1. Augustine, The City of God, bk xix, ch. XII (Everyman’s Library, 1950) p. 249.
2. There are many sources for this analysis, but see especially H. L. A. Hart’s account of ‘the simple truisms’ that constitute ‘the core of good sense in the doctrine of Natural Law’: The Concept of Law (Oxford: Clarendon Press, 1961) p. 194.
3. For an attempt to view international relations as a special case of the relations of powers, see Arthur Lee Burns, Of Powers and their Politics: A Critique of Theoretical Approaches (Englewood Cliffs, N.J.: Prentice-Hall, 1968).
4. Raymond Aron, Peace and War: A Theory of International Relations (London: Weidenfeld & Nicolson, 1966) p. 94.
5. See Martin Wight, Systems of States (Leicester University Press and London School of Economics, 1977) ch. 1.