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Theorem omsinds 4623
Description: Strong (or "total") induction principle over ω. (Contributed by Scott Fenton, 17-Jul-2015.)
Hypotheses
Ref Expression
omsinds.1 (𝑥 = 𝑦 → (𝜑𝜓))
omsinds.2 (𝑥 = 𝐴 → (𝜑𝜒))
omsinds.3 (𝑥 ∈ ω → (∀𝑦𝑥 𝜓𝜑))
Assertion
Ref Expression
omsinds (𝐴 ∈ ω → 𝜒)
Distinct variable groups:   𝑥,𝐴   𝜒,𝑥   𝜑,𝑦   𝜓,𝑥   𝑥,𝑦
Allowed substitution hints:   𝜑(𝑥)   𝜓(𝑦)   𝜒(𝑦)   𝐴(𝑦)

Proof of Theorem omsinds
Dummy variables 𝑤 𝑘 are mutually distinct and distinct from all other variables.
StepHypRef Expression
1 omsinds.2 . 2 (𝑥 = 𝐴 → (𝜑𝜒))
2 suceq 4404 . . . 4 (𝑤 = ∅ → suc 𝑤 = suc ∅)
32raleqdv 2679 . . 3 (𝑤 = ∅ → (∀𝑥 ∈ suc 𝑤𝜑 ↔ ∀𝑥 ∈ suc ∅𝜑))
4 suceq 4404 . . . 4 (𝑤 = 𝑘 → suc 𝑤 = suc 𝑘)
54raleqdv 2679 . . 3 (𝑤 = 𝑘 → (∀𝑥 ∈ suc 𝑤𝜑 ↔ ∀𝑥 ∈ suc 𝑘𝜑))
6 suceq 4404 . . . 4 (𝑤 = suc 𝑘 → suc 𝑤 = suc suc 𝑘)
76raleqdv 2679 . . 3 (𝑤 = suc 𝑘 → (∀𝑥 ∈ suc 𝑤𝜑 ↔ ∀𝑥 ∈ suc suc 𝑘𝜑))
8 suceq 4404 . . . 4 (𝑤 = 𝐴 → suc 𝑤 = suc 𝐴)
98raleqdv 2679 . . 3 (𝑤 = 𝐴 → (∀𝑥 ∈ suc 𝑤𝜑 ↔ ∀𝑥 ∈ suc 𝐴𝜑))
10 ral0 3526 . . . . . 6 𝑦 ∈ ∅ 𝜓
11 omsinds.3 . . . . . . . 8 (𝑥 ∈ ω → (∀𝑦𝑥 𝜓𝜑))
1211rgen 2530 . . . . . . 7 𝑥 ∈ ω (∀𝑦𝑥 𝜓𝜑)
13 peano1 4595 . . . . . . . 8 ∅ ∈ ω
1410nfth 1464 . . . . . . . . . 10 𝑥𝑦 ∈ ∅ 𝜓
15 nfsbc1v 2983 . . . . . . . . . 10 𝑥[∅ / 𝑥]𝜑
1614, 15nfim 1572 . . . . . . . . 9 𝑥(∀𝑦 ∈ ∅ 𝜓[∅ / 𝑥]𝜑)
17 raleq 2673 . . . . . . . . . 10 (𝑥 = ∅ → (∀𝑦𝑥 𝜓 ↔ ∀𝑦 ∈ ∅ 𝜓))
18 sbceq1a 2974 . . . . . . . . . 10 (𝑥 = ∅ → (𝜑[∅ / 𝑥]𝜑))
1917, 18imbi12d 234 . . . . . . . . 9 (𝑥 = ∅ → ((∀𝑦𝑥 𝜓𝜑) ↔ (∀𝑦 ∈ ∅ 𝜓[∅ / 𝑥]𝜑)))
2016, 19rspc 2837 . . . . . . . 8 (∅ ∈ ω → (∀𝑥 ∈ ω (∀𝑦𝑥 𝜓𝜑) → (∀𝑦 ∈ ∅ 𝜓[∅ / 𝑥]𝜑)))
