Metamath Proof Explorer


Theorem bj-axc11v

Description: Version of axc11 with a disjoint variable condition, which does not require ax-13 nor ax-10 . Remark: the following theorems ( hbae , nfae , hbnae , nfnae , hbnaes ) would need to be totally unbundled to be proved without ax-13 , hence would be simple consequences of ax-5 or nfv . (Contributed by BJ, 31-May-2019) (Proof modification is discouraged.)

Ref Expression
Assertion bj-axc11v ⊢ ∀ x x = y → ∀ x φ → ∀ y φ

Proof

Step Hyp Ref Expression
1 axc11rv ⊢ ∀ y y = x → ∀ x φ → ∀ y φ
2 1 bj-aecomsv ⊢ ∀ x x = y → ∀ x φ → ∀ y φ