Theorem axc16

Description: Proof of older axiom ax-c16 . (Contributed by NM, 8-Nov-2006) (Revised by NM, 22-Sep-2017)

	Ref	Expression
Assertion	axc16	⊢ ( ∀ 𝑥 𝑥 = 𝑦 → ( 𝜑 → ∀ 𝑥 𝜑 ) )

Proof

Step	Hyp	Ref	Expression
1		axc16g	⊢ ( ∀ 𝑥 𝑥 = 𝑦 → ( 𝜑 → ∀ 𝑥 𝜑 ) )