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Theorem inffiexmid 7064
Description: If any given set is either finite or infinite, excluded middle follows. (Contributed by Jim Kingdon, 15-Jun-2022.)
Hypothesis
Ref Expression
inffiexmid.1 (𝑥 ∈ Fin ∨ ω ≼ 𝑥)
Assertion
Ref Expression
inffiexmid (𝜑 ∨ ¬ 𝜑)
Distinct variable group:   𝜑,𝑥

Proof of Theorem inffiexmid
Dummy variables 𝑦 𝑧 are mutually distinct and distinct from all other variables.
StepHypRef Expression
1 omex 4684 . . . . 5 ω ∈ V
21rabex 4227 . . . 4 {𝑦 ∈ ω ∣ 𝜑} ∈ V
3 eleq1 2292 . . . . 5 (𝑥 = {𝑦 ∈ ω ∣ 𝜑} → (𝑥 ∈ Fin ↔ {𝑦 ∈ ω ∣ 𝜑} ∈ Fin))
4 breq2 4086 . . . . 5 (𝑥 = {𝑦 ∈ ω ∣ 𝜑} → (ω ≼ 𝑥 ↔ ω ≼ {𝑦 ∈ ω ∣ 𝜑}))
53, 4orbi12d 798 . . . 4 (𝑥 = {𝑦 ∈ ω ∣ 𝜑} → ((𝑥 ∈ Fin ∨ ω ≼ 𝑥) ↔ ({𝑦 ∈ ω ∣ 𝜑} ∈ Fin ∨ ω ≼ {𝑦 ∈ ω ∣ 𝜑})))
6 inffiexmid.1 . . . 4 (𝑥 ∈ Fin ∨ ω ≼ 𝑥)
72, 5, 6vtocl 2855 . . 3 ({𝑦 ∈ ω ∣ 𝜑} ∈ Fin ∨ ω ≼ {𝑦 ∈ ω ∣ 𝜑})
8 ominf 7054 . . . . . 6 ¬ ω ∈ Fin
9 peano1 4685 . . . . . . . . . 10 ∅ ∈ ω
10 elex2 2816 . . . . . . . . . 10 (∅ ∈ ω → ∃𝑤 𝑤 ∈ ω)
119, 10ax-mp 5 . . . . . . . . 9 𝑤 𝑤 ∈ ω
12 r19.3rmv 3582 . . . . . . . . 9 (∃𝑤 𝑤 ∈ ω → (𝜑 ↔ ∀𝑦 ∈ ω 𝜑))
1311, 12ax-mp 5 . . . . . . . 8 (𝜑 ↔ ∀𝑦 ∈ ω 𝜑)
14 rabid2 2708 . . . . . . . 8 (ω = {𝑦 ∈ ω ∣ 𝜑} ↔ ∀𝑦 ∈ ω 𝜑)
1513, 14sylbb2 138 . . . . . . 7 (𝜑 → ω = {𝑦 ∈ ω ∣ 𝜑})
1615eleq1d 2298 . . . . . 6 (𝜑 → (ω ∈ Fin ↔ {𝑦 ∈ ω ∣ 𝜑} ∈ Fin))
178, 16mtbii 678 . . . . 5 (𝜑 → ¬ {𝑦 ∈ ω ∣ 𝜑} ∈ Fin)
1817con2i 630 . . . 4 ({𝑦 ∈ ω ∣ 𝜑} ∈ Fin → ¬ 𝜑)
19 infm 7062 . . . . 5 (ω ≼ {𝑦 ∈ ω ∣ 𝜑} → ∃𝑧 𝑧 ∈ {𝑦 ∈ ω ∣ 𝜑})
20 biidd 172 . . . . . . . 8 (𝑦 = 𝑧 → (𝜑𝜑))
2120elrab 2959 . . . . . . 7 (𝑧 ∈ {𝑦 ∈ ω ∣ 𝜑} ↔ (𝑧 ∈ ω ∧ 𝜑))
2221simprbi 275 . . . . . 6 (𝑧 ∈ {𝑦 ∈ ω ∣ 𝜑} → 𝜑)
2322exlimiv 1644 . . . . 5 (∃𝑧 𝑧 ∈ {𝑦 ∈ ω ∣ 𝜑} → 𝜑)
2419, 23syl 14 . . . 4 (ω ≼ {𝑦 ∈ ω ∣ 𝜑} → 𝜑)
2518, 24orim12i 764 . . 3 (({𝑦 ∈ ω ∣ 𝜑} ∈ Fin ∨ ω ≼ {𝑦 ∈ ω ∣ 𝜑}) → (¬ 𝜑𝜑))
267, 25ax-mp 5 . 2 𝜑𝜑)
27 orcom 733 . 2 ((¬ 𝜑𝜑) ↔ (𝜑 ∨ ¬ 𝜑))
2826, 27mpbi 145 1 (𝜑 ∨ ¬ 𝜑)
Colors of variables: wff set class
Syntax hints:  ¬ wn 3  wb 105  wo 713   = wceq 1395  wex 1538  wcel 2200  wral 2508  {crab 2512  c0 3491   class class class wbr 4082  ωcom 4681  cdom 6884  Fincfn 6885
This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 106  ax-ia2 107  ax-ia3 108  ax-in1 617  ax-in2 618  ax-io 714  ax-5 1493  ax-7 1494  ax-gen 1495  ax-ie1 1539  ax-ie2 1540  ax-8 1550  ax-10 1551  ax-11 1552  ax-i12 1553  ax-bndl 1555  ax-4 1556  ax-17 1572  ax-i9 1576  ax-ial 1580  ax-i5r 1581  ax-13 2202  ax-14 2203  ax-ext 2211  ax-sep 4201  ax-nul 4209  ax-pow 4257  ax-pr 4292  ax-un 4523  ax-setind 4628  ax-iinf 4679
This theorem depends on definitions:  df-bi 117  df-dc 840  df-3or 1003  df-3an 1004  df-tru 1398  df-fal 1401  df-nf 1507  df-sb 1809  df-eu 2080  df-mo 2081  df-clab 2216  df-cleq 2222  df-clel 2225  df-nfc 2361  df-ne 2401  df-ral 2513  df-rex 2514  df-rab 2517  df-v 2801  df-sbc 3029  df-dif 3199  df-un 3201  df-in 3203  df-ss 3210  df-nul 3492  df-pw 3651  df-sn 3672  df-pr 3673  df-op 3675  df-uni 3888  df-int 3923  df-br 4083  df-opab 4145  df-tr 4182  df-id 4383  df-iord 4456  df-on 4458  df-suc 4461  df-iom 4682  df-xp 4724  df-rel 4725  df-cnv 4726  df-co 4727  df-dm 4728  df-rn 4729  df-res 4730  df-ima 4731  df-iota 5277  df-fun 5319  df-fn 5320  df-f 5321  df-f1 5322  df-fo 5323  df-f1o 5324  df-fv 5325  df-er 6678  df-en 6886  df-dom 6887  df-fin 6888
This theorem is referenced by: (None)
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