2113, 20ax-mp 5 . . . . . . 7 (∀𝑥 ∈ ω (∀𝑦𝑥 𝜓𝜑) → (∀𝑦 ∈ ∅ 𝜓[∅ / 𝑥]𝜑))
2212, 21ax-mp 5 . . . . . 6 (∀𝑦 ∈ ∅ 𝜓[∅ / 𝑥]𝜑)
2310, 22ax-mp 5 . . . . 5 [∅ / 𝑥]𝜑
24 ralsns 3632 . . . . . 6 (∅ ∈ ω → (∀𝑥 ∈ {∅}𝜑[∅ / 𝑥]𝜑))
2513, 24ax-mp 5 . . . . 5 (∀𝑥 ∈ {∅}𝜑[∅ / 𝑥]𝜑)
2623, 25mpbir 146 . . . 4 𝑥 ∈ {∅}𝜑
27 suc0 4413 . . . . 5 suc ∅ = {∅}
2827raleqi 2677 . . . 4 (∀𝑥 ∈ suc ∅𝜑 ↔ ∀𝑥 ∈ {∅}𝜑)
2926, 28mpbir 146 . . 3 𝑥 ∈ suc ∅𝜑
30 simpr 110 . . . . . 6 ((𝑘 ∈ ω ∧ ∀𝑥 ∈ suc 𝑘𝜑) → ∀𝑥 ∈ suc 𝑘𝜑)
31 peano2 4596 . . . . . . . . 9 (𝑘 ∈ ω → suc 𝑘 ∈ ω)
3231adantr 276 . . . . . . . 8 ((𝑘 ∈ ω ∧ ∀𝑥 ∈ suc 𝑘𝜑) → suc 𝑘 ∈ ω)
33 omsinds.1 . . . . . . . . . 10 (𝑥 = 𝑦 → (𝜑𝜓))
3433cbvralv 2705 . . . . . . . . 9 (∀𝑥 ∈ suc 𝑘𝜑 ↔ ∀𝑦 ∈ suc 𝑘𝜓)
3530, 34sylib 122 . . . . . . . 8 ((𝑘 ∈ ω ∧ ∀𝑥 ∈ suc 𝑘𝜑) → ∀𝑦 ∈ suc 𝑘𝜓)
36 nfv 1528 . . . . . . . . . . 11 𝑥𝑦 ∈ suc 𝑘𝜓
37 nfsbc1v 2983 . . . . . . . . . . 11 𝑥[suc 𝑘 / 𝑥]𝜑
3836, 37nfim 1572 . . . . . . . . . 10 𝑥(∀𝑦 ∈ suc 𝑘𝜓[suc 𝑘 / 𝑥]𝜑)
39 raleq 2673 . . . . . . . . . . 11 (𝑥 = suc 𝑘 → (∀𝑦𝑥 𝜓 ↔ ∀𝑦 ∈ suc 𝑘𝜓))
40 sbceq1a 2974 . . . . . . . . . . 11 (𝑥 = suc 𝑘 → (𝜑[suc 𝑘 / 𝑥]𝜑))
4139, 40imbi12d 234 . . . . . . . . . 10 (𝑥 = suc 𝑘 → ((∀𝑦𝑥 𝜓𝜑) ↔ (∀𝑦 ∈ suc 𝑘𝜓[suc 𝑘 / 𝑥]𝜑)))
4238, 41rspc 2837 . . . . . . . . 9 (suc 𝑘 ∈ ω → (∀𝑥 ∈ ω (∀𝑦𝑥 𝜓𝜑) → (∀𝑦 ∈ suc 𝑘𝜓[suc 𝑘 / 𝑥]𝜑)))
4312, 42mpi 15 . . . . . . . 8 (suc 𝑘 ∈ ω → (∀𝑦 ∈ suc 𝑘𝜓[suc 𝑘 / 𝑥]𝜑))
4432, 35, 43sylc 62 . . . . . . 7 ((𝑘 ∈ ω ∧ ∀𝑥 ∈ suc 𝑘𝜑) → [suc 𝑘 / 𝑥]𝜑)
45 ralsns 3632 . . . . . . . 8 (suc 𝑘 ∈ ω → (∀𝑥 ∈ {suc 𝑘}𝜑[suc 𝑘 / 𝑥]𝜑))
4632, 45syl 14 . . . . . . 7 ((𝑘 ∈ ω ∧ ∀𝑥 ∈ suc 𝑘𝜑) → (∀𝑥 ∈ {suc 𝑘}𝜑[suc 𝑘 / 𝑥]𝜑))
4744, 46mpbird 167 . . . . . 6 ((𝑘 ∈ ω ∧ ∀𝑥 ∈ suc 𝑘𝜑) → ∀𝑥 ∈ {suc 𝑘}𝜑)
