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Theorem infiexmid 7065
Description: If the intersection of any finite set and any other set is finite, excluded middle follows. (Contributed by Jim Kingdon, 5-Feb-2022.)
Hypothesis
Ref Expression
infiexmid.1 (𝑥 ∈ Fin → (𝑥𝑦) ∈ Fin)
Assertion
Ref Expression
infiexmid (𝜑 ∨ ¬ 𝜑)
Distinct variable group:   𝜑,𝑥,𝑦

Proof of Theorem infiexmid
StepHypRef Expression
1 dfss1 3411 . . . . . 6 (𝑦𝑥 ↔ (𝑥𝑦) = 𝑦)
21biimpi 120 . . . . 5 (𝑦𝑥 → (𝑥𝑦) = 𝑦)
32adantl 277 . . . 4 ((𝑥 ∈ Fin ∧ 𝑦𝑥) → (𝑥𝑦) = 𝑦)
4 infiexmid.1 . . . . 5 (𝑥 ∈ Fin → (𝑥𝑦) ∈ Fin)
54adantr 276 . . . 4 ((𝑥 ∈ Fin ∧ 𝑦𝑥) → (𝑥𝑦) ∈ Fin)
63, 5eqeltrrd 2309 . . 3 ((𝑥 ∈ Fin ∧ 𝑦𝑥) → 𝑦 ∈ Fin)
76gen2 1498 . 2 𝑥𝑦((𝑥 ∈ Fin ∧ 𝑦𝑥) → 𝑦 ∈ Fin)
87ssfiexmid 7062 1 (𝜑 ∨ ¬ 𝜑)
Colors of variables: wff set class
Syntax hints:  ¬ wn 3  wi 4  wa 104  wo 715   = wceq 1397  wcel 2202  cin 3199  wss 3200  Fincfn 6908
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 619  ax-in2 620  ax-io 716  ax-5 1495  ax-7 1496  ax-gen 1497  ax-ie1 1541  ax-ie2 1542  ax-8 1552  ax-10 1553  ax-11 1554  ax-i12 1555  ax-bndl 1557  ax-4 1558  ax-17 1574  ax-i9 1578  ax-ial 1582  ax-i5r 1583  ax-13 2204  ax-14 2205  ax-ext 2213  ax-sep 4207  ax-nul 4215  ax-pow 4264  ax-pr 4299  ax-un 4530  ax-iinf 4686
This theorem depends on definitions:  df-bi 117  df-3an 1006  df-tru 1400  df-fal 1403  df-nf 1509  df-sb 1811  df-eu 2082  df-mo 2083  df-clab 2218  df-cleq 2224  df-clel 2227  df-nfc 2363  df-ral 2515  df-rex 2516  df-rab 2519  df-v 2804  df-sbc 3032  df-dif 3202  df-un 3204  df-in 3206  df-ss 3213  df-nul 3495  df-pw 3654  df-sn 3675  df-pr 3676  df-op 3678  df-uni 3894  df-int 3929  df-br 4089  df-opab 4151  df-id 4390  df-suc 4468  df-iom 4689  df-xp 4731  df-rel 4732  df-cnv 4733  df-co 4734  df-dm 4735  df-rn 4736  df-res 4737  df-ima 4738  df-iota 5286  df-fun 5328  df-fn 5329  df-f 5330  df-f1 5331  df-fo 5332  df-f1o 5333  df-fv 5334  df-1o 6581  df-er 6701  df-en 6909  df-fin 6911
This theorem is referenced by: (None)
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