Metamath Proof Explorer


Theorem spimev

Description: Distinct-variable version of spime . (Contributed by NM, 10-Jan-1993) Usage of this theorem is discouraged because it depends on ax-13 . Use spimevw instead. (New usage is discouraged.)

Ref Expression
Hypothesis spimev.1 ⊢ x = y → φ → ψ
Assertion spimev ⊢ φ → ∃ x ψ

Proof

Step Hyp Ref Expression
1 spimev.1 ⊢ x = y → φ → ψ
2 nfv ⊢ Ⅎ x φ
3 2 1 spime ⊢ φ → ∃ x ψ