[FOM] concerning surjection from S^2 onto Pow(S)
Harvey Friedman
hmflogic at gmail.com
Fri Oct 19 00:36:57 EDT 2012
Concerning that equivalence in
http://www.cs.nyu.edu/pipermail/fom/2012-October/016716.html
When I posted that message on the FOM, I had assumed that the status
of the equivalence in ZF was known, and was expecting someone to give
me a reference.
So let me now state explicitly that although the equivalence is
obviously provable in ZFC (Replacement not needed), I do not know if
it is provable in ZF.
I expect that it is not provable in ZF.
To summarize, I expect that ZF does not prove that the following are equivalent:
1. there is a surjective map from S x S onto Pow(S).
2. S has exactly two, three, or four elements.
Harvey Friedman
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