Theorem cbvreucsf 3891

Description: A more general version of cbvreuv 3407 that has no distinct variable restrictions. Changes bound variables using implicit substitution. Usage of this theorem is discouraged because it depends on ax-13 2401. (Contributed by Andrew Salmon, 13-Jul-2011.) (New usage is discouraged.)

Hypotheses

Ref	Expression
cbvralcsf.1	⊢ Ⅎ𝑦𝐴
cbvralcsf.2	⊢ Ⅎ𝑥𝐵
cbvralcsf.3	⊢ Ⅎ𝑦𝜑
cbvralcsf.4	⊢ Ⅎ𝑥𝜓
cbvralcsf.5	⊢ (𝑥 = 𝑦 → 𝐴 = 𝐵)
cbvralcsf.6	⊢ (𝑥 = 𝑦 → (𝜑 ↔ 𝜓))

Assertion

Ref	Expression
cbvreucsf	⊢ (∃!𝑥 ∈ 𝐴 𝜑 ↔ ∃!𝑦 ∈ 𝐵 𝜓)

Proof of Theorem cbvreucsf

Dummy variables 𝑣 𝑧 are mutually distinct and distinct from all other variables.

Step	Hyp	Ref	Expression
1		nfv 1947	. . . 4 ⊢ Ⅎ𝑧(𝑥 ∈ 𝐴 ∧ 𝜑)
2		nfcsb1v 3871	. . . . . 6 ⊢ Ⅎ𝑥⦋𝑧 / 𝑥⦌𝐴
3	2	nfcri 2914	. . . . 5 ⊢ Ⅎ𝑥 𝑧 ∈ ⦋𝑧 / 𝑥⦌𝐴
4		nfs1v 2193	. . . . 5 ⊢ Ⅎ𝑥[𝑧 / 𝑥]𝜑
5	3, 4	nfan 1932	. . . 4 ⊢ Ⅎ𝑥(𝑧 ∈ ⦋𝑧 / 𝑥⦌𝐴 ∧ [𝑧 / 𝑥]𝜑)
6		id 23	. . . . . 6 ⊢ (𝑥 = 𝑧 → 𝑥 = 𝑧)
7		csbeq1a 3861	. . . . . 6 ⊢ (𝑥 = 𝑧 → 𝐴 = ⦋𝑧 / 𝑥⦌𝐴)
8	6, 7	eleq12d 2854	. . . . 5 ⊢ (𝑥 = 𝑧 → (𝑥 ∈ 𝐴 ↔ 𝑧 ∈ ⦋𝑧 / 𝑥⦌𝐴))
9		sbequ12 2286	. . . . 5 ⊢ (𝑥 = 𝑧 → (𝜑 ↔ [𝑧 / 𝑥]𝜑))
10	8, 9	anbi12d 644	. . . 4 ⊢ (𝑥 = 𝑧 → ((𝑥 ∈ 𝐴 ∧ 𝜑) ↔ (𝑧 ∈ ⦋𝑧 / 𝑥⦌𝐴 ∧ [𝑧 / 𝑥]𝜑)))
11	1, 5, 10	cbveu 2632	. . 3 ⊢ (∃!𝑥(𝑥 ∈ 𝐴 ∧ 𝜑) ↔ ∃!𝑧(𝑧 ∈ ⦋𝑧 / 𝑥⦌𝐴 ∧ [𝑧 / 𝑥]𝜑))
12		nfcv 2922	. . . . . . 7 ⊢ Ⅎ𝑦𝑧
13		cbvralcsf.1	. . . . . . 7 ⊢ Ⅎ𝑦𝐴
14	12, 13	nfcsb 3874	. . . . . 6 ⊢ Ⅎ𝑦⦋𝑧 / 𝑥⦌𝐴
15	14	nfcri 2914	. . . . 5 ⊢ Ⅎ𝑦 𝑧 ∈ ⦋𝑧 / 𝑥⦌𝐴
16		cbvralcsf.3	. . . . . 6 ⊢ Ⅎ𝑦𝜑
17	16	nfsb 2552	. . . . 5 ⊢ Ⅎ𝑦[𝑧 / 𝑥]𝜑
18	15, 17	nfan 1932	. . . 4 ⊢ Ⅎ𝑦(𝑧 ∈ ⦋𝑧 / 𝑥⦌𝐴 ∧ [𝑧 / 𝑥]𝜑)
19		nfv 1947	. . . 4 ⊢ Ⅎ𝑧(𝑦 ∈ 𝐵 ∧ 𝜓)
20		id 23	. . . . . 6 ⊢ (𝑧 = 𝑦 → 𝑧 = 𝑦)
21		csbeq1 3850	. . . . . . 7 ⊢ (𝑧 = 𝑦 → ⦋𝑧 / 𝑥⦌𝐴 = ⦋𝑦 / 𝑥⦌𝐴)
22		sbsbc 3743	. . . . . . . . 9 ⊢ ([𝑦 / 𝑥]𝑣 ∈ 𝐴 ↔ [𝑦 / 𝑥]𝑣 ∈ 𝐴)
23	22	abbii 2827	. . . . . . . 8 ⊢ {𝑣 ∣ [𝑦 / 𝑥]𝑣 ∈ 𝐴} = {𝑣 ∣ [𝑦 / 𝑥]𝑣 ∈ 𝐴}
24		cbvralcsf.2	. . . . . . . . . . . 12 ⊢ Ⅎ𝑥𝐵
