more from Gottlob Frege

### Single Idea 9834

#### [catalogued under 4. Formal Logic / F. Set Theory ST / 5. Conceptions of Set / c. Logical sets]

Full Idea

A class is, for Frege, the extension of a concept.

Gist of Idea

A class is, for Frege, the extension of a concept

Source

report of Gottlob Frege (Grundlagen der Arithmetik (Foundations) [1884]) by Michael Dummett - Frege philosophy of mathematics Ch.8

Book Reference

Dummett,Michael: 'Frege: philosophy of mathematics' [Duckworth 1991], p.91

A Reaction

This simple idea was the source of all his troubles, because there are concepts which can't have an extension, because of contradiction. ...And yet all intuition says Frege is right..