An Analysis of Ibn Sīnā’s Theory of Emanation in Light of Aquinas’ Criticisms

There have been two main responses to the question of how existence other than God came about: 1) Creation that occurred directly and out of nothing at once; 2) the emanation theory that existence gradually proceeded in a way of overflowing from the First. While one of the most important concerns of the creation theory is the categorical distinction of God from His creatures and the preservation of His creative attribute, the underlying characteristic of the emanation theory, which is grounded on the idea of God’s absolute simplicity, is the claim that everything gradually emanated from the ultimate source, that is, God. İbn Sīnā, who is the most prominent representative of the emanation theory in Islamic thought, re-interpreted certain philosophical issues of emanation in accordance with Islamic theology. In this study, I first evaluate and discuss the main lines of Avicenna’s emanation theory, and then discuss the value of Aquinas’ criticisms on such issues as the necessary procession of things without will, inexplicability of the multiplicity of things through the principle that ‘only one can proceed out of one,’ and whether or not there is an aim in emanation.