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Re: How simple Z is?
Posted:
Apr 23, 2013 11:10 PM


On Apr 24, 5:23 am, Zuhair <zaljo...@gmail.com> wrote: > PreZ is the closure of all of what is provable from the logical > axioms of first order logic and the following axioms by the rules of > inference of first order logic (Hilbert style). > > Comprehension: if phi is a formula then a set {x C A phi} exists. >
Yes.
ZFC Comprehension
A(Z) E(Y) A(X) XeY <> XeZ & phi
NST
E(Y) A(X) XeY <> phi

ZFC breaks the above biconditional.
ZFC
E(Y) A(X) XeY > phi

Change <> to > and you go from NST to ZFC.

Better still, use CBL where a WFF is TRUE XOR FALSE then NST is consistent.
Herc