25	24	nfcri 2914	. . . . . . . . . . 11 ⊢ Ⅎ𝑥 𝑣 ∈ 𝐵
26		cbvralcsf.5	. . . . . . . . . . . 12 ⊢ (𝑥 = 𝑦 → 𝐴 = 𝐵)
27	26	eleq2d 2846	. . . . . . . . . . 11 ⊢ (𝑥 = 𝑦 → (𝑣 ∈ 𝐴 ↔ 𝑣 ∈ 𝐵))
28	25, 27	sbie 2531	. . . . . . . . . 10 ⊢ ([𝑦 / 𝑥]𝑣 ∈ 𝐴 ↔ 𝑣 ∈ 𝐵)
29	28	bicomi 227	. . . . . . . . 9 ⊢ (𝑣 ∈ 𝐵 ↔ [𝑦 / 𝑥]𝑣 ∈ 𝐴)
30	29	eqabi 2895	. . . . . . . 8 ⊢ 𝐵 = {𝑣 ∣ [𝑦 / 𝑥]𝑣 ∈ 𝐴}
31		df-csb 3848	. . . . . . . 8 ⊢ ⦋𝑦 / 𝑥⦌𝐴 = {𝑣 ∣ [𝑦 / 𝑥]𝑣 ∈ 𝐴}
32	23, 30, 31	3eqtr4ri 2794	. . . . . . 7 ⊢ ⦋𝑦 / 𝑥⦌𝐴 = 𝐵
33	21, 32	eqtrdi 2811	. . . . . 6 ⊢ (𝑧 = 𝑦 → ⦋𝑧 / 𝑥⦌𝐴 = 𝐵)
34	20, 33	eleq12d 2854	. . . . 5 ⊢ (𝑧 = 𝑦 → (𝑧 ∈ ⦋𝑧 / 𝑥⦌𝐴 ↔ 𝑦 ∈ 𝐵))
35		sbequ 2120	. . . . . 6 ⊢ (𝑧 = 𝑦 → ([𝑧 / 𝑥]𝜑 ↔ [𝑦 / 𝑥]𝜑))
36		cbvralcsf.4	. . . . . . 7 ⊢ Ⅎ𝑥𝜓
37		cbvralcsf.6	. . . . . . 7 ⊢ (𝑥 = 𝑦 → (𝜑 ↔ 𝜓))
38	36, 37	sbie 2531	. . . . . 6 ⊢ ([𝑦 / 𝑥]𝜑 ↔ 𝜓)
39	35, 38	bitrdi 290	. . . . 5 ⊢ (𝑧 = 𝑦 → ([𝑧 / 𝑥]𝜑 ↔ 𝜓))
40	34, 39	anbi12d 644	. . . 4 ⊢ (𝑧 = 𝑦 → ((𝑧 ∈ ⦋𝑧 / 𝑥⦌𝐴 ∧ [𝑧 / 𝑥]𝜑) ↔ (𝑦 ∈ 𝐵 ∧ 𝜓)))
41	18, 19, 40	cbveu 2632	. . 3 ⊢ (∃!𝑧(𝑧 ∈ ⦋𝑧 / 𝑥⦌𝐴 ∧ [𝑧 / 𝑥]𝜑) ↔ ∃!𝑦(𝑦 ∈ 𝐵 ∧ 𝜓))
42	11, 41	bitri 278	. 2 ⊢ (∃!𝑥(𝑥 ∈ 𝐴 ∧ 𝜑) ↔ ∃!𝑦(𝑦 ∈ 𝐵 ∧ 𝜓))
43		df-reu 3366	. 2 ⊢ (∃!𝑥 ∈ 𝐴 𝜑 ↔ ∃!𝑥(𝑥 ∈ 𝐴 ∧ 𝜑))
44		df-reu 3366	. 2 ⊢ (∃!𝑦 ∈ 𝐵 𝜓 ↔ ∃!𝑦(𝑦 ∈ 𝐵 ∧ 𝜓))
45	42, 43, 44	3bitr4i 306	1 ⊢ (∃!𝑥 ∈ 𝐴 𝜑 ↔ ∃!𝑦 ∈ 𝐵 𝜓)

This proof depends on syntax axioms:   → wi 4   ↔ wb 209   ∧ wa 401   = wceq 1570  Ⅎwnf 1816  [wsb 2099   ∈ wcel 2145  ∃!weu 2593  {cab 2738  Ⅎwnfc 2907  ∃!wreu 3363  [wsbc 3739  ⦋csb 3847

This proof depends on axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1828  ax-4 1842  ax-5 1943  ax-6 2000  ax-7 2041  ax-8 2147  ax-9 2155  ax-10 2178  ax-11 2194  ax-12 2213  ax-13 2401  ax-ext 2732

This proof depends on definitions:  df-bi 210  df-an 402  df-or 862  df-tru 1573  df-ex 1813  df-nf 1817  df-sb 2100  df-mo 2564  df-eu 2594  df-clab 2739  df-cleq 2752  df-clel 2835  df-nfc 2909  df-reu 3366  df-sbc 3740  df-csb 3848

This theorem is used by: (None)