Comment by cevi
8 months ago
The consistency of ZFC is (presumably) a theorem of second order PA, and ZFC is unable to prove it (unless ZFC is inconsistent).
8 months ago
The consistency of ZFC is (presumably) a theorem of second order PA, and ZFC is unable to prove it (unless ZFC is inconsistent).
Indeed yes. But in a sense within ZFC one can say what N is given the categorical nature of second order PA. Each model of ZFC will have, up to isomorphism, one model of N.