more from Bernard Linsky

Single Idea 21704

[catalogued under 2. Reason / D. Definition / 8. Impredicative Definition]

Full Idea

The ban on 'impredicative' definitions says you can't define a class in terms of a totality to which that class must be seen as belonging.

Gist of Idea

'Impredictative' definitions fix a class in terms of the greater class to which it belongs


Bernard Linsky (Russell's Metaphysical Logic [1999], 1)

Book Reference

Linsky,Bernard: 'Russell's Metaphysical Logic' [CSLI 1999], p.4

A Reaction

So that would be defining 'citizen' in terms of the community to which the citizen belongs? If you are asked to define 'community' and 'citizen' together, where do you start? But how else can it be done? Russell's Reducibility aimed to block this.

Related Idea

Idea 21705 Reducibility says any impredicative function has an appropriate predicative replacement [Linsky,B]