Abstract

Contingency is encountered in the world, but the nature of such an "encounter" is ontologically obscure. In particular, contingency seems to commit us to granting existence to "possibilities" in order to distinguish the sphere of mere non-being from the sphere of that which is not, but "could be." ;Through detailed analyses of Aristotle and Duns Scotus this dissertation departs from the dominant contemporary interpretation of modalities , according to which Scotus rejected the so-called "principle of plenitude" attributed to Aristotle and replaced the ancient "diachronic theory of possibilities with a "synchronic" one, thereby contributing to a "possible worlds semantics." The dissertation shows that the question of possibility, in its proper ontological import, concerns the "limit" between being and non-being in their essential separation. ;Contingency is thus explored in Aristotle with a particular attention to "time," " kairo&d12; v ," "disposition," and "matter." In the context of Scotus, the ontological status of possibilities is understood in terms of "will," "creation," "omnipotence," and "freedom." With Scotus, possibilities become the horizon of what is supremely actual . What appeared as a lesser or lower being becomes a sign of omnipotence. The dissertation attempts then: To account for this transformation by focusing on the difference between the Aristotelian concept of , a&d12;p3 iron and that Medieval idea of ens infinitum; and To trace the problem back to the question of the unity of being . ;Finally, the origin of the essential divide within being between du&d12;na miv and 3 ,n3&d12;r g3ia is discussed in terms of a confrontation with the impossible from which, the dissertation suggests, derives the modal ontological distinctions.