — Sources of international law

This chapter focuses on Lassa Oppenheim’s (1858–1919) groundbreaking work on the legal theory of international law, which was written at the beginning of the twentieth century. Oppenheim’s recognition of the economic interdependence of nations was one important factor in his success in establishing the international economic system as the supporting framework of his Family of Nations, and as the underlying theory of his international law. Afterwards, the chapter maps the complex legal theoretical transition embedded in the change of philosophical position as regards the understanding of universalism. This involves a move from the transcendent realist philosophy of an earlier era to the immanent philosophy of the Austrian positivists at the beginning of the century.