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Theorem oawordriexmid 6555
Description: A weak ordering property of ordinal addition which implies excluded middle. The property is proposition 8.7 of [TakeutiZaring] p. 59. Compare with oawordi 6554. (Contributed by Jim Kingdon, 15-May-2022.)
Hypothesis
Ref Expression
oawordriexmid.1 ((𝑎 ∈ On ∧ 𝑏 ∈ On ∧ 𝑐 ∈ On) → (𝑎𝑏 → (𝑎 +o 𝑐) ⊆ (𝑏 +o 𝑐)))
Assertion
Ref Expression
oawordriexmid (𝜑 ∨ ¬ 𝜑)
Distinct variable groups:   𝑎,𝑏,𝑐   𝜑,𝑎
Allowed substitution hints:   𝜑(𝑏,𝑐)

Proof of Theorem oawordriexmid
StepHypRef Expression
1 1on 6508 . . . . 5 1o ∈ On
2 oawordriexmid.1 . . . . . . . 8 ((𝑎 ∈ On ∧ 𝑏 ∈ On ∧ 𝑐 ∈ On) → (𝑎𝑏 → (𝑎 +o 𝑐) ⊆ (𝑏 +o 𝑐)))
323expa 1205 . . . . . . 7 (((𝑎 ∈ On ∧ 𝑏 ∈ On) ∧ 𝑐 ∈ On) → (𝑎𝑏 → (𝑎 +o 𝑐) ⊆ (𝑏 +o 𝑐)))
43expcom 116 . . . . . 6 (𝑐 ∈ On → ((𝑎 ∈ On ∧ 𝑏 ∈ On) → (𝑎𝑏 → (𝑎 +o 𝑐) ⊆ (𝑏 +o 𝑐))))
54rgen 2558 . . . . 5 𝑐 ∈ On ((𝑎 ∈ On ∧ 𝑏 ∈ On) → (𝑎𝑏 → (𝑎 +o 𝑐) ⊆ (𝑏 +o 𝑐)))
6 oveq2 5951 . . . . . . . . 9 (𝑐 = 1o → (𝑎 +o 𝑐) = (𝑎 +o 1o))
7 oveq2 5951 . . . . . . . . 9 (𝑐 = 1o → (𝑏 +o 𝑐) = (𝑏 +o 1o))
86, 7sseq12d 3223 . . . . . . . 8 (𝑐 = 1o → ((𝑎 +o 𝑐) ⊆ (𝑏 +o 𝑐) ↔ (𝑎 +o 1o) ⊆ (𝑏 +o 1o)))
98imbi2d 230 . . . . . . 7 (𝑐 = 1o → ((𝑎𝑏 → (𝑎 +o 𝑐) ⊆ (𝑏 +o 𝑐)) ↔ (𝑎𝑏 → (𝑎 +o 1o) ⊆ (𝑏 +o 1o))))
109imbi2d 230 . . . . . 6 (𝑐 = 1o → (((𝑎 ∈ On ∧ 𝑏 ∈ On) → (𝑎𝑏 → (𝑎 +o 𝑐) ⊆ (𝑏 +o 𝑐))) ↔ ((𝑎 ∈ On ∧ 𝑏 ∈ On) → (𝑎𝑏 → (𝑎 +o 1o) ⊆ (𝑏 +o 1o)))))
1110rspcv 2872 . . . . 5 (1o ∈ On → (∀𝑐 ∈ On ((𝑎 ∈ On ∧ 𝑏 ∈ On) → (𝑎𝑏 → (𝑎 +o 𝑐) ⊆ (𝑏 +o 𝑐))) → ((𝑎 ∈ On ∧ 𝑏 ∈ On) → (𝑎𝑏 → (𝑎 +o 1o) ⊆ (𝑏 +o 1o)))))
121, 5, 11mp2 16 . . . 4 ((𝑎 ∈ On ∧ 𝑏 ∈ On) → (𝑎𝑏 → (𝑎 +o 1o) ⊆ (𝑏 +o 1o)))
13 oa1suc 6552 . . . . . 6 (𝑎 ∈ On → (𝑎 +o 1o) = suc 𝑎)
1413adantr 276 . . . . 5 ((𝑎 ∈ On ∧ 𝑏 ∈ On) → (𝑎 +o 1o) = suc 𝑎)
15 oa1suc 6552 . . . . . 6 (𝑏 ∈ On → (𝑏 +o 1o) = suc 𝑏)
1615adantl 277 . . . . 5 ((𝑎 ∈ On ∧ 𝑏 ∈ On) → (𝑏 +o 1o) = suc 𝑏)
1714, 16sseq12d 3223 . . . 4 ((𝑎 ∈ On ∧ 𝑏 ∈ On) → ((𝑎 +o 1o) ⊆ (𝑏 +o 1o) ↔ suc 𝑎 ⊆ suc 𝑏))
1812, 17sylibd 149 . . 3 ((𝑎 ∈ On ∧ 𝑏 ∈ On) → (𝑎𝑏 → suc 𝑎 ⊆ suc 𝑏))
1918rgen2a 2559 . 2 𝑎 ∈ On ∀𝑏 ∈ On (𝑎𝑏 → suc 𝑎 ⊆ suc 𝑏)
2019onsucsssucexmid 4574 1 (𝜑 ∨ ¬ 𝜑)
Colors of variables: wff set class
Syntax hints:  ¬ wn 3  wi 4  wa 104  wo 709  w3a 980   = wceq 1372  wcel 2175  wral 2483  wss 3165  Oncon0 4409  suc csuc 4411  (class class class)co 5943  1oc1o 6494   +o coa 6498
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 615  ax-in2 616  ax-io 710  ax-5 1469  ax-7 1470  ax-gen 1471  ax-ie1 1515  ax-ie2 1516  ax-8 1526  ax-10 1527  ax-11 1528  ax-i12 1529  ax-bndl 1531  ax-4 1532  ax-17 1548  ax-i9 1552  ax-ial 1556  ax-i5r 1557  ax-13 2177  ax-14 2178  ax-ext 2186  ax-coll 4158  ax-sep 4161  ax-nul 4169  ax-pow 4217  ax-pr 4252  ax-un 4479  ax-setind 4584  ax-iinf 4635
This theorem depends on definitions:  df-bi 117  df-3an 982  df-tru 1375  df-fal 1378  df-nf 1483  df-sb 1785  df-eu 2056  df-mo 2057  df-clab 2191  df-cleq 2197  df-clel 2200  df-nfc 2336  df-ne 2376  df-ral 2488  df-rex 2489  df-reu 2490  df-rab 2492  df-v 2773  df-sbc 2998  df-csb 3093  df-dif 3167  df-un 3169  df-in 3171  df-ss 3178  df-nul 3460  df-pw 3617  df-sn 3638  df-pr 3639  df-op 3641  df-uni 3850  df-int 3885  df-iun 3928  df-br 4044  df-opab 4105  df-mpt 4106  df-tr 4142  df-id 4339  df-iord 4412  df-on 4414  df-suc 4417  df-iom 4638  df-xp 4680  df-rel 4681  df-cnv 4682  df-co 4683  df-dm 4684  df-rn 4685  df-res 4686  df-ima 4687  df-iota 5231  df-fun 5272  df-fn 5273  df-f 5274  df-f1 5275  df-fo 5276  df-f1o 5277  df-fv 5278  df-ov 5946  df-oprab 5947  df-mpo 5948  df-1st 6225  df-2nd 6226  df-recs 6390  df-irdg 6455  df-1o 6501  df-oadd 6505
This theorem is referenced by: (None)
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