Theorem reupr 44974

Description: There is a unique unordered pair fulfilling a wff iff there are uniquely two sets fulfilling a corresponding wff. (Contributed by AV, 7-Apr-2023.)

Hypotheses

Ref	Expression
reupr.a	⊢ (𝑝 = {𝑎, 𝑏} → (𝜓 ↔ 𝜒))
reupr.x	⊢ (𝑝 = {𝑥, 𝑦} → (𝜓 ↔ 𝜃))

Assertion

Ref	Expression
reupr	⊢ (𝑋 ∈ 𝑉 → (∃!𝑝 ∈ (Pairs‘𝑋)𝜓 ↔ ∃𝑎 ∈ 𝑋 ∃𝑏 ∈ 𝑋 (𝜒 ∧ ∀𝑥 ∈ 𝑋 ∀𝑦 ∈ 𝑋 (𝜃 → {𝑥, 𝑦} = {𝑎, 𝑏}))))

Distinct variable groups:   𝑉,𝑎,𝑏,𝑝,𝑥,𝑦   𝑋,𝑎,𝑏,𝑝,𝑥,𝑦   𝜓,𝑎,𝑏,𝑥,𝑦   𝜃,𝑝   𝜒,𝑝

Allowed substitution hints:   𝜓(𝑝)   𝜒(𝑥,𝑦,𝑎,𝑏)   𝜃(𝑥,𝑦,𝑎,𝑏)

Proof of Theorem reupr

Dummy variables 𝑐 𝑑 𝑞 𝑤 are mutually distinct and distinct from all other variables.

Step	Hyp	Ref	Expression
1		nfsbc1v 3736	. . 3 ⊢ Ⅎ𝑝[𝑞 / 𝑝]𝜓
2		nfsbc1v 3736	. . 3 ⊢ Ⅎ𝑝[𝑤 / 𝑝]𝜓
3		sbceq1a 3727	. . 3 ⊢ (𝑝 = 𝑤 → (𝜓 ↔ [𝑤 / 𝑝]𝜓))
4		dfsbcq 3718	. . 3 ⊢ (𝑤 = 𝑞 → ([𝑤 / 𝑝]𝜓 ↔ [𝑞 / 𝑝]𝜓))
5	1, 2, 3, 4	reu8nf 3810	. 2 ⊢ (∃!𝑝 ∈ (Pairs‘𝑋)𝜓 ↔ ∃𝑝 ∈ (Pairs‘𝑋)(𝜓 ∧ ∀𝑞 ∈ (Pairs‘𝑋)([𝑞 / 𝑝]𝜓 → 𝑝 = 𝑞)))
6		sprel 44936	. . . . . 6 ⊢ (𝑝 ∈ (Pairs‘𝑋) → ∃𝑎 ∈ 𝑋 ∃𝑏 ∈ 𝑋 𝑝 = {𝑎, 𝑏})
7		reupr.a	. . . . . . . . . . . . . . 15 ⊢ (𝑝 = {𝑎, 𝑏} → (𝜓 ↔ 𝜒))
8	7	biimpcd 248	. . . . . . . . . . . . . 14 ⊢ (𝜓 → (𝑝 = {𝑎, 𝑏} → 𝜒))
9	8	adantr 481	. . . . . . . . . . . . 13 ⊢ ((𝜓 ∧ ∀𝑞 ∈ (Pairs‘𝑋)([𝑞 / 𝑝]𝜓 → 𝑝 = 𝑞)) → (𝑝 = {𝑎, 𝑏} → 𝜒))
10	9	ad2antlr 724	. . . . . . . . . . . 12 ⊢ (((𝑋 ∈ 𝑉 ∧ (𝜓 ∧ ∀𝑞 ∈ (Pairs‘𝑋)([𝑞 / 𝑝]𝜓 → 𝑝 = 𝑞))) ∧ (𝑎 ∈ 𝑋 ∧ 𝑏 ∈ 𝑋)) → (𝑝 = {𝑎, 𝑏} → 𝜒))
11	10	imp 407	. . . . . . . . . . 11 ⊢ ((((𝑋 ∈ 𝑉 ∧ (𝜓 ∧ ∀𝑞 ∈ (Pairs‘𝑋)([𝑞 / 𝑝]𝜓 → 𝑝 = 𝑞))) ∧ (𝑎 ∈ 𝑋 ∧ 𝑏 ∈ 𝑋)) ∧ 𝑝 = {𝑎, 𝑏}) → 𝜒)
12		pm3.22 460	. . . . . . . . . . . . . . . . . . 19 ⊢ (((𝑥 ∈ 𝑋 ∧ 𝑦 ∈ 𝑋) ∧ 𝑋 ∈ 𝑉) → (𝑋 ∈ 𝑉 ∧ (𝑥 ∈ 𝑋 ∧ 𝑦 ∈ 𝑋)))
13	12	adantr 481	. . . . . . . . . . . . . . . . . 18 ⊢ ((((𝑥 ∈ 𝑋 ∧ 𝑦 ∈ 𝑋) ∧ 𝑋 ∈ 𝑉) ∧ 𝜓) → (𝑋 ∈ 𝑉 ∧ (𝑥 ∈ 𝑋 ∧ 𝑦 ∈ 𝑋)))
