Abstract

Semantic theory has been used for many different philosophical purposes. This thesis investigates two such uses of semantic theory. The first is the use of semantic theory in providing a justification for a formal theory. The second is the use of semantic theory in yielding an account of understanding. ;The first paper is "Truth and Metatheory in Frege". In this paper, it is contended, against much recent work in Frege interpretation, that Frege should be credited with the first semi-rigourous formulation of a semantic theory. In so doing, it attempts to show that many of the arguments which purport to establish that Frege could not have engaged in semantic theorizing suffer from two kinds of misconceptions. The first misconception involves the notion of truth which a philosopher must accept in order to engage in such theorizing. The second misconception involves the sort of justification which these arguments assume a semantic theory attempts to provide. ;The second paper is "Frege's Thesis". For each primitive expression in a language, two questions may be asked. The first is: what is it in virtue of which that expression has the semantic value it does? The second is: what is it in virtue of which a speaker counts as understanding that expression? Frege's Thesis states that one answer can be given to both of these questions: that the account of what it is in virtue of which a speaker understands an expression can also serve as the account of why that expression has the semantic value it does. In this paper, Frege's Thesis is defended. First, it is argued that some objections against it result from a confusion between semantics and metasemantics. Second, the Thesis is defended against traditional objections from Kripke and Putnam. ;The third paper is "Rigidity and Content". According to much recent philosophy of language, if two utterances differ in modal semantic value, then they must express different things. In this paper, it is argued that this view is false. In particular, it is argued that the notion of content which results from this consensus is incompatible with fundamental philosophical principles relating content to use