Single Idea 17900

[catalogued under 4. Formal Logic / F. Set Theory ST / 4. Axioms for Sets / p. Axiom of Reducibility]

Full Idea

The Axiom of Reducibility ...had the effect of making impredicative definitions possible.

Clarification

Impredicative definitions introduce nothing new

Gist of Idea

The Axiom of Reducibility made impredicative definitions possible

Source

A.George / D.J.Velleman (Philosophies of Mathematics [2002], Ch.3)

Book Reference

George,A/Velleman D.J.: 'Philosophies of Mathematics' [Blackwell 2002], p.47