more from Stephen Read

### Single Idea 10997

#### [catalogued under 6. Mathematics / B. Foundations for Mathematics / 5. Definitions of Number / g. Von Neumann numbers]

Full Idea

The Von Neumann numbers have a structural isomorphism to the natural numbers - each number is the set of all its predecessors, so 2 is the set of 0 and 1. This helps proofs, but is unacceptable. 2 is not a set with two members, or a member of 3.

Gist of Idea

Von Neumann numbers are helpful, but don't correctly describe numbers

Source

Stephen Read (Thinking About Logic [1995], Ch.4)

Book Reference

Read,Stephen: 'Thinking About Logic' [OUP 1995], p.106