ABSTRACT

Frege begins with a two-pronged attack on naïve semantics. The first prong concerns co-referential singular terms. For example, since the Morning Star = the Evening Star, the meaning of ‘the Morning Star’ = the meaning of ‘the Evening Star’, according to the naïve theory. But that conflicts with the evident fact that the two sentences ‘The Morning Star is a planet’ and ‘The Evening Star is a planet’ do not mean the same. The second prong of the attack concerns non-referring singular terms, such as ‘The Loch Ness Monster’. According to naïve theory, its lacking reference entails that it lacks meaning; but this is evidently wrong. Frege responds to difficulties by postulating that each meaningful expression expresses a sense, which is a rule for determining the referent of the expression, if it has one. The distinction is drawn across the board: all expressions express senses. Repercussions and clarifications of the doctrine include Frege’s view of the propositional attitudes, and of singular negative existentials. Frege argues that there is no coherent alternative to the objectivity of sense; propositions are not in anyone’s mind, but are public abstract entities. The chapter concludes with Frege’s famous discussions of the concept horse problem and the context principle.