48 ralun 3319 . . . . . 6 ((∀𝑥 ∈ suc 𝑘𝜑 ∧ ∀𝑥 ∈ {suc 𝑘}𝜑) → ∀𝑥 ∈ (suc 𝑘 ∪ {suc 𝑘})𝜑)
4930, 47, 48syl2anc 411 . . . . 5 ((𝑘 ∈ ω ∧ ∀𝑥 ∈ suc 𝑘𝜑) → ∀𝑥 ∈ (suc 𝑘 ∪ {suc 𝑘})𝜑)
50 df-suc 4373 . . . . . . 7 suc suc 𝑘 = (suc 𝑘 ∪ {suc 𝑘})
5150a1i 9 . . . . . 6 ((𝑘 ∈ ω ∧ ∀𝑥 ∈ suc 𝑘𝜑) → suc suc 𝑘 = (suc 𝑘 ∪ {suc 𝑘}))
5251raleqdv 2679 . . . . 5 ((𝑘 ∈ ω ∧ ∀𝑥 ∈ suc 𝑘𝜑) → (∀𝑥 ∈ suc suc 𝑘𝜑 ↔ ∀𝑥 ∈ (suc 𝑘 ∪ {suc 𝑘})𝜑))
5349, 52mpbird 167 . . . 4 ((𝑘 ∈ ω ∧ ∀𝑥 ∈ suc 𝑘𝜑) → ∀𝑥 ∈ suc suc 𝑘𝜑)
5453ex 115 . . 3 (𝑘 ∈ ω → (∀𝑥 ∈ suc 𝑘𝜑 → ∀𝑥 ∈ suc suc 𝑘𝜑))
553, 5, 7, 9, 29, 54finds 4601 . 2 (𝐴 ∈ ω → ∀𝑥 ∈ suc 𝐴𝜑)
56 sucidg 4418 . 2 (𝐴 ∈ ω → 𝐴 ∈ suc 𝐴)
571, 55, 56rspcdva 2848 1 (𝐴 ∈ ω → 𝜒)
Colors of variables: wff set class
Syntax hints:  wi 4  wa 104  wb 105   = wceq 1353  wcel 2148  wral 2455  [wsbc 2964  cun 3129  c0 3424  {csn 3594  suc csuc 4367  ωcom 4591
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 614  ax-in2 615  ax-io 709  ax-5 1447  ax-7 1448  ax-gen 1449  ax-ie1 1493  ax-ie2 1494  ax-8 1504  ax-10 1505  ax-11 1506  ax-i12 1507  ax-bndl 1509  ax-4 1510  ax-17 1526  ax-i9 1530  ax-ial 1534  ax-i5r 1535  ax-13 2150  ax-14 2151  ax-ext 2159  ax-sep 4123  ax-nul 4131  ax-pow 4176  ax-pr 4211  ax-un 4435  ax-iinf 4589
This theorem depends on definitions:  df-bi 117  df-3an 980  df-tru 1356  df-nf 1461  df-sb 1763  df-clab 2164  df-cleq 2170  df-clel 2173  df-nfc 2308  df-ral 2460  df-rex 2461  df-v 2741  df-sbc 2965  df-dif 3133  df-un 3135  df-in 3137  df-ss 3144  df-nul 3425  df-pw 3579  df-sn 3600  df-pr 3601  df-uni 3812  df-int 3847  df-suc 4373  df-iom 4592
This theorem is referenced by:  nninfalllem1  14796  nninfsellemqall  14803
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