Interroga virtutes naturales: Nature in Giles of Rome’s On Ecclesiastical Power

Giles of Rome’s On Ecclesiastical Power (De ecclesiastica potestate), a polemical work arguing for the political supremacy of the pope, claims that the papacy holds a ‘plenitude of power’ and has direct or indirect authority over all aspects of human life. This paper shows how Giles uses themes from natural philosophy in developing his argument. He compares cosmic and human ordering and draws an analogy between the relations of soul to body and of Church to state. He also understands the pope’s power to be ‘universal’ in nature, another idea taken from Aristotelian physics. Further, Giles views the pope’s right to intervene arbitrarily in the affairs of the Christian community as mirroring God’s ability to work miracles. We thus see that Giles, no less than intellectuals on the other side of this debate such as Dante and Marsilius of Padua, believed that Aristotelian natural philosophy could be enlisted in the service of political thought.