What, if anything, do historians and theorists of international relations owe to the theories and practices of the Middle Ages? This paper traces a number of themes that were intensely debated by theologians during the fourteenth century, tracking especially two different approaches to ‘the political’ on the part of neo-Augustinian voluntarists on the one hand and neo-Aristotelian intellectualists on the other. In the scholastic attempts to answer the question: ‘What are we presumed to be? And, in consequence, what is the scope of politics?’, their different views concerning the consequences of what Christians call ‘Original Sin’ and ‘the Fall’ are highlighted. Especially, the position of the voluntarists is shown to have been taken up not least by the Master of the Modern: Hobbes. The neo-Augustinian voluntarists can thereafter be seen to have provided some of the same arguments that have recently been rehearsed by contemporary ‘realist’ critics of modern liberalism who, it is argued, are negotiating the medieval in the modern.