Single Idea 9855

[catalogued under 18. Thought / E. Abstraction / 7. Abstracta by Equivalence]

Full Idea

Like psychological abstractionism, Frege's method (which we can call 'logical abstraction') aims at isolating what is in common between the members of any equivalent sets of objects, by identifying the feature with the maximal set of such objects.

Gist of Idea

Frege's logical abstaction identifies a common feature as the maximal set of equivalent objects

Source

report of Gottlob Frege (Grundlagen der Arithmetik (Foundations) [1884]) by Michael Dummett - Frege philosophy of mathematics Ch.14

Book Reference

Dummett,Michael: 'Frege: philosophy of mathematics' [Duckworth 1991], p.167


A Reaction

[compressed] So Frege's approach to abstraction is a branch of the view that properties are sets. This view, in addition to being vulnerable to Russell's paradox, ignores the causal role of properties, making them all categorical (which is daft).