Metamath Proof Explorer


Theorem spvwOLD

Description: Obsolete version of spvw as of 20-Oct-2023. (Contributed by NM, 10-Apr-2017) (Proof shortened by Wolf Lammen, 4-Dec-2017) (Proof modification is discouraged.) (New usage is discouraged.)

Ref Expression
Assertion spvwOLD
|- ( A. x ph -> ph )

Proof

Step Hyp Ref Expression
1 19.3v
 |-  ( A. x ph <-> ph )
2 1 biimpi
 |-  ( A. x ph -> ph )