John Perry

When you use the word “I” it designates you; when I use the same word, it designates me. If you use “you” talking to me, it designates me; when I use it talking to you, it designates you. “I” and “you” are indexicals. The designation of an indexical shifts from speaker to speaker, time to time, place to place. Different utterances of the same indexical designate different things, because what is designated depends not only on the meaning associated with the expression, but also on facts about the utterance. An utterance of “I” designates the person who utters it; an utterance of “you” designates the person to whom it is addressed, an utterance of “here” designates the place at which the utterance is made, and so forth. Because indexicals shift their designation in this way, sentences containing indexicals can be used to say different things on different occasions. Suppose you say to me, “You are wrong and I am right about reference,” and I reply with the same sentence. We have used the same sentence, with the same meaning, but said quite different and incompatible things

The topic of this essay is “the slingshot,” a short argument that purports to show that sentences1 designate (stand for, refer to) truth values. Versions of this argument have been used by Frege 2, Church 3, Quine4 and Davidson5; thus it is historically important, even if it immediately strikes one as fishy. The argument turns on two principles, which I call substitution and redistribution. In “Semantic Innocence and Uncompromising Situations,”6 Jon Barwise and I rejected both principles, as part of our attempt..