Co-reference and the identity of propositions

Abstract

To the believer in propositions no problem is more acute than that of specifying the conditions under which two sentences may be said to express the same proposition. As with any general problem, some enlightenment may be expected from the scrutiny of special cases. And where propositions are concerned, the most natural place to begin the search for a criterion of their identity is with sentences of particularly "simple" kinds. One especially interesting variety of sentence is that in which the logical subject is a uniquely referring expression. In his recent paper, 'Reference and Propositional Identity '1 , Edgar Page attempt s to settle the question of when two sentences of this variety express the same proposition insofar as the answer hinges merely on consideration of the uniquely referring expressions involved. In what follows I shall be concerned with Page's proposed identity-criterion exclusively from the standpoint of evaluating its alleged consequences. Section II offers a brief summary and explanation of the identity-criterion itself. Section III discusses a putative corollary to the criterion and indicates its highly counterintuitive character. Section IV explores Page's argument for accepting this corollary. Finally, Sections V and VI present arguments from two different perspectives to demonstrate that Page's defense of the alleged corollary is unsound and self-defeating.