Introduction

In Lectura I 39.56 and 59 we notice quite an interesting feature: in reply to an objection to his theory of synchronic contingency (§§38–54) the young John Duns rejects a certain rule of logic. He also mentions the ars the rule under consideration belongs to:

We observe that Duns is generous in his praise regarding the master who evidently was an expert in the field: a certain magister handed down the ars obligatoria very well. Apart from the term ‘magister’ in the expression ‘Magister Sententiarum,’ ‘magister’ refers to a philosopher, ‘philosopher’ taken in the modern sense of the word. With Duns, ‘magister’ refers to a philosopher and ‘doctor’ refers to a theologian. So the master referred to taught the ars obligatoria, but what does the ars obligatoria consist of?

The development of the ars obligatoria presupposes an ongoing development of the academic practice of debate and rational refutation. Theory sponges on reality. In matters theoretical, theory is parasitic on the practice of the theory. Subjects of theoretical reflection presuppose the inner dynamics of a practice wherein the art of debate, disputation, and refutation developed itself. The reality of an academic debate culture has to be considered the habitat of a growing ars obligatoria.