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Theorem tfis3 4309
 Description: Transfinite Induction Schema, using implicit substitution. (Contributed by NM, 4-Nov-2003.)
Hypotheses
Ref Expression
tfis3.1 (𝑥 = 𝑦 → (𝜑𝜓))
tfis3.2 (𝑥 = 𝐴 → (𝜑𝜒))
tfis3.3 (𝑥 ∈ On → (∀𝑦𝑥 𝜓𝜑))
Assertion
Ref Expression
tfis3 (𝐴 ∈ On → 𝜒)
Distinct variable groups:   𝜓,𝑥   𝜑,𝑦   𝜒,𝑥   𝑥,𝐴   𝑥,𝑦
Allowed substitution hints:   𝜑(𝑥)   𝜓(𝑦)   𝜒(𝑦)   𝐴(𝑦)

Proof of Theorem tfis3
StepHypRef Expression
1 tfis3.2 . 2 (𝑥 = 𝐴 → (𝜑𝜒))
2 tfis3.1 . . 3 (𝑥 = 𝑦 → (𝜑𝜓))
3 tfis3.3 . . 3 (𝑥 ∈ On → (∀𝑦𝑥 𝜓𝜑))
42, 3tfis2 4308 . 2 (𝑥 ∈ On → 𝜑)
51, 4vtoclga 2619 1 (𝐴 ∈ On → 𝜒)
 Colors of variables: wff set class Syntax hints:   → wi 4   ↔ wb 98   = wceq 1243   ∈ wcel 1393  ∀wral 2306  Oncon0 4100 This theorem was proved from axioms:  ax-1 5  ax-2 6  ax-mp 7  ax-ia1 99  ax-ia2 100  ax-ia3 101  ax-io 630  ax-5 1336  ax-7 1337  ax-gen 1338  ax-ie1 1382  ax-ie2 1383  ax-8 1395  ax-10 1396  ax-11 1397  ax-i12 1398  ax-bndl 1399  ax-4 1400  ax-17 1419  ax-i9 1423  ax-ial 1427  ax-i5r 1428  ax-ext 2022  ax-setind 4262 This theorem depends on definitions:  df-bi 110  df-3an 887  df-tru 1246  df-nf 1350  df-sb 1646  df-clab 2027  df-cleq 2033  df-clel 2036  df-nfc 2167  df-ral 2311  df-rex 2312  df-rab 2315  df-v 2559  df-in 2924  df-ss 2931  df-uni 3581  df-tr 3855  df-iord 4103  df-on 4105 This theorem is referenced by:  tfisi  4310  tfrlemi1  5946  rdgon  5973
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