 At the beginning the Essay, Condillac demonstrated that the soul is immaterial, in opposition to Locke’s hypothesis of thinking matter. According to Condillac, God cannot give to matter the power to think. The operations of thought show by themselves the unity of consciousness, and the unity of consciousness is only accountable by presupposing a simple and indivisible subject of inherence for consciousness itself. Condillac presents this line of argument by saying that individual perceptions are indivisible in their nature and so they cannot inhere in different substances. Even assuming that each individual perception inheres in a separate individual substance, the act of comparing perceptions could not occur without a simple and indivisible substratum. “However, a mass matter is not one; it is a multitude” or, as Condillac also said, matter is an assemblage or collection of things (Essay I.i.1 §6). Therefore, the soul must be an immaterial substance.