Siger of Brabant (c.1240–c.1284)

Born probably circa 1240 in the Duchy of Brabant, Siger of Brabant studied philosophy in the arts faculty at the University of Paris and became regent master there in the 1260s. Various positions which he defended were included in Bishop Etienne Tempier’s condemnations of 1270 and 1277, and he appears to have fled France when cited to appear before the French inquisition. He probably spent his final days in Italy, and died there before November 1284.

As a professional teacher of philosophy, Siger regarded it as his primary mission to lecture on Aristotle and other philosophers and to present their views on the points at issue. Early in his career he defended some of the positions condemned by Bishop Tempier, but after 1270 he often nuanced his exposition of such views by noting that he was only presenting the views of the philosophers or of Aristotle, or that he was proceeding philosophically in these discussions. Often regarded as a leading Latin ‘Averroist’, he agreed with Averroes that there is only one human intellect, though he eventually reversed his view on this. His personal philosophy is strongly Aristotelian, but with various elements derived from Neoplationism.

On the relationship between essence and existence in created beings, Siger denies that existence is something added to a thing’s essence and holds that the existence of such entities belongs to their essence. He holds that one can demonstrate God’s existence, but insists that Aristotle’s physical argument for a First Mover must be completed by metaphysical argumentation. While denying that human beings in this life enjoy any direct knowledge of the divine essence, he seems open to Averroes’ view that they can reach some knowledge thereof.