My own view on the metaphysics of linguistics is that natural languages have, by equal measures, concrete physical, mental, abstract and social facets. The same holds for words and sentences: they are metaphysical hybrids. There seems, however, to be an insurmountable obstacle to this Pluralist answer, namely that we are faced with four mutually exclusive ontological categories. Nothing can be inside the mind, yet outside it. Nothing can be abstract, hence lacking spatio-temporal location, yet be physical. No physical thing is inherently normed. And so on. Hence Linguistics simply cannot be about such “things”. Much of this section will be devoted to addressing this quandary.
There is an obvious rebuttal on behalf of my Pluralism, namely that “the linguistic” is a complex phenomenon with parts that belong to distinct ontological categories. This shouldn’t surprise, since even “the mathematical” is like this: two wholly physical dogs, plus two others, yields four wholly physical dogs; and there certainly is the mental operation of multiplying 26 by 84, the mental state of thinking about the square root of seven, etc. Similarly, goes the idea, there are the physical parts of “the linguistic” (e.g., the tokens and the vocal tract), the mental parts (e.g., the mental representation of the rules), the abstract parts (e.g., the types and sets of worlds), etc.
This quick and dirty rebuttal, however, misses something very important: the interdependence of the aspects in the case of natural languages. To introduce a slogan I have used elsewhere, a language is a system of symbols which we know and use (Stainton 1996). This doesn’t merely mean: there is the abstract system; I mentally represent it; many others represent roughly the same one; this shared knowledge provides a bridge between the abstract side and the physical (e.g., we use this knowledge of types to create plenty of tokens.) This cannot be the whole story because the nature of the abstract system is profoundly shaped by the minds and concrete circumstances of the users: a natural language has the properties it does, causally and constitutively, because of human mental states and activities, the spatiotemporal properties of our bodies, and our physical/social environment. (E.g., it is hard to even make sense of the idea of a phonetic feature, or an allophone, in complete abstraction from minds and bodies of human speakers. But without such things, there are no natural language expressions.) Put epistemologically, the point is that one cannot understand either the essence of natural languages or their nomic relations without studying how they are learned, stored, processed, deployed in speech, reading, etc. In sharp contrast with “the mathematical”, one cannot first catalogue the properties of an abstract linguistic system and its elements, and then (if one is so disposed) consider our knowledge and use thereof.
A better rebuttal, and the one I will pursue in a later post, is that the worry rests on an equivocation on three key terms – i.e., ‘physical’, ‘mental’ and ‘abstract’. If one focuses on the wrong senses of these words, the Pluralist view looks inconsistent.