Online research in philosophy

Michael Dummett has long argued that we should ascribe implicit knowledge of a meaning-theory to speakers, and that the task of a theory of meaning is to tell us what such knowledge consists in. But he also sees it as a problem that how implicit knowledge is actually used, that is, how a speaker's metalinguistic knowledge of a meaning-theory issues or delivers the speaker's knowledge of meanings of utterances (the delivery problem). In this paper 1argue that Dummett's instrumental construal of implicit knowledge does not and cannot solve the delivery problem. However, I do not suggest Dummett to modify or abandon his instrumental construal; rather, I think he can dissolve the delivery problem by recognizing that knowledge of semantics for a language is not a necessary condition for mastering a language. 1 shall argue this point through Davidson's attitude towards the role of linguistic knowledge and his thesis in his (in)famous paper "A Nice Derangement of Epitaphs.".

The standard approach to what I call “proof-theoretic semantics”, which is mainly due to Dummett and Prawitz, attempts to give a semantics of proofs by defining what counts as a valid proof. After a discussion of the general aims of proof-theoretic semantics, this paper investigates in detail various notions of proof-theoretic validity and offers certain improvements of the definitions given by Prawitz. Particular emphasis is placed on the relationship between semantic validity concepts and validity concepts used in normalization theory. It is argued that these two sorts of concepts must be kept strictly apart.

.  According to John Buridan, the time for which a statement is true is underdetermined by the grammatical form of the sentence – the intention of the speaker is required. As a consequence, truth-bearers are not sentence types, nor sentence tokens plus facts of the context of utterance, but statements. Statements are also the bearers of logical relations, since the latter can only be established among entities having determined truth-conditions. This role of the intention of the speaker in the determination of what is said by an utterance is not isolated in medieval semantics.

Formal semantics is an approach to SEMANTICS1, the study of meaning, with roots in logic, the philosophy of language, and linguistics, and since the 1980’s a core area of linguistic theory. Characteristics of formal semantics to be treated in this article include the following: Formal semanticists treat meaning as mind-independent (though abstract), contrasting with the view of meanings as concepts “in the head” (see I-LANGUAGE AND E-LANGUAGE and MEANING EXTERNALISM AND INTERNALISM); formal semanticists distinguish semantics from knowledge of semantics (Lewis 1975, Cresswell 1978), which has consequences for the notion of semantic COMPETENCE. A central part of the meaning of a sentence on this approach is its TRUTH CONDITIONS, and most although not all formal semantics is model-theoretic, relating linguistic expressions to model-theoretically constructed semantic values cast in terms of truth, REFERENCE, and possible worlds. This sets formal semantics apart from approaches which view semantics as relating a sentence just to a representation on another linguistic “level” (LOGICAL FORM) or a representation in an innate LANGUAGE OF THOUGHT. The formal semanticist could accept such representations as an aspect of semantics but would insist on asking what the model-theoretic semantic interpretation of the given representationlanguage is (Lewis 1970). Formal semantics is centrally concerned with COMPOSITIONALITY at the SYNTAX-SEMANTICS INTERFACE, how the meanings of larger constituents are built up from the meanings of their parts on the basis of their syntactic structure, and with the relation between compositional SENTENCE MEANING and meaning in discourse.

Controversy has arisen of late over the claim that deflationism about truth requires that we explain meaning in terms of something other than truth-conditions. This controversy, it is argued, is due to unclarity as to whether the basic deflationary claim that a sentence and a sentence that attributes truth to it are equivalent in meaning is intended to involve the truth-predicate of the object language for which we develop an account of meaning, or is intended to involve the truth-predicate of the metalanguage in which we develop an account of meaning. The former view is compatible with the truth-conditional theory of meaning for the object language, the latter is incompatible with it. However, the former view is also trivially true; hence we should endorse the claim that any form of deflationism worth being interested in is incompatible with understanding meaning truth-conditionally.

The verification theory of meaning aims to characterise what it is for a sentence to be meaningful and also what kind of abstract object the meaning of a sentence is. A brief outline is given by Rudolph Carnap, one of the theory's most prominent defenders: If we knew what it would be for a given sentence to be found true then we would know what its meaning is. [...] thus the meaning of a sentence is in a certain sense identical with the way we determine its truth or falsehood; and a sentence has meaning only if such a determination is possible. [4: 420] In short, the verification theory of meaning claims that the meaning of a sentence is the method of its verification.

