MPE Home Metamath Proof Explorer < Previous   Next >
Nearby theorems
Mirrors  >  Home  >  MPE Home  >  Th. List  >  brprcneu Structured version   Visualization version   GIF version

Theorem brprcneu 6081
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 dtru 4778 . . . . . . . . 9 ¬ ∀𝑦 𝑦 = 𝑥
2 exnal 1743 . . . . . . . . . 10 (∃𝑦 ¬ 𝑥 = 𝑦 ↔ ¬ ∀𝑦 𝑥 = 𝑦)
3 equcom 1931 . . . . . . . . . . 11 (𝑥 = 𝑦𝑦 = 𝑥)
43albii 1736 . . . . . . . . . 10 (∀𝑦 𝑥 = 𝑦 ↔ ∀𝑦 𝑦 = 𝑥)
52, 4xchbinx 322 . . . . . . . . 9 (∃𝑦 ¬ 𝑥 = 𝑦 ↔ ¬ ∀𝑦 𝑦 = 𝑥)
61, 5mpbir 219 . . . . . . . 8 𝑦 ¬ 𝑥 = 𝑦
76jctr 562 . . . . . . 7 (∅ ∈ 𝐹 → (∅ ∈ 𝐹 ∧ ∃𝑦 ¬ 𝑥 = 𝑦))
8 19.42v 1904 . . . . . . 7 (∃𝑦(∅ ∈ 𝐹 ∧ ¬ 𝑥 = 𝑦) ↔ (∅ ∈ 𝐹 ∧ ∃𝑦 ¬ 𝑥 = 𝑦))
97, 8sylibr 222 . . . . . 6 (∅ ∈ 𝐹 → ∃𝑦(∅ ∈ 𝐹 ∧ ¬ 𝑥 = 𝑦))
10 opprc1 4357 . . . . . . . 8 𝐴 ∈ V → ⟨𝐴, 𝑥⟩ = ∅)
1110eleq1d 2671 . . . . . . 7 𝐴 ∈ V → (⟨𝐴, 𝑥⟩ ∈ 𝐹 ↔ ∅ ∈ 𝐹))
12 opprc1 4357 . . . . . . . . . . . 12 𝐴 ∈ V → ⟨𝐴, 𝑦⟩ = ∅)
1312eleq1d 2671 . . . . . . . . . . 11 𝐴 ∈ V → (⟨𝐴, 𝑦⟩ ∈ 𝐹 ↔ ∅ ∈ 𝐹))
1411, 13anbi12d 742 . . . . . . . . . 10 𝐴 ∈ V → ((⟨𝐴, 𝑥⟩ ∈ 𝐹 ∧ ⟨𝐴, 𝑦⟩ ∈ 𝐹) ↔ (∅ ∈ 𝐹 ∧ ∅ ∈ 𝐹)))
15 anidm 673 . . . . . . . . . 10 ((∅ ∈ 𝐹 ∧ ∅ ∈ 𝐹) ↔ ∅ ∈ 𝐹)
1614, 15syl6bb 274 . . . . . . . . 9 𝐴 ∈ V → ((⟨𝐴, 𝑥⟩ ∈ 𝐹 ∧ ⟨𝐴, 𝑦⟩ ∈ 𝐹) ↔ ∅ ∈ 𝐹))
1716anbi1d 736 . . . . . . . 8 𝐴 ∈ V → (((⟨𝐴, 𝑥⟩ ∈ 𝐹 ∧ ⟨𝐴, 𝑦⟩ ∈ 𝐹) ∧ ¬ 𝑥 = 𝑦) ↔ (∅ ∈ 𝐹 ∧ ¬ 𝑥 = 𝑦)))
1817exbidv 1836 . . . . . . 7 𝐴 ∈ V → (∃𝑦((⟨𝐴, 𝑥⟩ ∈ 𝐹 ∧ ⟨𝐴, 𝑦⟩ ∈ 𝐹) ∧ ¬ 𝑥 = 𝑦) ↔ ∃𝑦(∅ ∈ 𝐹 ∧ ¬ 𝑥 = 𝑦)))
1911, 18imbi12d 332 . . . . . 6 𝐴 ∈ V → ((⟨𝐴, 𝑥⟩ ∈ 𝐹 → ∃𝑦((⟨𝐴, 𝑥⟩ ∈ 𝐹 ∧ ⟨𝐴, 𝑦⟩ ∈ 𝐹) ∧ ¬ 𝑥 = 𝑦)) ↔ (∅ ∈ 𝐹 → ∃𝑦(∅ ∈ 𝐹 ∧ ¬ 𝑥 = 𝑦))))
209, 19mpbiri 246 . . . . 5 𝐴 ∈ V → (⟨𝐴, 𝑥⟩ ∈ 𝐹 → ∃𝑦((⟨𝐴, 𝑥⟩ ∈ 𝐹 ∧ ⟨𝐴, 𝑦⟩ ∈ 𝐹) ∧ ¬ 𝑥 = 𝑦)))
21 df-br 4578 . . . . 5 (𝐴𝐹𝑥 ↔ ⟨𝐴, 𝑥⟩ ∈ 𝐹)
22 df-br 4578 . . . . . . . 8 (𝐴𝐹𝑦 ↔ ⟨𝐴, 𝑦⟩ ∈ 𝐹)
2321, 22anbi12i 728 . . . . . . 7 ((𝐴𝐹𝑥𝐴𝐹𝑦) ↔ (⟨𝐴, 𝑥⟩ ∈ 𝐹 ∧ ⟨𝐴, 𝑦⟩ ∈ 𝐹))
2423anbi1i 726 . . . . . 6 (((𝐴𝐹𝑥𝐴𝐹𝑦) ∧ ¬ 𝑥 = 𝑦) ↔ ((⟨𝐴, 𝑥⟩ ∈ 𝐹 ∧ ⟨𝐴, 𝑦⟩ ∈ 𝐹) ∧ ¬ 𝑥 = 𝑦))
