Metamath Proof Explorer


Theorem bnj937

Description: First-order logic and set theory. (Contributed by Jonathan Ben-Naim, 3-Jun-2011) (New usage is discouraged.)

Ref Expression
Hypothesis bnj937.1
|- ( ph -> E. x ps )
Assertion bnj937
|- ( ph -> ps )

Proof

Step Hyp Ref Expression
1 bnj937.1
 |-  ( ph -> E. x ps )
2 19.9v
 |-  ( E. x ps <-> ps )
3 1 2 sylib
 |-  ( ph -> ps )