But I could easily claim that the way strings like “me” and “here” change their meanings depending on context just shows that we do not always speak the same language.
Then you are employing the word “language” in an idiosyncratic, confusing, and, in my opinion, not very useful way. Note that we also switch languages depending on where we are (“here”) and, in fact, continuously all the time (“now”). Good luck building a theory on that.
You might want to look up the notion of a Kaplanian character, which is precisely the intermediate level that you’re suggesting. A character is a function from contexts of utterance to propositions, and the (language-relative) meaning of a sentence is such a character, so, as you say, you could think of a language as a relation between strings and characters (not a function, because of ambiguity). In that picture, an expression is called “indexical” when its character is not a constant function.
Why we should care about that? Because it’s useful in explaining why we understand each other despite the fact that we don’t express the same propositions with one and the same sentence all the time, I suppose.
So the claim that “wrong” is indexical is certainly meaningful and non-trivial. Whether it’s correct is another matter. (I think it isn’t.)
Then you are employing the word “language” in an idiosyncratic, confusing, and, in my opinion, not very useful way. Note that we also switch languages depending on where we are (“here”) and, in fact, continuously all the time (“now”). Good luck building a theory on that.
You might want to look up the notion of a Kaplanian character, which is precisely the intermediate level that you’re suggesting. A character is a function from contexts of utterance to propositions, and the (language-relative) meaning of a sentence is such a character, so, as you say, you could think of a language as a relation between strings and characters (not a function, because of ambiguity). In that picture, an expression is called “indexical” when its character is not a constant function.
Why we should care about that? Because it’s useful in explaining why we understand each other despite the fact that we don’t express the same propositions with one and the same sentence all the time, I suppose.
So the claim that “wrong” is indexical is certainly meaningful and non-trivial. Whether it’s correct is another matter. (I think it isn’t.)