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Theorem brprcneu 5171
 Description: If 𝐴 is a proper class, then there is no unique binary relationship with 𝐴 as the first element. (Contributed by Scott Fenton, 7-Oct-2017.)
Assertion
Ref Expression
brprcneu 𝐴 ∈ V → ¬ ∃!𝑥 𝐴𝐹𝑥)
Distinct variable groups:   𝑥,𝐴   𝑥,𝐹

Proof of Theorem brprcneu
Dummy variable 𝑦 is distinct from all other variables.
StepHypRef Expression
1 dtruex 4283 . . . . . . . . 9 𝑦 ¬ 𝑦 = 𝑥
2 equcom 1593 . . . . . . . . . . 11 (𝑥 = 𝑦𝑦 = 𝑥)
32notbii 594 . . . . . . . . . 10 𝑥 = 𝑦 ↔ ¬ 𝑦 = 𝑥)
43exbii 1496 . . . . . . . . 9 (∃𝑦 ¬ 𝑥 = 𝑦 ↔ ∃𝑦 ¬ 𝑦 = 𝑥)
51, 4mpbir 134 . . . . . . . 8 𝑦 ¬ 𝑥 = 𝑦
65jctr 298 . . . . . . 7 (∅ ∈ 𝐹 → (∅ ∈ 𝐹 ∧ ∃𝑦 ¬ 𝑥 = 𝑦))
7 19.42v 1786 . . . . . . 7 (∃𝑦(∅ ∈ 𝐹 ∧ ¬ 𝑥 = 𝑦) ↔ (∅ ∈ 𝐹 ∧ ∃𝑦 ¬ 𝑥 = 𝑦))
86, 7sylibr 137 . . . . . 6 (∅ ∈ 𝐹 → ∃𝑦(∅ ∈ 𝐹 ∧ ¬ 𝑥 = 𝑦))
9 opprc1 3571 . . . . . . . 8 𝐴 ∈ V → ⟨𝐴, 𝑥⟩ = ∅)
109eleq1d 2106 . . . . . . 7 𝐴 ∈ V → (⟨𝐴, 𝑥⟩ ∈ 𝐹 ↔ ∅ ∈ 𝐹))
11 opprc1 3571 . . . . . . . . . . . 12 𝐴 ∈ V → ⟨𝐴, 𝑦⟩ = ∅)
1211eleq1d 2106 . . . . . . . . . . 11 𝐴 ∈ V → (⟨𝐴, 𝑦⟩ ∈ 𝐹 ↔ ∅ ∈ 𝐹))
1310, 12anbi12d 442 . . . . . . . . . 10 𝐴 ∈ V → ((⟨𝐴, 𝑥⟩ ∈ 𝐹 ∧ ⟨𝐴, 𝑦⟩ ∈ 𝐹) ↔ (∅ ∈ 𝐹 ∧ ∅ ∈ 𝐹)))
14 anidm 376 . . . . . . . . . 10 ((∅ ∈ 𝐹 ∧ ∅ ∈ 𝐹) ↔ ∅ ∈ 𝐹)
1513, 14syl6bb 185 . . . . . . . . 9 𝐴 ∈ V → ((⟨𝐴, 𝑥⟩ ∈ 𝐹 ∧ ⟨𝐴, 𝑦⟩ ∈ 𝐹) ↔ ∅ ∈ 𝐹))
