Duns Scotus on Metaphysical Potency and Possibility

DUNS SCOTUS ON METAPHYSICAL POTENCY AND POSSIBILITY That Duns Scotus's thought marks a turning point in the understanding of modality has ensconced itself among the commonplaces of history of medieval philosophy, a fact almost entirely due to the efforts of Simo Knuuttila.1 But if debate over -whether Duns altered the course of thought on this critical area of philosophy has virtually disappeared, confusion seems still to reign about exactly what sort of change he wrought. At the international conference on Scotus's metaphysics and ethics held in 1994 at the University of Bonn, no less than three different interpretations of his pathblazing efforts were offered, one by Knuuttila himself, another by Knuuttila's habitual interlocutor on this issue, Calvin Normore, and a third by John Boler.2 I, too, had something to say about Scotus and modality at the Bonn conference, but there I kept my assessment of his philosophical accomplishment tributary to Knuuttila's, focusing instead on the ambiguous historical links between Duns's ideas on the matter and the precedent work of Henry of Ghent.3 It is time, I believe, that I turn my attention to the issue under debate. Having thought about the Bonn papers for a long time, I have come to the conclusion that there is something more to be said. Perhaps immodestly, I think I can bring us a step closer to resolving the 'See Simo Knuuttila, "Time and Modality in Scholasticism," in Reforgtng the Great Chain of Being. Studies m the History of Modal Theory, ed. Simo Knuuttila, 163257 (Dordrecht, 1981); "Modal Logic," in The Cambridge History of Later Medieval Philosophy, ed. Norman Kretzmann et al., 342-57 (Cambridge, 1982); "Being qua Being in Thomas Aquinas and John Duns Scotus," in The Logic of Being. Historical Studies, ed. Simo Knuuttila and Jaakko Hintikka, 201-22 (Dordrecht, 1986); and Modalities in Medieval Philosophy (London, 1993). 2See Simo Knuuttila, "Duns Scotus and the Foundations of Logical Modalities," in John Duns Scotus. Metaphysics and Ethics, ed. Ludger Honnefelder, Rega Wood, and Mechthild Dreyer, 127-43 (Leiden, 1996); Calvin G. Normore, "Scotus, Modality, Instants of Nature and the Contingency of the Present," ibid., 161-74; and John Boler, "The Ontological Commitment of Scotus's Account of Potency in his Questions on the Metaphysics, Book DC," ibid., 145-60. 3See my "Revisiting Duns Scotus and Henry of Ghent on Modality," in Metaphysics and Ethics, 175-89. 265 Franciscan Studies, Vol. 56 266Steven P. Marrone disagreement, and I attempt to do so—with maybe more appropriate humility—by drawing a bit on each of my three distinguished colleagues. Since Knuuttila invented the idea of Scotus as a crucial innovator on modality, it makes sense to start with his views about the nature of the innovation. By his account, before Duns modal theory never wandered beyond the philosophical bounds set by the ancients, most plainly apparent in Aristotle's so-called statistical approach, whereby what always was or would be was necessary and what never was nor would be was impossible, between which extremes ranged the spectrum of possibility, founded on the minimal actuality of what was or would be for at least a single moment of time. Duns Scotus shattered the intellectual tyranny of this position, first by denying the necessity of the present and then by laying out a systematic conception of synchronic alternatives. Freed from the metaphysical commitments of the ancient view, he thus began to formulate a definition of possibility based on logical coherence rather than conditions of actuality, cutting modality off from the question of existence and giving it a theoretical status independent of metaphysics, or more precisely, ontology.4 Calvin Normore has consistently criticized Knuuttila on this last point. According to his reading, Scotus never severed the link between modality and actuality. As with the ancients, possibility for Duns was always to be referred to a power possessed by something, so that in some sense actual existence had to be prior to and foundational for possibility.5 Normore goes on to re-examine Scotus's rejection of the necessity of the present, explaining that he managed to do this not by establishing possibility on the logical analysis of semantic alternatives but...