Metamath Proof Explorer


Theorem bj-pm11.53a

Description: A variant of pm11.53v . One can similarly prove a variant with DV ( y , ph ) and A. y F// x ps instead of DV ( x , ps ) and A. x F// y ph . (Contributed by BJ, 7-Oct-2024)

Ref Expression
Assertion bj-pm11.53a
|- ( A. x F// y ph -> ( A. x A. y ( ph -> ps ) <-> ( E. x ph -> A. y ps ) ) )

Proof

Step Hyp Ref Expression
1 bj-nnfv
 |-  F// x A. y ps
2 bj-pm11.53vw
 |-  ( ( A. x F// y ph /\ F// x A. y ps ) -> ( A. x A. y ( ph -> ps ) <-> ( E. x ph -> A. y ps ) ) )
3 1 2 mpan2
 |-  ( A. x F// y ph -> ( A. x A. y ( ph -> ps ) <-> ( E. x ph -> A. y ps ) ) )