Abstract

One often hears extravagant claims made for the Aristotelian doctrine that "what understands and what is understood are the same" De anima iii.4; 430a4). This identity between knower and what is known, or between percipient and what is perceived, is often said to offer a way out of the familiar skeptical arguments against the possibility of our having knowledge of the external world. Typically such claims are made by students of Thomas Aquinas, who in this way seek to render Aquinas's theory of knowledge immune from the skeptical and idealist controversies of modern philosophy. In this paper I argue that Aquinas put this doctrine of identity to no such use, that in fact he explicitly rejects any such use of the doctrine, and that furthermore no plausible reading of the doctrine could conceivably produce such dramatic results.