14		prelspr 44938	. . . . . . . . . . . . . . . . . . 19 ⊢ ((𝑋 ∈ 𝑉 ∧ (𝑥 ∈ 𝑋 ∧ 𝑦 ∈ 𝑋)) → {𝑥, 𝑦} ∈ (Pairs‘𝑋))
15		dfsbcq 3718	. . . . . . . . . . . . . . . . . . . . 21 ⊢ (𝑞 = {𝑥, 𝑦} → ([𝑞 / 𝑝]𝜓 ↔ [{𝑥, 𝑦} / 𝑝]𝜓))
16		eqeq2 2750	. . . . . . . . . . . . . . . . . . . . 21 ⊢ (𝑞 = {𝑥, 𝑦} → (𝑝 = 𝑞 ↔ 𝑝 = {𝑥, 𝑦}))
17	15, 16	imbi12d 345	. . . . . . . . . . . . . . . . . . . 20 ⊢ (𝑞 = {𝑥, 𝑦} → (([𝑞 / 𝑝]𝜓 → 𝑝 = 𝑞) ↔ ([{𝑥, 𝑦} / 𝑝]𝜓 → 𝑝 = {𝑥, 𝑦})))
18	17	adantl 482	. . . . . . . . . . . . . . . . . . 19 ⊢ (((𝑋 ∈ 𝑉 ∧ (𝑥 ∈ 𝑋 ∧ 𝑦 ∈ 𝑋)) ∧ 𝑞 = {𝑥, 𝑦}) → (([𝑞 / 𝑝]𝜓 → 𝑝 = 𝑞) ↔ ([{𝑥, 𝑦} / 𝑝]𝜓 → 𝑝 = {𝑥, 𝑦})))
19	14, 18	rspcdv 3553	. . . . . . . . . . . . . . . . . 18 ⊢ ((𝑋 ∈ 𝑉 ∧ (𝑥 ∈ 𝑋 ∧ 𝑦 ∈ 𝑋)) → (∀𝑞 ∈ (Pairs‘𝑋)([𝑞 / 𝑝]𝜓 → 𝑝 = 𝑞) → ([{𝑥, 𝑦} / 𝑝]𝜓 → 𝑝 = {𝑥, 𝑦})))
20	13, 19	syl 17	. . . . . . . . . . . . . . . . 17 ⊢ ((((𝑥 ∈ 𝑋 ∧ 𝑦 ∈ 𝑋) ∧ 𝑋 ∈ 𝑉) ∧ 𝜓) → (∀𝑞 ∈ (Pairs‘𝑋)([𝑞 / 𝑝]𝜓 → 𝑝 = 𝑞) → ([{𝑥, 𝑦} / 𝑝]𝜓 → 𝑝 = {𝑥, 𝑦})))
21		zfpair2 5353	. . . . . . . . . . . . . . . . . . . . . . 23 ⊢ {𝑥, 𝑦} ∈ V
22		reupr.x	. . . . . . . . . . . . . . . . . . . . . . 23 ⊢ (𝑝 = {𝑥, 𝑦} → (𝜓 ↔ 𝜃))
23	21, 22	sbcie 3759	. . . . . . . . . . . . . . . . . . . . . 22 ⊢ ([{𝑥, 𝑦} / 𝑝]𝜓 ↔ 𝜃)
24		pm2.27 42	. . . . . . . . . . . . . . . . . . . . . 22 ⊢ ([{𝑥, 𝑦} / 𝑝]𝜓 → (([{𝑥, 𝑦} / 𝑝]𝜓 → 𝑝 = {𝑥, 𝑦}) → 𝑝 = {𝑥, 𝑦}))
25	23, 24	sylbir 234	. . . . . . . . . . . . . . . . . . . . 21 ⊢ (𝜃 → (([{𝑥, 𝑦} / 𝑝]𝜓 → 𝑝 = {𝑥, 𝑦}) → 𝑝 = {𝑥, 𝑦}))
26		eqcom 2745	. . . . . . . . . . . . . . . . . . . . 21 ⊢ ({𝑥, 𝑦} = 𝑝 ↔ 𝑝 = {𝑥, 𝑦})
27	25, 26	syl6ibr 251	. . . . . . . . . . . . . . . . . . . 20 ⊢ (𝜃 → (([{𝑥, 𝑦} / 𝑝]𝜓 → 𝑝 = {𝑥, 𝑦}) → {𝑥, 𝑦} = 𝑝))
28	27	com12 32	. . . . . . . . . . . . . . . . . . 19 ⊢ (([{𝑥, 𝑦} / 𝑝]𝜓 → 𝑝 = {𝑥, 𝑦}) → (𝜃 → {𝑥, 𝑦} = 𝑝))
