Theorem cbvralsvw 3292

Description: Change bound variable by using a substitution. Version of cbvralsv 3342 with a disjoint variable condition, which does not require ax-13 2371. (Contributed by NM, 20-Nov-2005.) Avoid ax-13 2371. (Revised by GG, 10-Jan-2024.) (Proof shortened by Wolf Lammen, 8-Mar-2025.) Avoid ax-10 2142, ax-12 2178. (Revised by SN, 21-Aug-2025.)

Assertion

Ref	Expression
cbvralsvw	⊢ (∀𝑥 ∈ 𝐴 𝜑 ↔ ∀𝑦 ∈ 𝐴 [𝑦 / 𝑥]𝜑)

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

Allowed substitution hint:   𝜑(𝑥)

Proof of Theorem cbvralsvw

Step	Hyp	Ref	Expression
1		sb8v 2351	. 2 ⊢ (∀𝑥(𝑥 ∈ 𝐴 → 𝜑) ↔ ∀𝑦[𝑦 / 𝑥](𝑥 ∈ 𝐴 → 𝜑))
2		df-ral 3046	. 2 ⊢ (∀𝑥 ∈ 𝐴 𝜑 ↔ ∀𝑥(𝑥 ∈ 𝐴 → 𝜑))
3		df-ral 3046	. . 3 ⊢ (∀𝑦 ∈ 𝐴 [𝑦 / 𝑥]𝜑 ↔ ∀𝑦(𝑦 ∈ 𝐴 → [𝑦 / 𝑥]𝜑))
4		eleq1w 2812	. . . . . . 7 ⊢ (𝑥 = 𝑦 → (𝑥 ∈ 𝐴 ↔ 𝑦 ∈ 𝐴))
5	4	imbi1d 341	. . . . . 6 ⊢ (𝑥 = 𝑦 → ((𝑥 ∈ 𝐴 → 𝜑) ↔ (𝑦 ∈ 𝐴 → 𝜑)))
6	5	sbbiiev 2093	. . . . 5 ⊢ ([𝑦 / 𝑥](𝑥 ∈ 𝐴 → 𝜑) ↔ [𝑦 / 𝑥](𝑦 ∈ 𝐴 → 𝜑))
7		sbrimvw 2092	. . . . 5 ⊢ ([𝑦 / 𝑥](𝑦 ∈ 𝐴 → 𝜑) ↔ (𝑦 ∈ 𝐴 → [𝑦 / 𝑥]𝜑))
8	6, 7	bitr2i 276	. . . 4 ⊢ ((𝑦 ∈ 𝐴 → [𝑦 / 𝑥]𝜑) ↔ [𝑦 / 𝑥](𝑥 ∈ 𝐴 → 𝜑))
9	8	albii 1819	. . 3 ⊢ (∀𝑦(𝑦 ∈ 𝐴 → [𝑦 / 𝑥]𝜑) ↔ ∀𝑦[𝑦 / 𝑥](𝑥 ∈ 𝐴 → 𝜑))
10	3, 9	bitri 275	. 2 ⊢ (∀𝑦 ∈ 𝐴 [𝑦 / 𝑥]𝜑 ↔ ∀𝑦[𝑦 / 𝑥](𝑥 ∈ 𝐴 → 𝜑))
11	1, 2, 10	3bitr4i 303	1 ⊢ (∀𝑥 ∈ 𝐴 𝜑 ↔ ∀𝑦 ∈ 𝐴 [𝑦 / 𝑥]𝜑)

Syntax hints:   → wi 4   ↔ wb 206  ∀wal 1538  [wsb 2065   ∈ wcel 2109  ∀wral 3045

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1795  ax-4 1809  ax-5 1910  ax-6 1967  ax-7 2008  ax-8 2111  ax-11 2158

This theorem depends on definitions:  df-bi 207  df-an 396  df-ex 1780  df-sb 2066  df-clel 2804  df-ral 3046

This theorem is referenced by:  sbralieALT  3329  rspsbc  3845  ralxpf  5813  tfinds  7839  tfindes  7842  nn0min  32752