ABSTRACT
Perhaps the most important and certainly famous philosophical doctrine of Ibn Sīnā (in Latin, Avicenna) is his teaching on essence (dhāt) or, better, quiddity (māhiyya) and existence (wūjūd). When considered metaphysically, each and every being (mawjūd) in the universe is one of two kinds:
Everything other than God, from the lowest type of material thing to the highest angel, is a being composed of two ontological principles: quiddity and existence. In such composed beings, their existence is ontologically “other” than their quiddity. Consequently, such a being must be made to exist by some external efficient cause giving it existence.
By contrast, God is “entirely one” and is not in any way composed of diverse ontological principles, such as quiddity and existence. His “existence is not shared by any other” being. Consequently, there can be no cause of God’s existence. Rather, God is the ultimate cause of the existence of every other being (Avicenna 2005: 38; all translations in this article are mine).
By explaining the difference between God and all other things in this way, Ibn Sīnā was able to devise a philosophical explanation of creation, one that in no way involved a beginning of the created world at a first moment in time, which is how most earlier Muslims and Christians had thought of creation.