Wolfgang Schwarz

An Argument For Type-A Materialism

Some strings of symbols and noises and brain states have semantic properties. What makes it the case that a particular string or noise or state has the semantic properties that it has? One possible answer is that nothing does: semantic properties are fundamental, primitive and inexplicable. That's incredible. Not only because semantic properties just don't feel fundamental, as Fodor pointed out long ago. Much worse, it would make little sense of our use of semantic vocabulary: we believe that our expression "the moon" denotes that heavenly body up there; but how do we know? Maybe it really denotes the largest red thing in Alaska, or Gottlob Frege, or nothing at all. If reference is fundamental, facts about how "the moon" is used, how it got introduced, what conceptual role it plays, in what kinds of causal or counterfactual relations it stands to other things, how people verify statements containing it, what degree of naturalness various candidate referents have, etc. must all be considered irrelevant. On this view, there is a possible world where all these facts about use etc. obtain, but where "the moon" denotes Gottlob Frege. Obviously that's silly. Semantic properties are clearly determined by facts about use, baptising, causal chains, naturalness, etc. (In so far as they are determined at all, that is. No doubt sometimes the facts about use etc. are insufficient to settle whether a string or noise or state has semantic property A or B. But then it really is indeterminate which of the properties it has.)

Now consider words (or concepts) for phenomenal experiences like "the distinctive quality of my current red-experience". They, too, have semantic properties. Let's assume for instance that "the distinctive quality of my current red-experience" has reference, and let's call its referent "the red-quale". What makes it the case that the red quale is the referent of "the distinctive quality of my current red-experiences"? Well, again, something like use and causal and counterfactual connections, acts of baptising, naturalness, etc. Not magic. Not nothing at all. That is, once you know all facts about use etc., you know what the referent is. At least you would know if you were sufficiently clever, which maybe none of us is.

Next, suppose that, as we non-eliminative materialists hold, the referent is a brain state, or a property of brain states. Given enough physical and biological information you can certainly find out whether somebody is in such a brain state or not. Taken together, it follows that from a sufficiently rich description of various physical and biological facts, facts about use, causal connections, counterfactuals, naturalness, etc., you can in principle derive a priori whether somebody experiences the distinctive quality of my current red-experience.

This is not quite type-A materialism. But almost. Type-A materialism requires that phenomenal truths be a priori deriveable from physical truths. We get that if we assume that the "facts about use, causal connections, counterfactuals, naturalness, etc." will all count as physical facts. Since the list ends with "etc." this is not entirely trivial. But firstly, there are reasons to assume that the list is already long enough, that in fact a much shorter list will do. For instance, I personally believe that for intentional states, facts about observable behaviour and naturalness alone go a long way to determining the states' semantic properties. On other accounts, facts about causal or counterfactual connections in principle suffice. So there is little reason to believe that something completely new and non-physical must be added to the list to get a working semantics. (I assume that facts about counterfactuals and naturalness count as "physical". If you disagree, we have different conceptions of "materialism". I'm interested in defending materialism on my conception, not on yours.) Secondly, rescuing type-B materialism by supposing that phenomenal concepts are essential in semantics isn't much better than the mad view of primitive semantics outlined above: the point there was not merely that the semantic facts are somehow necessitated by other facts, as mental facts are necessitated by physical facts on the type-B materialist position. The point was that this necessitation is a conceptual matter. It is not only impossible but really inconceivable and conceptually incoherent that a term could be used etc. just like "the moon" and yet denote Gottlob Frege.

So type-B materialism not only leads to a muddled view of modality; it also leads to an altogether unacceptable view of semantics. I believe a similar argument shows that dualism has unwelcome, albeit not quite unacceptable, implications for semantics. More on that later, I hope.