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user21820
user21820
04:15
6
A: Prove $\langle \mathbb{N}, x \mapsto x +1, 1 \rangle$ is a Peano system without circular reasoning

user21820Actually, you cannot give a truly non-circular 'proof' that anything is a model of PA (whether first-order or second-order Peano Arithmetic). This is because there is a fundamental circularity that we cannot avoid when building mathematics. Now the post I linked to focuses on the more specific qu...


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