Theorem axc4i

Description: Inference version of axc4 . (Contributed by NM, 3-Jan-1993)

	Ref	Expression
Hypothesis	axc4i.1	$$⊢\forall x\phi \to \psi$$
Assertion	axc4i	$$⊢\forall x\phi \to \forall x\psi$$

Proof

Step	Hyp	Ref	Expression
1		axc4i.1	$$⊢\forall x\phi \to \psi$$
2		nfa1	$$⊢Ⅎx\forall x\phi$$
3	2 1	alrimi	$$⊢\forall x\phi \to \forall x\psi$$