Theorem cbvalivw 1921

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.)

Hypothesis

Ref	Expression
cbvalivw.1	⊢ (𝑥 = 𝑦 → (𝜑 → 𝜓))

Assertion

Ref	Expression
cbvalivw	⊢ (∀𝑥𝜑 → ∀𝑦𝜓)

Distinct variable groups:   𝑥,𝑦   𝜓,𝑥   𝜑,𝑦

Allowed substitution hints:   𝜑(𝑥)   𝜓(𝑦)

Proof of Theorem cbvalivw

Step	Hyp	Ref	Expression
1		cbvalivw.1	. . 3 ⊢ (𝑥 = 𝑦 → (𝜑 → 𝜓))
2	1	spimvw 1914	. 2 ⊢ (∀𝑥𝜑 → 𝜓)
3	2	alrimiv 1842	1 ⊢ (∀𝑥𝜑 → ∀𝑦𝜓)

Syntax hints:   → wi 4  ∀wal 1473

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1713  ax-4 1728  ax-5 1827  ax-6 1875

This theorem depends on definitions:  df-bi 196  df-ex 1696

This theorem is referenced by:  alcomiw  1958  cbvaev  1966  axc11next  37629