29		eqeq2 2750	. . . . . . . . . . . . . . . . . . . . 21 ⊢ ({𝑎, 𝑏} = 𝑝 → ({𝑥, 𝑦} = {𝑎, 𝑏} ↔ {𝑥, 𝑦} = 𝑝))
30	29	eqcoms 2746	. . . . . . . . . . . . . . . . . . . 20 ⊢ (𝑝 = {𝑎, 𝑏} → ({𝑥, 𝑦} = {𝑎, 𝑏} ↔ {𝑥, 𝑦} = 𝑝))
31	30	imbi2d 341	. . . . . . . . . . . . . . . . . . 19 ⊢ (𝑝 = {𝑎, 𝑏} → ((𝜃 → {𝑥, 𝑦} = {𝑎, 𝑏}) ↔ (𝜃 → {𝑥, 𝑦} = 𝑝)))
32	28, 31	syl5ibrcom 246	. . . . . . . . . . . . . . . . . 18 ⊢ (([{𝑥, 𝑦} / 𝑝]𝜓 → 𝑝 = {𝑥, 𝑦}) → (𝑝 = {𝑎, 𝑏} → (𝜃 → {𝑥, 𝑦} = {𝑎, 𝑏})))
33	32	a1d 25	. . . . . . . . . . . . . . . . 17 ⊢ (([{𝑥, 𝑦} / 𝑝]𝜓 → 𝑝 = {𝑥, 𝑦}) → ((𝑎 ∈ 𝑋 ∧ 𝑏 ∈ 𝑋) → (𝑝 = {𝑎, 𝑏} → (𝜃 → {𝑥, 𝑦} = {𝑎, 𝑏}))))
34	20, 33	syl6 35	. . . . . . . . . . . . . . . 16 ⊢ ((((𝑥 ∈ 𝑋 ∧ 𝑦 ∈ 𝑋) ∧ 𝑋 ∈ 𝑉) ∧ 𝜓) → (∀𝑞 ∈ (Pairs‘𝑋)([𝑞 / 𝑝]𝜓 → 𝑝 = 𝑞) → ((𝑎 ∈ 𝑋 ∧ 𝑏 ∈ 𝑋) → (𝑝 = {𝑎, 𝑏} → (𝜃 → {𝑥, 𝑦} = {𝑎, 𝑏})))))
35	34	expimpd 454	. . . . . . . . . . . . . . 15 ⊢ (((𝑥 ∈ 𝑋 ∧ 𝑦 ∈ 𝑋) ∧ 𝑋 ∈ 𝑉) → ((𝜓 ∧ ∀𝑞 ∈ (Pairs‘𝑋)([𝑞 / 𝑝]𝜓 → 𝑝 = 𝑞)) → ((𝑎 ∈ 𝑋 ∧ 𝑏 ∈ 𝑋) → (𝑝 = {𝑎, 𝑏} → (𝜃 → {𝑥, 𝑦} = {𝑎, 𝑏})))))
36	35	expimpd 454	. . . . . . . . . . . . . 14 ⊢ ((𝑥 ∈ 𝑋 ∧ 𝑦 ∈ 𝑋) → ((𝑋 ∈ 𝑉 ∧ (𝜓 ∧ ∀𝑞 ∈ (Pairs‘𝑋)([𝑞 / 𝑝]𝜓 → 𝑝 = 𝑞))) → ((𝑎 ∈ 𝑋 ∧ 𝑏 ∈ 𝑋) → (𝑝 = {𝑎, 𝑏} → (𝜃 → {𝑥, 𝑦} = {𝑎, 𝑏})))))
37	36	imp4c 424	. . . . . . . . . . . . 13 ⊢ ((𝑥 ∈ 𝑋 ∧ 𝑦 ∈ 𝑋) → ((((𝑋 ∈ 𝑉 ∧ (𝜓 ∧ ∀𝑞 ∈ (Pairs‘𝑋)([𝑞 / 𝑝]𝜓 → 𝑝 = 𝑞))) ∧ (𝑎 ∈ 𝑋 ∧ 𝑏 ∈ 𝑋)) ∧ 𝑝 = {𝑎, 𝑏}) → (𝜃 → {𝑥, 𝑦} = {𝑎, 𝑏})))
38	37	impcom 408	. . . . . . . . . . . 12 ⊢ (((((𝑋 ∈ 𝑉 ∧ (𝜓 ∧ ∀𝑞 ∈ (Pairs‘𝑋)([𝑞 / 𝑝]𝜓 → 𝑝 = 𝑞))) ∧ (𝑎 ∈ 𝑋 ∧ 𝑏 ∈ 𝑋)) ∧ 𝑝 = {𝑎, 𝑏}) ∧ (𝑥 ∈ 𝑋 ∧ 𝑦 ∈ 𝑋)) → (𝜃 → {𝑥, 𝑦} = {𝑎, 𝑏}))
39	38	ralrimivva 3123	. . . . . . . . . . 11 ⊢ ((((𝑋 ∈ 𝑉 ∧ (𝜓 ∧ ∀𝑞 ∈ (Pairs‘𝑋)([𝑞 / 𝑝]𝜓 → 𝑝 = 𝑞))) ∧ (𝑎 ∈ 𝑋 ∧ 𝑏 ∈ 𝑋)) ∧ 𝑝 = {𝑎, 𝑏}) → ∀𝑥 ∈ 𝑋 ∀𝑦 ∈ 𝑋 (𝜃 → {𝑥, 𝑦} = {𝑎, 𝑏}))
