Jerry Katz, who may well merit the label ‘founder of philosophy of linguistics’, bequeathed us a taxonomy of views about the subject matter of linguistics:
- Physicalism: Linguistics is about physical things and happenings. Languages belong in the same ontological family as rocks, hail storms, and sets of such like.
- Mentalism: Linguistics is about mental things and happenings. Languages belong in the same ontological family as hallucinations and tickles.
- Platonism: Linguistics is about abstract objects. Languages belong in the same ontological family as numbers and systems of logic.
Katz thought these were mutually exclusive. He might have thought them exhaustive. But I would have added a fourth option:
4. The Social-Norms View: Linguistics is about social practices. Languages belong in the same ontological category as games, religions, dances, etc.
PLURALISM about the metaphysics of linguistics is the view that all four of these are, to some extent, correct. They emphatically are not mutually exclusive. (I don’t think they’re exhaustive either.) To use my long-standing slogan, a language is by equal measures an abstract system of symbols which we humans know and use.