Gottlob Frege's contributions to philosophy of language are so numerous and so fundamental that it is difficult to imagine the field without them. This article discusses Frege's apparently metaphysical doctrine that concepts are ‘unsaturated’. It argues that it is primarily a semantic thesis, an essential ingredient of Frege's conception of compositionality. It next discusses Frege's conception of truth. It argues that his seemingly puzzling doctrine that sentences denote objects, namely, truth-values, emerges from considerations about the logic of sentential connectives and the semantics of...

Gottlob Frege's contributions to philosophy of language are so numerous and so fundamental that it is difficult to imagine the field without them. This article discusses Frege's apparently metaphysical doctrine that concepts are ‘unsaturated’. It argues that it is primarily a semantic thesis, an essential ingredient of Frege's conception of compositionality. It next discusses Frege's conception of truth. It argues that his seemingly puzzling doctrine that sentences denote objects, namely, truth-values, emerges from considerations about the logic of sentential connectives and the semantics of predicates and embodies an understanding of why, as Frege sees it, logic is so intimately concerned with the notion of truth. The article then turns to Frege's notion of a thought and, more generally, the distinction between sense and reference.