Talk:Gödel's completeness theorem
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Shouldn't the redirect be the other way around ? User:TraxPlayer
[edit] Equivalence to ultrafilter lemma
When you want to claim two theorems of ZFC are equivalent, you need to specify what weaker theory they are equivalent over. Every pair of theorems ZFC is (trivially) provably equivalent over ZFC. So for example, the ultrafilter lemma and the statement 1 + 1 = 2 are equivalent over ZFC.
Also, could somebody give me (in the discussion) a quick sketch of that proof? I don't see it offhand. I suppose that you need something to do the Henkin construction; is that it?