1615anbi1d 438 . . . . . . . 8 𝐴 ∈ V → (((⟨𝐴, 𝑥⟩ ∈ 𝐹 ∧ ⟨𝐴, 𝑦⟩ ∈ 𝐹) ∧ ¬ 𝑥 = 𝑦) ↔ (∅ ∈ 𝐹 ∧ ¬ 𝑥 = 𝑦)))
1716exbidv 1706 . . . . . . 7 𝐴 ∈ V → (∃𝑦((⟨𝐴, 𝑥⟩ ∈ 𝐹 ∧ ⟨𝐴, 𝑦⟩ ∈ 𝐹) ∧ ¬ 𝑥 = 𝑦) ↔ ∃𝑦(∅ ∈ 𝐹 ∧ ¬ 𝑥 = 𝑦)))
1810, 17imbi12d 223 . . . . . 6 𝐴 ∈ V → ((⟨𝐴, 𝑥⟩ ∈ 𝐹 → ∃𝑦((⟨𝐴, 𝑥⟩ ∈ 𝐹 ∧ ⟨𝐴, 𝑦⟩ ∈ 𝐹) ∧ ¬ 𝑥 = 𝑦)) ↔ (∅ ∈ 𝐹 → ∃𝑦(∅ ∈ 𝐹 ∧ ¬ 𝑥 = 𝑦))))
198, 18mpbiri 157 . . . . 5 𝐴 ∈ V → (⟨𝐴, 𝑥⟩ ∈ 𝐹 → ∃𝑦((⟨𝐴, 𝑥⟩ ∈ 𝐹 ∧ ⟨𝐴, 𝑦⟩ ∈ 𝐹) ∧ ¬ 𝑥 = 𝑦)))
20 df-br 3765 . . . . 5 (𝐴𝐹𝑥 ↔ ⟨𝐴, 𝑥⟩ ∈ 𝐹)
21 df-br 3765 . . . . . . . 8 (𝐴𝐹𝑦 ↔ ⟨𝐴, 𝑦⟩ ∈ 𝐹)
2220, 21anbi12i 433 . . . . . . 7 ((𝐴𝐹𝑥𝐴𝐹𝑦) ↔ (⟨𝐴, 𝑥⟩ ∈ 𝐹 ∧ ⟨𝐴, 𝑦⟩ ∈ 𝐹))
2322anbi1i 431 . . . . . 6 (((𝐴𝐹𝑥𝐴𝐹𝑦) ∧ ¬ 𝑥 = 𝑦) ↔ ((⟨𝐴, 𝑥⟩ ∈ 𝐹 ∧ ⟨𝐴, 𝑦⟩ ∈ 𝐹) ∧ ¬ 𝑥 = 𝑦))
2423exbii 1496 . . . . 5 (∃𝑦((𝐴𝐹𝑥𝐴𝐹𝑦) ∧ ¬ 𝑥 = 𝑦) ↔ ∃𝑦((⟨𝐴, 𝑥⟩ ∈ 𝐹 ∧ ⟨𝐴, 𝑦⟩ ∈ 𝐹) ∧ ¬ 𝑥 = 𝑦))
2519, 20, 243imtr4g 194 . . . 4 𝐴 ∈ V → (𝐴𝐹𝑥 → ∃𝑦((𝐴𝐹𝑥𝐴𝐹𝑦) ∧ ¬ 𝑥 = 𝑦)))
2625eximdv 1760 . . 3 𝐴 ∈ V → (∃𝑥 𝐴𝐹𝑥 → ∃𝑥𝑦((𝐴𝐹𝑥𝐴𝐹𝑦) ∧ ¬ 𝑥 = 𝑦)))
27 exanaliim 1538 . . . . . 6 (∃𝑦((𝐴𝐹𝑥𝐴𝐹𝑦) ∧ ¬ 𝑥 = 𝑦) → ¬ ∀𝑦((𝐴𝐹𝑥𝐴𝐹𝑦) → 𝑥 = 𝑦))
2827eximi 1491 . . . . 5 (∃𝑥𝑦((𝐴𝐹𝑥𝐴𝐹𝑦) ∧ ¬ 𝑥 = 𝑦) → ∃𝑥 ¬ ∀𝑦((𝐴𝐹𝑥𝐴𝐹𝑦) → 𝑥 = 𝑦))
29 exnalim 1537 . . . . 5 (∃𝑥 ¬ ∀𝑦((𝐴𝐹𝑥𝐴𝐹𝑦) → 𝑥 = 𝑦) → ¬ ∀𝑥𝑦((𝐴𝐹𝑥𝐴𝐹𝑦) → 𝑥 = 𝑦))
3028, 29syl 14 . . . 4 (∃𝑥𝑦((𝐴𝐹𝑥𝐴𝐹𝑦) ∧ ¬ 𝑥 = 𝑦) → ¬ ∀𝑥𝑦((𝐴𝐹𝑥𝐴𝐹𝑦) → 𝑥 = 𝑦))
31 breq2 3768 . . . . . 6 (𝑥 = 𝑦 → (𝐴𝐹𝑥𝐴𝐹𝑦))
3231mo4 1961 . . . . 5 (∃*𝑥 𝐴𝐹𝑥 ↔ ∀𝑥𝑦((𝐴𝐹𝑥𝐴𝐹𝑦) → 𝑥 = 𝑦))
3332notbii 594 . . . 4 (¬ ∃*𝑥 𝐴𝐹𝑥 ↔ ¬ ∀𝑥𝑦((𝐴𝐹𝑥𝐴𝐹𝑦) → 𝑥 = 𝑦))
3430, 33sylibr 137 . . 3 (∃𝑥𝑦((𝐴𝐹𝑥𝐴𝐹𝑦) ∧ ¬ 𝑥 = 𝑦) → ¬ ∃*𝑥 𝐴𝐹𝑥)