40	11, 39	jca 512	. . . . . . . . . 10 ⊢ ((((𝑋 ∈ 𝑉 ∧ (𝜓 ∧ ∀𝑞 ∈ (Pairs‘𝑋)([𝑞 / 𝑝]𝜓 → 𝑝 = 𝑞))) ∧ (𝑎 ∈ 𝑋 ∧ 𝑏 ∈ 𝑋)) ∧ 𝑝 = {𝑎, 𝑏}) → (𝜒 ∧ ∀𝑥 ∈ 𝑋 ∀𝑦 ∈ 𝑋 (𝜃 → {𝑥, 𝑦} = {𝑎, 𝑏})))
41	40	ex 413	. . . . . . . . 9 ⊢ (((𝑋 ∈ 𝑉 ∧ (𝜓 ∧ ∀𝑞 ∈ (Pairs‘𝑋)([𝑞 / 𝑝]𝜓 → 𝑝 = 𝑞))) ∧ (𝑎 ∈ 𝑋 ∧ 𝑏 ∈ 𝑋)) → (𝑝 = {𝑎, 𝑏} → (𝜒 ∧ ∀𝑥 ∈ 𝑋 ∀𝑦 ∈ 𝑋 (𝜃 → {𝑥, 𝑦} = {𝑎, 𝑏}))))
42	41	reximdvva 3206	. . . . . . . 8 ⊢ ((𝑋 ∈ 𝑉 ∧ (𝜓 ∧ ∀𝑞 ∈ (Pairs‘𝑋)([𝑞 / 𝑝]𝜓 → 𝑝 = 𝑞))) → (∃𝑎 ∈ 𝑋 ∃𝑏 ∈ 𝑋 𝑝 = {𝑎, 𝑏} → ∃𝑎 ∈ 𝑋 ∃𝑏 ∈ 𝑋 (𝜒 ∧ ∀𝑥 ∈ 𝑋 ∀𝑦 ∈ 𝑋 (𝜃 → {𝑥, 𝑦} = {𝑎, 𝑏}))))
43	42	expcom 414	. . . . . . 7 ⊢ ((𝜓 ∧ ∀𝑞 ∈ (Pairs‘𝑋)([𝑞 / 𝑝]𝜓 → 𝑝 = 𝑞)) → (𝑋 ∈ 𝑉 → (∃𝑎 ∈ 𝑋 ∃𝑏 ∈ 𝑋 𝑝 = {𝑎, 𝑏} → ∃𝑎 ∈ 𝑋 ∃𝑏 ∈ 𝑋 (𝜒 ∧ ∀𝑥 ∈ 𝑋 ∀𝑦 ∈ 𝑋 (𝜃 → {𝑥, 𝑦} = {𝑎, 𝑏})))))
44	43	com13 88	. . . . . 6 ⊢ (∃𝑎 ∈ 𝑋 ∃𝑏 ∈ 𝑋 𝑝 = {𝑎, 𝑏} → (𝑋 ∈ 𝑉 → ((𝜓 ∧ ∀𝑞 ∈ (Pairs‘𝑋)([𝑞 / 𝑝]𝜓 → 𝑝 = 𝑞)) → ∃𝑎 ∈ 𝑋 ∃𝑏 ∈ 𝑋 (𝜒 ∧ ∀𝑥 ∈ 𝑋 ∀𝑦 ∈ 𝑋 (𝜃 → {𝑥, 𝑦} = {𝑎, 𝑏})))))
45	6, 44	syl 17	. . . . 5 ⊢ (𝑝 ∈ (Pairs‘𝑋) → (𝑋 ∈ 𝑉 → ((𝜓 ∧ ∀𝑞 ∈ (Pairs‘𝑋)([𝑞 / 𝑝]𝜓 → 𝑝 = 𝑞)) → ∃𝑎 ∈ 𝑋 ∃𝑏 ∈ 𝑋 (𝜒 ∧ ∀𝑥 ∈ 𝑋 ∀𝑦 ∈ 𝑋 (𝜃 → {𝑥, 𝑦} = {𝑎, 𝑏})))))
46	45	impcom 408	. . . 4 ⊢ ((𝑋 ∈ 𝑉 ∧ 𝑝 ∈ (Pairs‘𝑋)) → ((𝜓 ∧ ∀𝑞 ∈ (Pairs‘𝑋)([𝑞 / 𝑝]𝜓 → 𝑝 = 𝑞)) → ∃𝑎 ∈ 𝑋 ∃𝑏 ∈ 𝑋 (𝜒 ∧ ∀𝑥 ∈ 𝑋 ∀𝑦 ∈ 𝑋 (𝜃 → {𝑥, 𝑦} = {𝑎, 𝑏}))))
47	46	rexlimdva 3213	. . 3 ⊢ (𝑋 ∈ 𝑉 → (∃𝑝 ∈ (Pairs‘𝑋)(𝜓 ∧ ∀𝑞 ∈ (Pairs‘𝑋)([𝑞 / 𝑝]𝜓 → 𝑝 = 𝑞)) → ∃𝑎 ∈ 𝑋 ∃𝑏 ∈ 𝑋 (𝜒 ∧ ∀𝑥 ∈ 𝑋 ∀𝑦 ∈ 𝑋 (𝜃 → {𝑥, 𝑦} = {𝑎, 𝑏}))))
48		prelspr 44938	. . . . . . 7 ⊢ ((𝑋 ∈ 𝑉 ∧ (𝑎 ∈ 𝑋 ∧ 𝑏 ∈ 𝑋)) → {𝑎, 𝑏} ∈ (Pairs‘𝑋))
49	48	adantr 481	. . . . . 6 ⊢ (((𝑋 ∈ 𝑉 ∧ (𝑎 ∈ 𝑋 ∧ 𝑏 ∈ 𝑋)) ∧ (𝜒 ∧ ∀𝑥 ∈ 𝑋 ∀𝑦 ∈ 𝑋 (𝜃 → {𝑥, 𝑦} = {𝑎, 𝑏}))) → {𝑎, 𝑏} ∈ (Pairs‘𝑋))
50		simprl 768	. . . . . 6 ⊢ (((𝑋 ∈ 𝑉 ∧ (𝑎 ∈ 𝑋 ∧ 𝑏 ∈ 𝑋)) ∧ (𝜒 ∧ ∀𝑥 ∈ 𝑋 ∀𝑦 ∈ 𝑋 (𝜃 → {𝑥, 𝑦} = {𝑎, 𝑏}))) → 𝜒)
51		nfsbc1v 3736	. . . . . . . . . . . . . . . . . 18 ⊢ Ⅎ𝑥[𝑐 / 𝑥]𝜃
52		nfv 1917	. . . . . . . . . . . . . . . . . 18 ⊢ Ⅎ𝑥{𝑐, 𝑦} = {𝑎, 𝑏}
