Theorem ralab2 2756

Description: Universal quantification over a class abstraction. (Contributed by Mario Carneiro, 3-Sep-2015.)

Hypothesis

Ref	Expression
ralab2.1	|- ( x = y -> ( ps <-> ch ) )

Assertion

Ref	Expression
ralab2	|- ( A. x e. { y | ph } ps <-> A. y ( ph -> ch ) )

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

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

Proof of Theorem ralab2

Step	Hyp	Ref	Expression
1		df-ral 2353	. 2 |- ( A. x e. { y | ph } ps <-> A. x ( x e. { y | ph } -> ps ) )
2		nfsab1 2071	. . . 4 |- F/ y x e. { y | ph }
3		nfv 1461	. . . 4 |- F/ y ps
4	2, 3	nfim 1504	. . 3 |- F/ y ( x e. { y | ph } -> ps )
5		nfv 1461	. . 3 |- F/ x ( ph -> ch )
6		eleq1 2141	. . . . 5 |- ( x = y -> ( x e. { y | ph } <-> y e. { y | ph } ) )
7		abid 2069	. . . . 5 |- ( y e. { y | ph } <-> ph )
8	6, 7	syl6bb 194	. . . 4 |- ( x = y -> ( x e. { y | ph } <-> ph ) )
9		ralab2.1	. . . 4 |- ( x = y -> ( ps <-> ch ) )
10	8, 9	imbi12d 232	. . 3 |- ( x = y -> ( ( x e. { y | ph } -> ps ) <-> ( ph -> ch ) ) )
11	4, 5, 10	cbval 1677	. 2 |- ( A. x ( x e. { y | ph } -> ps ) <-> A. y ( ph -> ch ) )
12	1, 11	bitri 182	1 |- ( A. x e. { y | ph } ps <-> A. y ( ph -> ch ) )

Syntax hints:   -> wi 4   <-> wb 103   A.wal 1282   e. wcel 1433   {cab 2067   A.wral 2348

This theorem was proved from axioms:  ax-1 5  ax-2 6  ax-mp 7  ax-ia1 104  ax-ia2 105  ax-ia3 106  ax-5 1376  ax-7 1377  ax-gen 1378  ax-ie1 1422  ax-ie2 1423  ax-8 1435  ax-11 1437  ax-4 1440  ax-17 1459  ax-i9 1463  ax-ial 1467  ax-i5r 1468  ax-ext 2063

This theorem depends on definitions:  df-bi 115  df-nf 1390  df-sb 1686  df-clab 2068  df-cleq 2074  df-clel 2077  df-ral 2353

This theorem is referenced by:  ralrab2  2757  ssintab  3653