Theorem wfis3 5759

Description: Well Founded Induction schema, using implicit substitution. (Contributed by Scott Fenton, 29-Jan-2011.)

Hypotheses

Ref	Expression
wfis3.1	⊢ 𝑅 We 𝐴
wfis3.2	⊢ 𝑅 Se 𝐴
wfis3.3	⊢ (𝑦 = 𝑧 → (𝜑 ↔ 𝜓))
wfis3.4	⊢ (𝑦 = 𝐵 → (𝜑 ↔ 𝜒))
wfis3.5	⊢ (𝑦 ∈ 𝐴 → (∀𝑧 ∈ Pred (𝑅, 𝐴, 𝑦)𝜓 → 𝜑))

Assertion

Ref	Expression
wfis3	⊢ (𝐵 ∈ 𝐴 → 𝜒)

Distinct variable groups:   𝑦,𝐴,𝑧   𝑦,𝐵   𝜒,𝑦   𝜑,𝑧   𝜓,𝑦   𝑦,𝑅,𝑧

Allowed substitution hints:   𝜑(𝑦)   𝜓(𝑧)   𝜒(𝑧)   𝐵(𝑧)

Proof of Theorem wfis3

Step	Hyp	Ref	Expression
1		wfis3.4	. 2 ⊢ (𝑦 = 𝐵 → (𝜑 ↔ 𝜒))
2		wfis3.1	. . 3 ⊢ 𝑅 We 𝐴
3		wfis3.2	. . 3 ⊢ 𝑅 Se 𝐴
4		wfis3.3	. . 3 ⊢ (𝑦 = 𝑧 → (𝜑 ↔ 𝜓))
5		wfis3.5	. . 3 ⊢ (𝑦 ∈ 𝐴 → (∀𝑧 ∈ Pred (𝑅, 𝐴, 𝑦)𝜓 → 𝜑))
6	2, 3, 4, 5	wfis2 5758	. 2 ⊢ (𝑦 ∈ 𝐴 → 𝜑)
7	1, 6	vtoclga 3303	1 ⊢ (𝐵 ∈ 𝐴 → 𝜒)

Syntax hints:   → wi 4   ↔ wb 196   = wceq 1523   ∈ wcel 2030  ∀wral 2941   Se wse 5100   We wwe 5101  Predcpred 5717

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1762  ax-4 1777  ax-5 1879  ax-6 1945  ax-7 1981  ax-9 2039  ax-10 2059  ax-11 2074  ax-12 2087  ax-13 2282  ax-ext 2631  ax-sep 4814  ax-nul 4822  ax-pr 4936

This theorem depends on definitions:  df-bi 197  df-or 384  df-an 385  df-3or 1055  df-3an 1056  df-tru 1526  df-ex 1745  df-nf 1750  df-sb 1938  df-eu 2502  df-mo 2503  df-clab 2638  df-cleq 2644  df-clel 2647  df-nfc 2782  df-ne 2824  df-ral 2946  df-rex 2947  df-reu 2948  df-rmo 2949  df-rab 2950  df-v 3233  df-sbc 3469  df-dif 3610  df-un 3612  df-in 3614  df-ss 3621  df-nul 3949  df-if 4120  df-sn 4211  df-pr 4213  df-op 4217  df-br 4686  df-opab 4746  df-po 5064  df-so 5065  df-fr 5102  df-se 5103  df-we 5104  df-xp 5149  df-cnv 5151  df-dm 5153  df-rn 5154  df-res 5155  df-ima 5156  df-pred 5718

This theorem is referenced by:  omsinds  7126  uzsinds  12826