53	51, 52	nfim 1899	. . . . . . . . . . . . . . . . 17 ⊢ Ⅎ𝑥([𝑐 / 𝑥]𝜃 → {𝑐, 𝑦} = {𝑎, 𝑏})
54		nfsbc1v 3736	. . . . . . . . . . . . . . . . . 18 ⊢ Ⅎ𝑦[𝑑 / 𝑦][𝑐 / 𝑥]𝜃
55		nfv 1917	. . . . . . . . . . . . . . . . . 18 ⊢ Ⅎ𝑦{𝑐, 𝑑} = {𝑎, 𝑏}
56	54, 55	nfim 1899	. . . . . . . . . . . . . . . . 17 ⊢ Ⅎ𝑦([𝑑 / 𝑦][𝑐 / 𝑥]𝜃 → {𝑐, 𝑑} = {𝑎, 𝑏})
57		sbceq1a 3727	. . . . . . . . . . . . . . . . . 18 ⊢ (𝑥 = 𝑐 → (𝜃 ↔ [𝑐 / 𝑥]𝜃))
58		preq1 4669	. . . . . . . . . . . . . . . . . . 19 ⊢ (𝑥 = 𝑐 → {𝑥, 𝑦} = {𝑐, 𝑦})
59	58	eqeq1d 2740	. . . . . . . . . . . . . . . . . 18 ⊢ (𝑥 = 𝑐 → ({𝑥, 𝑦} = {𝑎, 𝑏} ↔ {𝑐, 𝑦} = {𝑎, 𝑏}))
60	57, 59	imbi12d 345	. . . . . . . . . . . . . . . . 17 ⊢ (𝑥 = 𝑐 → ((𝜃 → {𝑥, 𝑦} = {𝑎, 𝑏}) ↔ ([𝑐 / 𝑥]𝜃 → {𝑐, 𝑦} = {𝑎, 𝑏})))
61		sbceq1a 3727	. . . . . . . . . . . . . . . . . 18 ⊢ (𝑦 = 𝑑 → ([𝑐 / 𝑥]𝜃 ↔ [𝑑 / 𝑦][𝑐 / 𝑥]𝜃))
62		preq2 4670	. . . . . . . . . . . . . . . . . . 19 ⊢ (𝑦 = 𝑑 → {𝑐, 𝑦} = {𝑐, 𝑑})
63	62	eqeq1d 2740	. . . . . . . . . . . . . . . . . 18 ⊢ (𝑦 = 𝑑 → ({𝑐, 𝑦} = {𝑎, 𝑏} ↔ {𝑐, 𝑑} = {𝑎, 𝑏}))
64	61, 63	imbi12d 345	. . . . . . . . . . . . . . . . 17 ⊢ (𝑦 = 𝑑 → (([𝑐 / 𝑥]𝜃 → {𝑐, 𝑦} = {𝑎, 𝑏}) ↔ ([𝑑 / 𝑦][𝑐 / 𝑥]𝜃 → {𝑐, 𝑑} = {𝑎, 𝑏})))
65	53, 56, 60, 64	rspc2 3568	. . . . . . . . . . . . . . . 16 ⊢ ((𝑐 ∈ 𝑋 ∧ 𝑑 ∈ 𝑋) → (∀𝑥 ∈ 𝑋 ∀𝑦 ∈ 𝑋 (𝜃 → {𝑥, 𝑦} = {𝑎, 𝑏}) → ([𝑑 / 𝑦][𝑐 / 𝑥]𝜃 → {𝑐, 𝑑} = {𝑎, 𝑏})))
66	65	ad2antlr 724	. . . . . . . . . . . . . . 15 ⊢ ((((𝑋 ∈ 𝑉 ∧ (𝑎 ∈ 𝑋 ∧ 𝑏 ∈ 𝑋)) ∧ (𝑐 ∈ 𝑋 ∧ 𝑑 ∈ 𝑋)) ∧ 𝜒) → (∀𝑥 ∈ 𝑋 ∀𝑦 ∈ 𝑋 (𝜃 → {𝑥, 𝑦} = {𝑎, 𝑏}) → ([𝑑 / 𝑦][𝑐 / 𝑥]𝜃 → {𝑐, 𝑑} = {𝑎, 𝑏})))
67	22	sbcpr 44973	. . . . . . . . . . . . . . . . . 18 ⊢ ([{𝑐, 𝑑} / 𝑝]𝜓 ↔ [𝑑 / 𝑦][𝑐 / 𝑥]𝜃)
68		pm2.27 42	. . . . . . . . . . . . . . . . . 18 ⊢ ([𝑑 / 𝑦][𝑐 / 𝑥]𝜃 → (([𝑑 / 𝑦][𝑐 / 𝑥]𝜃 → {𝑐, 𝑑} = {𝑎, 𝑏}) → {𝑐, 𝑑} = {𝑎, 𝑏}))
