The Kantian Project in Modern International Legal Theory

Abstract

Developments over the last 50 years in the institutional nature of international law and the political situation it regulates have led to a revival of Kant’s approach to international legal theory. Kant’s argument requires, first, that a distinction is made between just and unjust states for the purposes of regulation by international law and, secondly, that international law must be institutionally designed to ensure the peaceful settlement of disputes. Fernando Teson’s A Philosophy of International Law — which is the subject of this review — represents the fullest defence of Kant’s international legal theory yet. It is argued in this review that Teson’s work contains two problems. First, Teson does not defend the methodological and justificatory basis of Kantian theory which is, on most accounts, the categorical imperative, and his allusion to an empirical methodology is problematic. Secondly, Teson does not sufficiently develop the second of Kant’s major theses, which concerns the maintenance of peace by international legal institutions. In fact, Teson’s argument can be best understood as an account of a Kantian approach to a moral foreign policy rather than a Kantian conception of international law.