Search All of the Math Forum:
Views expressed in these public forums are not endorsed by
Drexel University or The Math Forum.



Re: Question related to "Foundations of Mathematics"
Posted:
Apr 2, 2012 1:00 PM


On Mar 10, 10:20Â am, mv_Cristi <mv_cri...@yahoo.com> wrote: > I made up it, I didn't find anything about it, so I need help. > > The question is: How do different set theories handle the following > definition? > > U := {x : (x belongs_to A) and ( Not(A is_included_in Powerset( > EmptySet)) )} > > If possible in the set theory, require (A is_set). But it doesn't > really matter. > > The set U is interesting for some reasons. > > The answer will help me a lot in my PhD. research. > > Thank You.
Hello , U = A unless A is either emp (the empty set) or the set {empt} whose only element is emp in which case U=emp . What do you wish to know ? smn



