more from Volker Halbach

### Single Idea 16312

#### [catalogued under 6. Mathematics / B. Foundations for Mathematics / 5. Mathematics as Set Theory / a. Mathematics is set theory]

Full Idea

For the reduction of Peano Arithmetic to ZF set theory, usually the set of finite von Neumann ordinals is used to represent the non-negative integers.

Gist of Idea

To reduce PA to ZF, we represent the non-negative integers with von Neumann ordinals

Source

Volker Halbach (Axiomatic Theories of Truth [2011], 6)

Book Reference

Halbach,Volker: 'Axiomatic Theories of Truth' [CUP 2011], p.41

A Reaction

Halbach makes it clear that this is just one mode of reduction, relative interpretability.

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