IlyaShpitser comments on Standard and Nonstandard Numbers - Less Wrong

31 Post author: Eliezer_Yudkowsky 20 December 2012 03:23AM

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Comment author: IlyaShpitser 25 December 2012 04:28:28AM 1 point [-]

I think whether naturals plus one non-standard integer line is a model of Peano's axioms for the successor only (no addition/multiplication) depends on whether we use second order or first order logic to express induction. (No in second order formulation due to Dedekind's result, yes for any first order formulation).