Metamath Proof Explorer


Theorem bj-spimvwt

Description: Closed form of spimvw . See also spimt . (Contributed by BJ, 8-Nov-2021)

Ref Expression
Assertion bj-spimvwt ⊢ ∀ x x = y → φ → ψ → ∀ x φ → ψ

Proof

Step Hyp Ref Expression
1 alequexv ⊢ ∀ x x = y → φ → ψ → ∃ x φ → ψ
2 19.36v ⊢ ∃ x φ → ψ ↔ ∀ x φ → ψ
3 1 2 sylib ⊢ ∀ x x = y → φ → ψ → ∀ x φ → ψ