Perhaps the most important recent area of research in Scotus's philosophy has been in modal theory. There are two fundamental questions: To what extent does Scotus develop an understanding of modalities that is fundamentally logical, independent of states of affairs in the actual world? And to what extent are modal concepts dependent on divine causal activity? The two questions are distinct, in the sense that the first is about the definition of the various modal terms, whereas the second is about the explanation for the fact that there are modalities at all. If God were to cause modalities, then he would also cause the property of conceivability that is the mark of logical possibility. The first question, in particular, has important ramifications for Scotus's theory of the freedom of the will.

As always with Scotus, these questions do not admit of straightforward...