Theorem cbvalivw

Description: Change bound variable. Uses only Tarski's FOL axiom schemes. Part of Lemma 7 of KalishMontague p. 86. (Contributed by NM, 9-Apr-2017)

	Ref	Expression
Hypothesis	cbvalivw.1	|- ( x = y -> ( ph -> ps ) )
Assertion	cbvalivw	|- ( A. x ph -> A. y ps )

Proof

Step	Hyp	Ref	Expression
1		cbvalivw.1	|- ( x = y -> ( ph -> ps ) )
2	1	spimvw	|- ( A. x ph -> ps )
3	2	alrimiv	|- ( A. x ph -> A. y ps )