Theorem tfis2 4689

Description: Transfinite Induction Schema, using implicit substitution. (Contributed by NM, 18-Aug-1994.)

Hypotheses

Ref	Expression
tfis2.1	|- ( x = y -> ( ph <-> ps ) )
tfis2.2	|- ( x e. On -> ( A. y e. x ps -> ph ) )

Assertion

Ref	Expression
tfis2	|- ( x e. On -> ph )

Distinct variable groups:   ps, x   ph, y   x, y

Allowed substitution hints:   ph( x)   ps( y)

Proof of Theorem tfis2

Step	Hyp	Ref	Expression
1		nfv 1577	. 2 |- F/ x ps
2		tfis2.1	. 2 |- ( x = y -> ( ph <-> ps ) )
3		tfis2.2	. 2 |- ( x e. On -> ( A. y e. x ps -> ph ) )
4	1, 2, 3	tfis2f 4688	1 |- ( x e. On -> ph )

Syntax hints:   -> wi 4   <-> wb 105   e. wcel 2202   A.wral 2511   Oncon0 4466

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-io 717  ax-5 1496  ax-7 1497  ax-gen 1498  ax-ie1 1542  ax-ie2 1543  ax-8 1553  ax-10 1554  ax-11 1555  ax-i12 1556  ax-bndl 1558  ax-4 1559  ax-17 1575  ax-i9 1579  ax-ial 1583  ax-i5r 1584  ax-ext 2213  ax-setind 4641

This theorem depends on definitions:  df-bi 117  df-3an 1007  df-tru 1401  df-nf 1510  df-sb 1811  df-clab 2218  df-cleq 2224  df-clel 2227  df-nfc 2364  df-ral 2516  df-rex 2517  df-rab 2520  df-v 2805  df-in 3207  df-ss 3214  df-uni 3899  df-tr 4193  df-iord 4469  df-on 4471

This theorem is referenced by:  tfis3  4690  tfrlem1  6517  ordiso2  7277  exmidontriimlem4  7482  exmidontriim  7483