3526, 34syl6 29 . 2 𝐴 ∈ V → (∃𝑥 𝐴𝐹𝑥 → ¬ ∃*𝑥 𝐴𝐹𝑥))
36 eu5 1947 . . . 4 (∃!𝑥 𝐴𝐹𝑥 ↔ (∃𝑥 𝐴𝐹𝑥 ∧ ∃*𝑥 𝐴𝐹𝑥))
3736notbii 594 . . 3 (¬ ∃!𝑥 𝐴𝐹𝑥 ↔ ¬ (∃𝑥 𝐴𝐹𝑥 ∧ ∃*𝑥 𝐴𝐹𝑥))
38 imnan 624 . . 3 ((∃𝑥 𝐴𝐹𝑥 → ¬ ∃*𝑥 𝐴𝐹𝑥) ↔ ¬ (∃𝑥 𝐴𝐹𝑥 ∧ ∃*𝑥 𝐴𝐹𝑥))
3937, 38bitr4i 176 . 2 (¬ ∃!𝑥 𝐴𝐹𝑥 ↔ (∃𝑥 𝐴𝐹𝑥 → ¬ ∃*𝑥 𝐴𝐹𝑥))
4035, 39sylibr 137 1 𝐴 ∈ V → ¬ ∃!𝑥 𝐴𝐹𝑥)
 Colors of variables: wff set class Syntax hints:  ¬ wn 3   → wi 4   ∧ wa 97  ∀wal 1241  ∃wex 1381   ∈ wcel 1393  ∃!weu 1900  ∃*wmo 1901  Vcvv 2557  ∅c0 3224  ⟨cop 3378   class class class wbr 3764 This theorem was proved from axioms:  ax-1 5  ax-2 6  ax-mp 7  ax-ia1 99  ax-ia2 100  ax-ia3 101  ax-in1 544  ax-in2 545  ax-io 630  ax-5 1336  ax-7 1337  ax-gen 1338  ax-ie1 1382  ax-ie2 1383  ax-8 1395  ax-10 1396  ax-11 1397  ax-i12 1398  ax-bndl 1399  ax-4 1400  ax-14 1405  ax-17 1419  ax-i9 1423  ax-ial 1427  ax-i5r 1428  ax-ext 2022  ax-sep 3875  ax-pow 3927  ax-setind 4262 This theorem depends on definitions:  df-bi 110  df-3an 887  df-tru 1246  df-fal 1249  df-nf 1350  df-sb 1646  df-eu 1903  df-mo 1904  df-clab 2027  df-cleq 2033  df-clel 2036  df-nfc 2167  df-ne 2206  df-ral 2311  df-v 2559  df-dif 2920  df-un 2922  df-in 2924  df-ss 2931  df-nul 3225  df-pw 3361  df-sn 3381  df-pr 3382  df-op 3384  df-br 3765 This theorem is referenced by:  fvprc  5172
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