If proofs are nothing more than truth makers, then there is no force in the standard argument against classical logic (there is no guarantee that there is either a proof forA or a proof fornot A). The standard intuitionistic conception of a mathematical proof is stronger: there are epistemic constraints on proofs. But the idea that proofs must be recognizable as such by us, with our actual capacities, is incompatible with the standard intuitionistic explanations of the meanings of the logical constants. Proofs are to be recognizable in principle, not necessarily in practice, as shown in section 1. Section 2 considers unknowable propositions of the kind involved in Fitch''s paradox:p and it will never be known thatp. It is argued that the intuitionist faces a dilemma: give up strongly entrenched common sense intuitions about such unknowable propositions, or give up verificationism. The third section considers one attempt to save intuitionism while partly giving up verificationism: keep the idea that a proposition is true iff there is a proof (verification) of it, and reject the idea that proofs must be recognizable in principle. It is argued that this move will have the effect that some standard reasons against classical semantics will be effective also against intuitionism. This is the case with Dummett''s meaning theoretical argument. At the same time the basic reason for regarding proofs as more than mere truth makers is lost.

Once upon a time it was assumed that speaking literally and directly is the norm and that speaking nonliterally or indirectly is the exception. The assumption was that normally what a speaker means can be read off of the meaning of the sentence he utters, and that departures from this, if not uncommon, are at least easily distinguished from normal utterances and explainable along Gricean lines. The departures were thought to be limited to obvious cases like figurative speech and conversational implicature. However, people have come to appreciate that the meaning of a typical sentence, at least one we are at all likely to use, is impoverished, at least relative to what we are likely to mean in uttering it. In other words, what a speaker normally means in uttering a sentence, even without speaking figuratively or obliquely, is an enriched version of what could be predicted from the meaning of the sentence alone. This can be because the sentence expresses a “minimal” (or “skeletal”) proposition or even because it fails to express a complete proposition at all.1 Indeed, it is now a platitude that linguistic meaning generally underdetermines speaker meaning. That is, generally what a speaker means in uttering a sentence, even if the sentence is devoid of ambiguity, vagueness, or indexicality, goes beyond what the sentence means. The question is what to make of this Contextualist Platitude, as I’ll call it. It may be a truism, but does it require a radical revision of the older conception of the relation between what sentences mean and what speakers mean in uttering them? Does it lead to a major modification, or perhaps even outright rejection, of the semantic-pragmatic distinction? I think..

Ordinary semantic compositionality (meaning of whole determined from meanings of parts plus composition) can serve to explain how a hearer manages to assign an appropriate meaning to a new sentence. But it does not serve to explain how the speaker manages to find an appropriate sentence for expressing a new thought. For this we would need a principle of inverse compositionality, by which the expression of a complex content is determined by the expressions of it parts and the mode of composition. But this presupposes that contents have constituent structure, and this cannot be taken for granted. However, it can be proved that if a certain principle of substitutivity is valid for a particular language, then the meanings expressed by its sentences can justifiably be treated as structured. In its simplest form, this principle says that if in a complex expression a constituent is replaced by another constituent with a different meaning, the new complexhas a meaning different from the original. This principle is again inversely related to the normal compositional principle of substitutivity. The combination of ordinary and inverse compositionality is here called strong compositionality. The proof is carried out in the algebraic framework developed by Wilfrid Hodges and Dag Westerståhl.

The principle of semantic compositionality, as Jerry Fodor and Ernie Lepore have emphasized, imposes constraints on theories of meaning that it is hard to meet with psychological or epistemic accounts. Here, I argue that this general tendency is exemplified in Michael Dummett's account of meaning. On that account, the so-called manifestability requirement has the effect that the speaker who understands a sentence s must be able to tell whether or not s satisfies central semantic conditions. This requirement is not met by truth-conditional accounts of meaning. On Dummett's view, it is met by a proof conditional account: understanding amounts to knowledge of what counts as a proof of a sentence . A speaker is supposed always to be capable of deciding whether or not a given object is a proof of a given sentence she understands. This requirement comes into conflict with compositionality. If meaning is compositionally determined, then all you need for understanding a sentence is what you get from combining your understanding of the parts according to the mode of composition. But that knowledge is not always sufficient for recognizing any proof at all of a given sentence. Dummett's proof-theoretic argument to the contrary is mistaken.