[clarification needed] He seems to have had advanced knowledge of philosophy of theology, but again it is unclear where he might have completed his studies.
[2] Only John the Canon's extensive commentary on Aristotle's Physics has survived (Quaestiones libri Physicorum).
John's commentary seems to have been inspired by Duns Scotus, who himself never seems to have written an independent treatise on physics.
Recent research has shown that John extensively cites other authors in his questions, which makes him a privileged source for the study of fourteenth century philosophy and theology.
[2] In many of these cases, John's treatise, which was moderately famous in his own time, was better known than these author's own works.