The semantical and the epistemological
Concerning Dummett’s criticism of Davidson’s semantics (cf., ‘What is a theory of meaning? (II)’ ). First step: a semantic theory is (also) a theory of competence, i.e., of the ability to use the language with its semantics. That much is unproblematic from a Davidsonian perspective, it is what Davidson starts out with (cf., the opening paragraphs of ‘Truth and meaning, and ‘Radical interpretation’). Second step: adding the requirement that this ‘knowledge of language’ must be manifested (or, at least, manifestable). As such that does not seem to be objectionable from a Davidsonian perspective, the crux of the matter is what will count as manifestation of semantic knowledge.
Next, Dummett seems to make two moves. First he constructs semantic knowledge as the ability to observe that truth conditions obtain, and then, correctly of course, notes that taken in a more or less `literal’ way, this is problematic for sentences that have truth conditions that involve counterfactual or past situations or infinite domains. One reply to that could be that observation of truth conditions being fulfilled is not a very representative case anyway, and that it seems much more natural to construe manifestation of knowledge of truth conditions in terms of having knowledge of ways of ascertaining that truth conditions hold. (So, with regard to the past, a basic knowledge of historical methods; with regard to infinite domains, the concept of a proof by induction; etc.) This is not something Dummett spells out, but he seems to tie in with this, since the next move he makes is to suggest that verification actually is what we are after: the ability to manifest semantic knowledge is the ability to verify sentences (statements). That is a crucial move, since now the semantic and the epistemological are intimately tied: semantic competence, viz., the ability to use language correctly, has now been identified with what at first sight seems to be an epistemological `competence’, viz., the ability to verify a statement (always ‘in principle’, of course).
Here, I guess, Davidson would object. In ‘A coherence theory of truth and knowledge’ he makes an effort to carefully dissociate the semantic and the epistemological, and in a criticism of his ideas that effort cannot simply be neglected. It must be shown defective before this further step can be taken. For Davidson verification, as a particular form of justification, belongs to the coherence notion of truth, which is not to be mistaken for the `mild’ correspondence notion that plays a role in semantics and semantic competence.
The difference between Dummett’s and Davidson’s position is a substantial one. By separating semantics and epistemology Davidson makes room for the possibility that we might be able to understand statements that are epistemologically unassailable, whereas in Dummett’s approach this becomes impossible. Mathematics provides an example: Dummett’s view on meaning forces him to adopt a constructivistic approach to mathematics, whereas for Davidson such an approach would need additional arguments that do not hinge on the semantics of mathematical statements.
What is the right approach is not obvious in any way, the point here is simply that the transition from the requirement that one be able to manifest one’s semantic knowledge to the requirement that one have a method of verification is one that stands in need of argumentation and that part of that argumentation is essentially non-semantic.
date: fall 2001