Single Idea 8721

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

Full Idea

An 'impredicative' definition is one that uses the terms being defined in order to give the definition; in some way the definition is then circular.

Gist of Idea

An 'impredicative' definition seems circular, because it uses the term being defined


Michèle Friend (Introducing the Philosophy of Mathematics [2007], Glossary)

Book Reference

Friend,Michèle: 'Introducing the Philosophy of Mathematics' [Acumen 2007], p.172

A Reaction

There has been a big controversy in the philosophy of mathematics over these. Shapiro gives the definition of 'village idiot' (which probably mentions 'village') as an example.