The Identity of Knower and Known: Sellars’s and McDowell’s Thomisms

Wilfrid Sellars’ engagement with Thomism in “Being and Being Known” is examined, specifically for his reformulation of the thesis that the mind in its mental acts is in some sense identical in form to the object known. Borrowing the notion of “isomorphism” from modern set theory, Sellars describes an identity of form between mind and world that is non-intentional in the “Realm of the Real,” while confining all questions of meaning and truth to the “Realm of the Intentional.” John McDowell’s response to Sellars’ reformulation is then examined. McDowell is critical of Sellars’ “blind spot” on the normativity of truth, and argues for the embedding of the intentional in the Realm of the Real under the guise of truth. This paper notes difficulties with both authors’ discussions. Both authors are misled in their discussions of Aquinas by an overemphasis upon the “mental word” as described by Peter Geach. In addition it is proposed that Sellars’ notion of “isomorphisms” has the additional problem of adequately distinguishing various types of mental statements as neural states in the Realm of the Real. The paper concludes by arguing for a deep affinity between McDowell and Aquinas on the normativity of truth.