69	67, 68	sylbi 216	. . . . . . . . . . . . . . . . 17 ⊢ ([{𝑐, 𝑑} / 𝑝]𝜓 → (([𝑑 / 𝑦][𝑐 / 𝑥]𝜃 → {𝑐, 𝑑} = {𝑎, 𝑏}) → {𝑐, 𝑑} = {𝑎, 𝑏}))
70		eqcom 2745	. . . . . . . . . . . . . . . . 17 ⊢ ({𝑎, 𝑏} = {𝑐, 𝑑} ↔ {𝑐, 𝑑} = {𝑎, 𝑏})
71	69, 70	syl6ibr 251	. . . . . . . . . . . . . . . 16 ⊢ ([{𝑐, 𝑑} / 𝑝]𝜓 → (([𝑑 / 𝑦][𝑐 / 𝑥]𝜃 → {𝑐, 𝑑} = {𝑎, 𝑏}) → {𝑎, 𝑏} = {𝑐, 𝑑}))
72	71	com12 32	. . . . . . . . . . . . . . 15 ⊢ (([𝑑 / 𝑦][𝑐 / 𝑥]𝜃 → {𝑐, 𝑑} = {𝑎, 𝑏}) → ([{𝑐, 𝑑} / 𝑝]𝜓 → {𝑎, 𝑏} = {𝑐, 𝑑}))
73	66, 72	syl6 35	. . . . . . . . . . . . . 14 ⊢ ((((𝑋 ∈ 𝑉 ∧ (𝑎 ∈ 𝑋 ∧ 𝑏 ∈ 𝑋)) ∧ (𝑐 ∈ 𝑋 ∧ 𝑑 ∈ 𝑋)) ∧ 𝜒) → (∀𝑥 ∈ 𝑋 ∀𝑦 ∈ 𝑋 (𝜃 → {𝑥, 𝑦} = {𝑎, 𝑏}) → ([{𝑐, 𝑑} / 𝑝]𝜓 → {𝑎, 𝑏} = {𝑐, 𝑑})))
74	73	expimpd 454	. . . . . . . . . . . . 13 ⊢ (((𝑋 ∈ 𝑉 ∧ (𝑎 ∈ 𝑋 ∧ 𝑏 ∈ 𝑋)) ∧ (𝑐 ∈ 𝑋 ∧ 𝑑 ∈ 𝑋)) → ((𝜒 ∧ ∀𝑥 ∈ 𝑋 ∀𝑦 ∈ 𝑋 (𝜃 → {𝑥, 𝑦} = {𝑎, 𝑏})) → ([{𝑐, 𝑑} / 𝑝]𝜓 → {𝑎, 𝑏} = {𝑐, 𝑑})))
75	74	expcom 414	. . . . . . . . . . . 12 ⊢ ((𝑐 ∈ 𝑋 ∧ 𝑑 ∈ 𝑋) → ((𝑋 ∈ 𝑉 ∧ (𝑎 ∈ 𝑋 ∧ 𝑏 ∈ 𝑋)) → ((𝜒 ∧ ∀𝑥 ∈ 𝑋 ∀𝑦 ∈ 𝑋 (𝜃 → {𝑥, 𝑦} = {𝑎, 𝑏})) → ([{𝑐, 𝑑} / 𝑝]𝜓 → {𝑎, 𝑏} = {𝑐, 𝑑}))))
76	75	impd 411	. . . . . . . . . . 11 ⊢ ((𝑐 ∈ 𝑋 ∧ 𝑑 ∈ 𝑋) → (((𝑋 ∈ 𝑉 ∧ (𝑎 ∈ 𝑋 ∧ 𝑏 ∈ 𝑋)) ∧ (𝜒 ∧ ∀𝑥 ∈ 𝑋 ∀𝑦 ∈ 𝑋 (𝜃 → {𝑥, 𝑦} = {𝑎, 𝑏}))) → ([{𝑐, 𝑑} / 𝑝]𝜓 → {𝑎, 𝑏} = {𝑐, 𝑑})))
77	76	impcom 408	. . . . . . . . . 10 ⊢ ((((𝑋 ∈ 𝑉 ∧ (𝑎 ∈ 𝑋 ∧ 𝑏 ∈ 𝑋)) ∧ (𝜒 ∧ ∀𝑥 ∈ 𝑋 ∀𝑦 ∈ 𝑋 (𝜃 → {𝑥, 𝑦} = {𝑎, 𝑏}))) ∧ (𝑐 ∈ 𝑋 ∧ 𝑑 ∈ 𝑋)) → ([{𝑐, 𝑑} / 𝑝]𝜓 → {𝑎, 𝑏} = {𝑐, 𝑑}))
78		dfsbcq 3718	. . . . . . . . . . 11 ⊢ (𝑞 = {𝑐, 𝑑} → ([𝑞 / 𝑝]𝜓 ↔ [{𝑐, 𝑑} / 𝑝]𝜓))
79		eqeq2 2750	. . . . . . . . . . 11 ⊢ (𝑞 = {𝑐, 𝑑} → ({𝑎, 𝑏} = 𝑞 ↔ {𝑎, 𝑏} = {𝑐, 𝑑}))
80	78, 79	imbi12d 345	. . . . . . . . . 10 ⊢ (𝑞 = {𝑐, 𝑑} → (([𝑞 / 𝑝]𝜓 → {𝑎, 𝑏} = 𝑞) ↔ ([{𝑐, 𝑑} / 𝑝]𝜓 → {𝑎, 𝑏} = {𝑐, 𝑑})))
81	77, 80	syl5ibrcom 246	. . . . . . . . 9 ⊢ ((((𝑋 ∈ 𝑉 ∧ (𝑎 ∈ 𝑋 ∧ 𝑏 ∈ 𝑋)) ∧ (𝜒 ∧ ∀𝑥 ∈ 𝑋 ∀𝑦 ∈ 𝑋 (𝜃 → {𝑥, 𝑦} = {𝑎, 𝑏}))) ∧ (𝑐 ∈ 𝑋 ∧ 𝑑 ∈ 𝑋)) → (𝑞 = {𝑐, 𝑑} → ([𝑞 / 𝑝]𝜓 → {𝑎, 𝑏} = 𝑞)))
