Single Idea 23445

[catalogued under 4. Formal Logic / F. Set Theory ST / 5. Conceptions of Set / d. Naïve logical sets]

Full Idea

Naïve set theory is based on the principles that any formula defines a set, and that coextensive sets are identical.

Gist of Idea

Naïve set theory says any formula defines a set, and coextensive sets are identical

Source

Øystein Linnebo (Philosophy of Mathematics [2017], 4.2)

Book Reference

Linnebo,Øystein: 'Philosophy of Mathematics' [Princeton 2017], p.62


A Reaction

The second principle is a standard axiom of ZFC. The first principle causes the trouble.