The powerset of the set of all sets may or may not be the set of all sets (it depends on whether or not you accept atoms in your version of set theory). However, Cantor’s theorem shows that for any set B, the power set of B has cardinality strictly larger than B. So if B=P(B) you’ve got a problem.
The powerset of the set of all sets may or may not be the set of all sets (it depends on whether or not you accept atoms in your version of set theory). However, Cantor’s theorem shows that for any set B, the power set of B has cardinality strictly larger than B. So if B=P(B) you’ve got a problem.