Metamath Proof Explorer


Theorem pwuninel2

Description: Direct proof of pwuninel avoiding functions and thus several ZF axioms. (Contributed by Stefan O'Rear, 22-Feb-2015)

Ref Expression
Assertion pwuninel2 A V ¬ 𝒫 A A

Proof

Step Hyp Ref Expression
1 pwnss A V ¬ 𝒫 A A
2 elssuni 𝒫 A A 𝒫 A A
3 1 2 nsyl A V ¬ 𝒫 A A