1. This threefold division derives from Martin Wight. The best published account of it is his ‘Western Values in International Relations’, in Diplomatic Investigations, ed. Herbert Butterfield and Martin Wight (London: Allen & Unwin, 1967). The division is further discussed in my ‘Martin Wight and The Theory of International Relations. The Second Martin Wight Memorial Lecture’, British Journal of International Studies, vol. II, no. 2 (1976).
2. In Kant’s own doctrine there is of course ambivalence as between the universalism of The Idea of Universal History from a Cosmopolitical Point Of View (1784) and the position taken up in Perpetual Peace (1795), in which Kant accepts the substitute goal of a league of ‘republican’ states.
3. Otto Gierke, Natural Law and the Theory of Society 1500 to 1800, trans. Ernest Barker (Boston: Beacon Press, 1957) p. 85.
4. See ‘Third Letter on the Proposals for Peace with the Regicide Directory of France’, in The Works of the Right Honourable Edmund Burke, ed. John C. Nimmo (London: Bohn’s British Classics, 1887).
5. E. de Vattel, The Law of Nations (1758) Introduction, translated by Carnegie Institute (1916) p. 3.