Single Idea 18107

[catalogued under 4. Formal Logic / F. Set Theory ST / 3. Types of Set / a. Types of set]

Full Idea

A 'proper class' cannot be a member of anything, neither of a set nor of another proper class.

Gist of Idea

A 'proper class' cannot be a member of anything

Source

David Bostock (Philosophy of Mathematics [2009], 5.4)

Book Reference

Bostock,David: 'Philosophy of Mathematics: An Introduction' [Wiley-Blackwell 2009], p.151