82	81	rexlimdvva 3223	. . . . . . . 8 ⊢ (((𝑋 ∈ 𝑉 ∧ (𝑎 ∈ 𝑋 ∧ 𝑏 ∈ 𝑋)) ∧ (𝜒 ∧ ∀𝑥 ∈ 𝑋 ∀𝑦 ∈ 𝑋 (𝜃 → {𝑥, 𝑦} = {𝑎, 𝑏}))) → (∃𝑐 ∈ 𝑋 ∃𝑑 ∈ 𝑋 𝑞 = {𝑐, 𝑑} → ([𝑞 / 𝑝]𝜓 → {𝑎, 𝑏} = 𝑞)))
83		sprel 44936	. . . . . . . 8 ⊢ (𝑞 ∈ (Pairs‘𝑋) → ∃𝑐 ∈ 𝑋 ∃𝑑 ∈ 𝑋 𝑞 = {𝑐, 𝑑})
84	82, 83	impel 506	. . . . . . 7 ⊢ ((((𝑋 ∈ 𝑉 ∧ (𝑎 ∈ 𝑋 ∧ 𝑏 ∈ 𝑋)) ∧ (𝜒 ∧ ∀𝑥 ∈ 𝑋 ∀𝑦 ∈ 𝑋 (𝜃 → {𝑥, 𝑦} = {𝑎, 𝑏}))) ∧ 𝑞 ∈ (Pairs‘𝑋)) → ([𝑞 / 𝑝]𝜓 → {𝑎, 𝑏} = 𝑞))
85	84	ralrimiva 3103	. . . . . 6 ⊢ (((𝑋 ∈ 𝑉 ∧ (𝑎 ∈ 𝑋 ∧ 𝑏 ∈ 𝑋)) ∧ (𝜒 ∧ ∀𝑥 ∈ 𝑋 ∀𝑦 ∈ 𝑋 (𝜃 → {𝑥, 𝑦} = {𝑎, 𝑏}))) → ∀𝑞 ∈ (Pairs‘𝑋)([𝑞 / 𝑝]𝜓 → {𝑎, 𝑏} = 𝑞))
86		nfv 1917	. . . . . . . 8 ⊢ Ⅎ𝑝𝜒
87		nfcv 2907	. . . . . . . . 9 ⊢ Ⅎ𝑝(Pairs‘𝑋)
88		nfv 1917	. . . . . . . . . 10 ⊢ Ⅎ𝑝{𝑎, 𝑏} = 𝑞
89	1, 88	nfim 1899	. . . . . . . . 9 ⊢ Ⅎ𝑝([𝑞 / 𝑝]𝜓 → {𝑎, 𝑏} = 𝑞)
90	87, 89	nfralw 3151	. . . . . . . 8 ⊢ Ⅎ𝑝∀𝑞 ∈ (Pairs‘𝑋)([𝑞 / 𝑝]𝜓 → {𝑎, 𝑏} = 𝑞)
91	86, 90	nfan 1902	. . . . . . 7 ⊢ Ⅎ𝑝(𝜒 ∧ ∀𝑞 ∈ (Pairs‘𝑋)([𝑞 / 𝑝]𝜓 → {𝑎, 𝑏} = 𝑞))
92		eqeq1 2742	. . . . . . . . . 10 ⊢ (𝑝 = {𝑎, 𝑏} → (𝑝 = 𝑞 ↔ {𝑎, 𝑏} = 𝑞))
93	92	imbi2d 341	. . . . . . . . 9 ⊢ (𝑝 = {𝑎, 𝑏} → (([𝑞 / 𝑝]𝜓 → 𝑝 = 𝑞) ↔ ([𝑞 / 𝑝]𝜓 → {𝑎, 𝑏} = 𝑞)))
94	93	ralbidv 3112	. . . . . . . 8 ⊢ (𝑝 = {𝑎, 𝑏} → (∀𝑞 ∈ (Pairs‘𝑋)([𝑞 / 𝑝]𝜓 → 𝑝 = 𝑞) ↔ ∀𝑞 ∈ (Pairs‘𝑋)([𝑞 / 𝑝]𝜓 → {𝑎, 𝑏} = 𝑞)))
95	7, 94	anbi12d 631	. . . . . . 7 ⊢ (𝑝 = {𝑎, 𝑏} → ((𝜓 ∧ ∀𝑞 ∈ (Pairs‘𝑋)([𝑞 / 𝑝]𝜓 → 𝑝 = 𝑞)) ↔ (𝜒 ∧ ∀𝑞 ∈ (Pairs‘𝑋)([𝑞 / 𝑝]𝜓 → {𝑎, 𝑏} = 𝑞))))
96	91, 95	rspce 3550	. . . . . 6 ⊢ (({𝑎, 𝑏} ∈ (Pairs‘𝑋) ∧ (𝜒 ∧ ∀𝑞 ∈ (Pairs‘𝑋)([𝑞 / 𝑝]𝜓 → {𝑎, 𝑏} = 𝑞))) → ∃𝑝 ∈ (Pairs‘𝑋)(𝜓 ∧ ∀𝑞 ∈ (Pairs‘𝑋)([𝑞 / 𝑝]𝜓 → 𝑝 = 𝑞)))
97	49, 50, 85, 96	syl12anc 834	. . . . 5 ⊢ (((𝑋 ∈ 𝑉 ∧ (𝑎 ∈ 𝑋 ∧ 𝑏 ∈ 𝑋)) ∧ (𝜒 ∧ ∀𝑥 ∈ 𝑋 ∀𝑦 ∈ 𝑋 (𝜃 → {𝑥, 𝑦} = {𝑎, 𝑏}))) → ∃𝑝 ∈ (Pairs‘𝑋)(𝜓 ∧ ∀𝑞 ∈ (Pairs‘𝑋)([𝑞 / 𝑝]𝜓 → 𝑝 = 𝑞)))
