Metamath Proof Explorer


Theorem naev2

Description: Generalization of hbnaev . (Contributed by Wolf Lammen, 9-Apr-2021)

Ref Expression
Assertion naev2 ⊢ ¬ ∀ x x = y → ∀ z ¬ ∀ t t = u

Proof

Step Hyp Ref Expression
1 naev ⊢ ¬ ∀ x x = y → ¬ ∀ v v = w
2 ax-5 ⊢ ¬ ∀ v v = w → ∀ z ¬ ∀ v v = w
3 naev ⊢ ¬ ∀ v v = w → ¬ ∀ t t = u
4 3 alimi ⊢ ∀ z ¬ ∀ v v = w → ∀ z ¬ ∀ t t = u
5 1 2 4 3syl ⊢ ¬ ∀ x x = y → ∀ z ¬ ∀ t t = u