Theorem tfis2 4727

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 1581	. 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 4726	1 |- ( x e. On -> ph )

Syntax hints:   -> wi 4   <-> wb 105   e. wcel 2209   A.wral 2528   Oncon0 4503

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 721  ax-5 1500  ax-7 1501  ax-gen 1502  ax-ie1 1546  ax-ie2 1547  ax-8 1557  ax-10 1558  ax-11 1559  ax-i12 1560  ax-bndl 1562  ax-4 1563  ax-17 1579  ax-i9 1583  ax-ial 1587  ax-i5r 1588  ax-ext 2220  ax-setind 4679

This theorem depends on definitions:  df-bi 117  df-3an 1011  df-tru 1405  df-nf 1514  df-sb 1816  df-clab 2225  df-cleq 2231  df-clel 2234  df-nfc 2381  df-ral 2533  df-rex 2534  df-rab 2537  df-v 2823  df-in 3226  df-ss 3233  df-uni 3931  df-tr 4225  df-iord 4506  df-on 4508

This theorem is referenced by:  tfis3  4728  tfrlem1  6569  ordiso2  7365  exmidontriimlem4  7570  exmidontriim  7571