ABSTRACT
For Frege ‘concept’ is a logical term, contrasted with OBJECT. ‘A concept is the referent of a predicate’, while only an object can be the referent of a subject. Concepts can indeed he talked about, but only rather obliquely, in the way that ‘There is at least one square root of four’ talks about the concept square root of four. In ‘Arkle is a horse’ ‘Arkle’ introduces an object while ‘is a horse’ introduces a concept. Concepts are thus somehow incomplete: ‘Arkle’ can stand by itself, as a name, in a way that ‘is a horse’ cannot. Frege expressed this by calling objects saturated and concepts unsaturated (but cf. Dummett, pp. 31-3). Frege in fact defined a concept as ‘a FUNCTION whose value [see VARIABLE] is always a TRUTH-VALUE’. Since what is referred to by a subjectterm is automatically an object, Frege concluded paradoxically that ‘the concept horse is not a concept’ since we are referring to it. For Peacocke concepts are modes of presentation of properties.
