Relativism and Contextualism
Suppose we are relativists about moral judgements. That is, we believe that, for example,
"One should not engage in premarital sex"
may be truely asserted by somebody iff according to his moral code (or the moral code of his community, or something like that) one should not engage in premarital sex. The important part here is of course "truely". Noone denies that if you believe that one should not engage in premarital sex then if asked about it, you should say so. That's not relativism. Relativism as I understand it holds that what you said then would be true.
So relativism is a kind of contextualism: Different utterances of a moral judgement can differ in truth value, depending on where and when and by whom the utterance is produced. A nice and simple theory of context-dependence is that all context-dependent sentences contain hidden indexicals, or are at least in some sense equivalent with sentences that contain explicit indexicals: "One should not engage in premarital sex" is equivalent with "According to my moral code, one should not engage in premarital sex". This is nice and simple because as relativists we believe that an utterance of "One should etc." in a context C is true iff according to the moral code relevant in C -- nameley, the moral code of the speaker --, one should etc. And these are obviously the very same truth conditions as those for "According to my moral code one should etc".
Unfortunately, there are a number of well-known problems. One is that on the hidden-indexical account of relativism, moral judgements are about the speaker's moral code, whereas in fact they are about premarital sex (or whatever is at issue). I wouldn't rely too much on those aboutness intuitions. Clearly, a statement can be about several different topics at once. Whether an utterance of "There is a glacier on Mt Baker" is true depends on when the utterance is made (because the glacier disappeared in the last 20 years). It doesn't follow that such an utterance is only about the present time, and not also about Mt Baker.
A better objection is that on the hidden-indexical account, there can never be real disagreement about moral judgements: When you say that premarital sex is wrong, and I say it's fine, we don't disagree if you only meant that according to your standards it's wrong. The problem gets less pressing if we take not only the speaker's moral code to be relevant but also the code of his community, or of his audience. But this doesn't make the problem go away. When you belong to a community where everyone believes that premarital sex is wrong and you say so to members of your community, I still disagree with what you said. In my view, this indeed refutes the hidden-indexical account of moral relativism. But it does so only because it refutes moral relativism in general. Remember, moral relativism (as I introduced it) holds that if uttered in a suitable context where the relevant people have the relevant moral attitudes your judgement is true. But it's false wherever it is (sincerely and literally) uttered.
However, we must be careful here again not to rely too much on intuitions about aboutness, or "what is said". There is no need to think that whenever you say S and I say "no" there is some proposition P expressed by S ("what is said") that you believe and I disbelieve. Example: When you say "I believe there is a glacier on Mt Baker" and I say "no, that glacier has melted", we disagree, but we don't disagree about whether you believe that there is a glacier on Mt Baker, which is what you said.
Another example: When you say "vegemite is delicious" and I say "no, it's awful", we disagree, but it's not clear to me whether we disagree about what you said. I'm a bit uncertain about the truth conditions of those sentences. On the one hand, I think there is a sense in which an utterance of "vegemite tastes delicious" is true iff the speaker likes the taste of vegemite. In this sense, I don't disagree with what you said. On the other hand, if you said that you like the taste of vegemite, why did I reply "no, it's awful"? That sounds quite inappropriate. I should have replied "oh, well, I don't like it".
This time, I blame the hidden-indexical theory. I don't blame it for being false but for being misleading. For it suggests that the relevant sentences play approximately the same role in communication as the respective indexical sentences. But for some reason that I don't quite understand, they do not -- even though they have the same truth conditions.
This kind of phenomenon is common to many context-dependent sentences without indexicals. Suppose you and I are in two different cities 100 km away from each other. We talk on the telephone.
You: You shouldn't take the bike. Aren't there any busses that can take you there? I've just been out and it is really very cold and stormy.
I: No, it's not. Here the rain has stopped an hour ago.
Assuming that at your place it is really very cold and stormy, it seems to me that your utterance of "it is really very cold and stormy" was true. And I had no reason to doubt that. Then why did I reply "no, it's not"?
Another context where context-dependent sentences without indexicals don't behave like context-dependent sentences with indexicals are statements about utterances of those sentences. In the above context I could truely say:
1) You truely said "it's very cold and stormy" even though it's not very cold and stormy.
But that sounds slightly odd. It doesn't sound odd to say
2) You truely said "it's very cold and stormy here" even though it's not very cold and stormy here.
How odd this kind of statement sounds depends on how obvious it is that the truth value of the quoted utterance depends on aspects of context that might have been different from what they are now. It is very obvious when indexicals are present. It is also fairly obvious for statements about the weather or taste. That's why (1) and
3) You truely said "vegemite is delicious" even though vegemite isn't delicious
don't sound quite as odd as, for instance,
4) You truely said "there is a glacier on Mt Baker" even though there is no glacier on Mt Baker
(true if your original utterance was in 1970),
5) You truely said "it is impossible that something travels faster than light" even though it is possible that something travels faster than light.
(true if you originally talked about nomological possibility whereas I talk about metaphysical possibility),
6) You truely said "all swans are white" even though not all swans are white
(true if you originally talked about a certain subclass of all swans),
7) You truely said "France is hexagonal" even though France is not hexagonal
(true if the contextual standards of precision were much lower when you made your utterance than they are now)
8) You truely said "Fred knows that he sees a zebra" even though Fred doesn't know that he sees a zebra
(true if you said it in an ordinary context and I say it in a discussion about whether zebras can be easily distinguished from disguised mules).