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Theorem oawordriexmid 6579
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 6578. (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 6532 . . . . 5 1o ∈ On
2 oawordriexmid.1 . . . . . . . 8 ((𝑎 ∈ On ∧ 𝑏 ∈ On ∧ 𝑐 ∈ On) → (𝑎𝑏 → (𝑎 +o 𝑐) ⊆ (𝑏 +o 𝑐)))
323expa 1206 . . . . . . 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 2561 . . . . 5 𝑐 ∈ On ((𝑎 ∈ On ∧ 𝑏 ∈ On) → (𝑎𝑏 → (𝑎 +o 𝑐) ⊆ (𝑏 +o 𝑐)))
6 oveq2 5975 . . . . . . . . 9 (𝑐 = 1o → (𝑎 +o 𝑐) = (𝑎 +o 1o))
7 oveq2 5975 . . . . . . . . 9 (𝑐 = 1o → (𝑏 +o 𝑐) = (𝑏 +o 1o))
86, 7sseq12d 3232 . . . . . . . 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 2880 . . . . 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 6576 . . . . . 6 (𝑎 ∈ On → (𝑎 +o 1o) = suc 𝑎)
1413adantr 276 . . . . 5 ((𝑎 ∈ On ∧ 𝑏 ∈ On) → (𝑎 +o 1o) = suc 𝑎)
15 oa1suc 6576 . . . . . 6 (𝑏 ∈ On → (𝑏 +o 1o) = suc 𝑏)
1615adantl 277 . . . . 5 ((𝑎 ∈ On ∧ 𝑏 ∈ On) → (𝑏 +o 1o) = suc 𝑏)
1714, 16sseq12d 3232 . . . 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 2562 . 2 𝑎 ∈ On ∀𝑏 ∈ On (𝑎𝑏 → suc 𝑎 ⊆ suc 𝑏)
2019onsucsssucexmid 4593 1 (𝜑 ∨ ¬ 𝜑)
Colors of variables: wff set class
Syntax hints:  ¬ wn 3  wi 4  wa 104  wo 710  w3a 981   = wceq 1373  wcel 2178  wral 2486  wss 3174  Oncon0 4428  suc csuc 4430  (class class class)co 5967  1oc1o 6518   +o coa 6522
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 711  ax-5 1471  ax-7 1472  ax-gen 1473  ax-ie1 1517  ax-ie2 1518  ax-8 1528  ax-10 1529  ax-11 1530  ax-i12 1531  ax-bndl 1533  ax-4 1534  ax-17 1550  ax-i9 1554  ax-ial 1558  ax-i5r 1559  ax-13 2180  ax-14 2181  ax-ext 2189  ax-coll 4175  ax-sep 4178  ax-nul 4186  ax-pow 4234  ax-pr 4269  ax-un 4498  ax-setind 4603  ax-iinf 4654
This theorem depends on definitions:  df-bi 117  df-3an 983  df-tru 1376  df-fal 1379  df-nf 1485  df-sb 1787  df-eu 2058  df-mo 2059  df-clab 2194  df-cleq 2200  df-clel 2203  df-nfc 2339  df-ne 2379  df-ral 2491  df-rex 2492  df-reu 2493  df-rab 2495  df-v 2778  df-sbc 3006  df-csb 3102  df-dif 3176  df-un 3178  df-in 3180  df-ss 3187  df-nul 3469  df-pw 3628  df-sn 3649  df-pr 3650  df-op 3652  df-uni 3865  df-int 3900  df-iun 3943  df-br 4060  df-opab 4122  df-mpt 4123  df-tr 4159  df-id 4358  df-iord 4431  df-on 4433  df-suc 4436  df-iom 4657  df-xp 4699  df-rel 4700  df-cnv 4701  df-co 4702  df-dm 4703  df-rn 4704  df-res 4705  df-ima 4706  df-iota 5251  df-fun 5292  df-fn 5293  df-f 5294  df-f1 5295  df-fo 5296  df-f1o 5297  df-fv 5298  df-ov 5970  df-oprab 5971  df-mpo 5972  df-1st 6249  df-2nd 6250  df-recs 6414  df-irdg 6479  df-1o 6525  df-oadd 6529
This theorem is referenced by: (None)
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