4 ms·
There is just one model of Dedekind's axioms up to a unique isomorphism, which is indeed the standard model. However, Gödel's incompleteness proofs do not wor
by ProfHewitt 5y ago
There is just one model of Dedekind's axioms up to a unique
isomorphism, which is indeed the standard model. However,
Gödel's incompleteness proofs do not work for Dedekind's theory
because there are uncountable axiom instances. (Dedekind's
theory is nevertheless effective because proof checking is
algorithmically decidable.)
Consequently, the first incompleteness result (inferentially
undecidable) has been proved by other means. See the
following for a proof:
https://papers.ssrn.com/abstract=3603021 https://papers.ssrn.com/abstract=3603021
The above article explains that Gödel's second
incompleteness result is false because the theory can prove
its own consistency.