Abstract
abstract: In response to recent interpretations of Thomas Aquinas’s account of the communication of idioms that have been advanced in the midst of conversation on the coherence of Chalcedonian Christology, this article seeks to show, first, that Thomas’s interpretation of the communication of idioms is at least internally consistent and, second, that his use of the medieval semantic distinction between signification and supposition, which has been given little attention in these recent interpretations, is the key to that consistency. By employing the distinction in correlation with his distinctions between essence and existence and between the intellectual operations of apprehension and judgment, Thomas is able to ensure that anything predicated of Christ (even predicated simpliciter ) applies to the one person of the Word as subsisting in either his human or his divine nature. Thus, I argue that Thomas’s semantic framework allows him to affirm, e.g., that Christ is mutable and Christ is immutable without contradiction, while it is the unique way in which this framework is applied to the Incarnation that lifts up the mystery.