more from Volker Halbach

### Single Idea 16321

#### [catalogued under 6. Mathematics / B. Foundations for Mathematics / 3. Axioms for Number / d. Peano arithmetic]

Full Idea

Nonstandard models of Peano arithmetic are models of PA that are not isomorphic to the standard model. Their existence can be established with the compactness theorem or the adequacy theorem of first-order logic.

Gist of Idea

The compactness theorem can prove nonstandard models of PA

Source

Volker Halbach (Axiomatic Theories of Truth [2011], 8.3)

Book Reference

Halbach,Volker: 'Axiomatic Theories of Truth' [CUP 2011], p.83

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