Single Idea 10779

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

Full Idea

If φ contains no bound second-order variables, the corresponding comprehension axiom is said to be 'predicative'; otherwise it is 'impredicative'.

Gist of Idea

A comprehension axiom is 'predicative' if the formula has no bound second-order variables

Source

Øystein Linnebo (Plural Quantification Exposed [2003], §1)

Book Reference

-: 'Nous' [-], p.73


A Reaction

['Predicative' roughly means that a new predicate is created, and 'impredicative' means that it just uses existing predicates]