2524exbii 1763 . . . . 5 (∃𝑦((𝐴𝐹𝑥𝐴𝐹𝑦) ∧ ¬ 𝑥 = 𝑦) ↔ ∃𝑦((⟨𝐴, 𝑥⟩ ∈ 𝐹 ∧ ⟨𝐴, 𝑦⟩ ∈ 𝐹) ∧ ¬ 𝑥 = 𝑦))
2620, 21, 253imtr4g 283 . . . 4 𝐴 ∈ V → (𝐴𝐹𝑥 → ∃𝑦((𝐴𝐹𝑥𝐴𝐹𝑦) ∧ ¬ 𝑥 = 𝑦)))
2726eximdv 1832 . . 3 𝐴 ∈ V → (∃𝑥 𝐴𝐹𝑥 → ∃𝑥𝑦((𝐴𝐹𝑥𝐴𝐹𝑦) ∧ ¬ 𝑥 = 𝑦)))
28 exnal 1743 . . . 4 (∃𝑥 ¬ ∀𝑦((𝐴𝐹𝑥𝐴𝐹𝑦) → 𝑥 = 𝑦) ↔ ¬ ∀𝑥𝑦((𝐴𝐹𝑥𝐴𝐹𝑦) → 𝑥 = 𝑦))
29 exanali 1772 . . . . 5 (∃𝑦((𝐴𝐹𝑥𝐴𝐹𝑦) ∧ ¬ 𝑥 = 𝑦) ↔ ¬ ∀𝑦((𝐴𝐹𝑥𝐴𝐹𝑦) → 𝑥 = 𝑦))
3029exbii 1763 . . . 4 (∃𝑥𝑦((𝐴𝐹𝑥𝐴𝐹𝑦) ∧ ¬ 𝑥 = 𝑦) ↔ ∃𝑥 ¬ ∀𝑦((𝐴𝐹𝑥𝐴𝐹𝑦) → 𝑥 = 𝑦))
31 breq2 4581 . . . . . 6 (𝑥 = 𝑦 → (𝐴𝐹𝑥𝐴𝐹𝑦))
3231mo4 2504 . . . . 5 (∃*𝑥 𝐴𝐹𝑥 ↔ ∀𝑥𝑦((𝐴𝐹𝑥𝐴𝐹𝑦) → 𝑥 = 𝑦))
3332notbii 308 . . . 4 (¬ ∃*𝑥 𝐴𝐹𝑥 ↔ ¬ ∀𝑥𝑦((𝐴𝐹𝑥𝐴𝐹𝑦) → 𝑥 = 𝑦))
3428, 30, 333bitr4ri 291 . . 3 (¬ ∃*𝑥 𝐴𝐹𝑥 ↔ ∃𝑥𝑦((𝐴𝐹𝑥𝐴𝐹𝑦) ∧ ¬ 𝑥 = 𝑦))
3527, 34syl6ibr 240 . 2 𝐴 ∈ V → (∃𝑥 𝐴𝐹𝑥 → ¬ ∃*𝑥 𝐴𝐹𝑥))
36 eu5 2483 . . . 4 (∃!𝑥 𝐴𝐹𝑥 ↔ (∃𝑥 𝐴𝐹𝑥 ∧ ∃*𝑥 𝐴𝐹𝑥))
3736notbii 308 . . 3 (¬ ∃!𝑥 𝐴𝐹𝑥 ↔ ¬ (∃𝑥 𝐴𝐹𝑥 ∧ ∃*𝑥 𝐴𝐹𝑥))
38 imnan 436 . . 3 ((∃𝑥 𝐴𝐹𝑥 → ¬ ∃*𝑥 𝐴𝐹𝑥) ↔ ¬ (∃𝑥 𝐴𝐹𝑥 ∧ ∃*𝑥 𝐴𝐹𝑥))
3937, 38bitr4i 265 . 2 (¬ ∃!𝑥 𝐴𝐹𝑥 ↔ (∃𝑥 𝐴𝐹𝑥 → ¬ ∃*𝑥 𝐴𝐹𝑥))
4035, 39sylibr 222 1 𝐴 ∈ V → ¬ ∃!𝑥 𝐴𝐹𝑥)
Colors of variables: wff setvar class
Syntax hints:  ¬ wn 3  wi 4  wa 382  wal 1472  wex 1694  wcel 1976  ∃!weu 2457  ∃*wmo 2458  Vcvv 3172  c0 3873  cop 4130   class class class wbr 4577
This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1712  ax-4 1727  ax-5 1826  ax-6 1874  ax-7 1921  ax-8 1978  ax-9 1985  ax-10 2005  ax-11 2020  ax-12 2033  ax-13 2233  ax-ext 2589  ax-nul 4712  ax-pow 4764
This theorem depends on definitions:  df-bi 195  df-or 383  df-an 384  df-3an 1032  df-tru 1477  df-ex 1695  df-nf 1700  df-sb 1867  df-eu 2461  df-mo 2462  df-clab 2596  df-cleq 2602  df-clel 2605  df-nfc 2739  df-rab 2904  df-v 3174  df-dif 3542  df-un 3544  df-in 3546  df-ss 3553  df-nul 3874  df-if 4036  df-sn 4125  df-pr 4127  df-op 4131  df-br 4578
This theorem is referenced by:  fvprc  6082
  Copyright terms: Public domain W3C validator