Charles Covell considers the poltical thought of Thomas Hobbes in relation to the tradition of international law, and with the intention to challenge the reading of Hobbes as the exponent of the realist standpoint in international thought and practice. The relation of Hobbes to international law is explained through attention to the place that he occupies among the modern secular natural law thinkers, such as Grotius, Pufendorf, Wolff and Vattel, who founded the modern system of the law of nations.

The Defence of Natural Law comprises a study of the philosophies of law expounded by Lon L. Fuller, Michael Oakeshott, F.A. Hayek, Ronald Dworkin and John Finnis. The work of these theorists is situated in relation to the modern tradition in legal philosophy. In this way, it is demonstrated that the theorists adhered closely to the natural law standpoint in legal philosophy, while also defending the particular view of the proper functions of law and the state that distinguished the tradition of modern liberalism.