Avicenna and the Distinction Between the Necessary Being and the Possible Being

Abstract

The aim of this article is to approach the distinction between the necessary being and the possible being from Avicenna’s Metaphysics (Ilāhiyyāt) translated into Latin as Philosophia prima sive scientia divina. In order to investigate the hypothesis that this Avicennian distinction influenced the third demonstration of God’s existence proposed by Thomas Aquinas in his Summa Theologica Ia, the text is divided into four parts. The first part provides a historiographical justification for the direct and indirect relationship between Thomas Aquinas and Avicenna. It is a complex subject since it involves not only the reception of Avicenna’s metaphysical text, but also the reception of Avicenna’s metaphysical ideas, which began to be incorporated into the vocabulary of Jewish and Christian philosophers from the 11th-12th centuries. In the second part, I reconstruct the context in which Avicenna inserts the distinction between the possible being and the necessary being starting from Metaphysics I, when Avicenna tries to relate the notion of being to the notions of necessary and thing. In the third part, I discuss some important developments of this distinction for the Gods’ existence demonstration in Metaphysics VIII based on the connection between the existence of an efficient first cause and the necessary being per se. Finally, at the end of the text, I return to the comparison with the third way found in the Summa Theologica Ia to show that the demonstration of God’s existence in Avicenna’s text is different from the Summa Theologica.