98	97	ex 413	. . . 4 ⊢ ((𝑋 ∈ 𝑉 ∧ (𝑎 ∈ 𝑋 ∧ 𝑏 ∈ 𝑋)) → ((𝜒 ∧ ∀𝑥 ∈ 𝑋 ∀𝑦 ∈ 𝑋 (𝜃 → {𝑥, 𝑦} = {𝑎, 𝑏})) → ∃𝑝 ∈ (Pairs‘𝑋)(𝜓 ∧ ∀𝑞 ∈ (Pairs‘𝑋)([𝑞 / 𝑝]𝜓 → 𝑝 = 𝑞))))
99	98	rexlimdvva 3223	. . 3 ⊢ (𝑋 ∈ 𝑉 → (∃𝑎 ∈ 𝑋 ∃𝑏 ∈ 𝑋 (𝜒 ∧ ∀𝑥 ∈ 𝑋 ∀𝑦 ∈ 𝑋 (𝜃 → {𝑥, 𝑦} = {𝑎, 𝑏})) → ∃𝑝 ∈ (Pairs‘𝑋)(𝜓 ∧ ∀𝑞 ∈ (Pairs‘𝑋)([𝑞 / 𝑝]𝜓 → 𝑝 = 𝑞))))
100	47, 99	impbid 211	. 2 ⊢ (𝑋 ∈ 𝑉 → (∃𝑝 ∈ (Pairs‘𝑋)(𝜓 ∧ ∀𝑞 ∈ (Pairs‘𝑋)([𝑞 / 𝑝]𝜓 → 𝑝 = 𝑞)) ↔ ∃𝑎 ∈ 𝑋 ∃𝑏 ∈ 𝑋 (𝜒 ∧ ∀𝑥 ∈ 𝑋 ∀𝑦 ∈ 𝑋 (𝜃 → {𝑥, 𝑦} = {𝑎, 𝑏}))))
101	5, 100	syl5bb 283	1 ⊢ (𝑋 ∈ 𝑉 → (∃!𝑝 ∈ (Pairs‘𝑋)𝜓 ↔ ∃𝑎 ∈ 𝑋 ∃𝑏 ∈ 𝑋 (𝜒 ∧ ∀𝑥 ∈ 𝑋 ∀𝑦 ∈ 𝑋 (𝜃 → {𝑥, 𝑦} = {𝑎, 𝑏}))))

Syntax hints:   → wi 4   ↔ wb 205   ∧ wa 396   = wceq 1539   ∈ wcel 2106  ∀wral 3064  ∃wrex 3065  ∃!wreu 3066  [wsbc 3716  {cpr 4563  ‘cfv 6433  Pairscspr 44929

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1798  ax-4 1812  ax-5 1913  ax-6 1971  ax-7 2011  ax-8 2108  ax-9 2116  ax-10 2137  ax-11 2154  ax-12 2171  ax-ext 2709  ax-rep 5209  ax-sep 5223  ax-nul 5230  ax-pr 5352  ax-un 7588

This theorem depends on definitions:  df-bi 206  df-an 397  df-or 845  df-3an 1088  df-tru 1542  df-fal 1552  df-ex 1783  df-nf 1787  df-sb 2068  df-mo 2540  df-eu 2569  df-clab 2716  df-cleq 2730  df-clel 2816  df-nfc 2889  df-ral 3069  df-rex 3070  df-rmo 3071  df-reu 3072  df-rab 3073  df-v 3434  df-sbc 3717  df-csb 3833  df-dif 3890  df-un 3892  df-in 3894  df-ss 3904  df-nul 4257  df-if 4460  df-pw 4535  df-sn 4562  df-pr 4564  df-op 4568  df-uni 4840  df-iun 4926  df-br 5075  df-opab 5137  df-mpt 5158  df-id 5489  df-xp 5595  df-rel 5596  df-cnv 5597  df-co 5598  df-dm 5599  df-iota 6391  df-fun 6435  df-fv 6441  df-spr 44930

This theorem is referenced by:  reuprpr  44975  reuopreuprim  44978