 The process of intellectual cognition of an essence involves two operations that correspond to two different powers of the intellectual faculty: the operations of abstraction and intellection by the agent and the possible intellect. Since the essence in both the image and the external thing has material existence, and since the object of intellectual cognition must be immaterial, it is necessary to introduce a power that makes the essence immaterial. This power is the agent intellect—an active power that, through the act of abstraction, makes immaterial the essence materially represented in the image (QDA-1974-III: 212).