Metamath Proof Explorer


Theorem ralseu1d

Description: Deduction rule: Given "all some one" applied to a class, you can extract the "for all" part. (Contributed by David A. Wheeler, 21-Jul-2026)

Ref Expression
Hypothesis ralseu1d.1
|- ( ph -> AE! x e. A ( ps -> ch ) )
Assertion ralseu1d
|- ( ph -> A. x e. A ( ps -> ch ) )

Proof

Step Hyp Ref Expression
1 ralseu1d.1
 |-  ( ph -> AE! x e. A ( ps -> ch ) )
2 df-ralseu
 |-  ( AE! x e. A ( ps -> ch ) <-> ( A. x e. A ( ps -> ch ) /\ E! x e. A ps ) )
3 1 2 sylib
 |-  ( ph -> ( A. x e. A ( ps -> ch ) /\ E! x e. A ps ) )
4 3 simpld
 |-  ( ph -> A. x e. A ( ps -> ch ) )