Theorem ralxfrALT 4445

Description: Transfer universal quantification from a variable x to another variable y contained in expression A. This proof does not use ralxfrd 4440. (Contributed by NM, 10-Jun-2005.) (Revised by Mario Carneiro, 15-Aug-2014.) (Proof modification is discouraged.) (New usage is discouraged.)

Hypotheses

Ref	Expression
ralxfr.1	|- ( y e. C -> A e. B )
ralxfr.2	|- ( x e. B -> E. y e. C x = A )
ralxfr.3	|- ( x = A -> ( ph <-> ps ) )

Assertion

Ref	Expression
ralxfrALT	|- ( A. x e. B ph <-> A. y e. C ps )

Distinct variable groups:   ps, x   ph, y   x, A   x, y, B   x, C

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

Proof of Theorem ralxfrALT

Step	Hyp	Ref	Expression
1		ralxfr.1	. . . . 5 |- ( y e. C -> A e. B )
2		ralxfr.3	. . . . . 6 |- ( x = A -> ( ph <-> ps ) )
3	2	rspcv 2826	. . . . 5 |- ( A e. B -> ( A. x e. B ph -> ps ) )
4	1, 3	syl 14	. . . 4 |- ( y e. C -> ( A. x e. B ph -> ps ) )
5	4	com12 30	. . 3 |- ( A. x e. B ph -> ( y e. C -> ps ) )
6	5	ralrimiv 2538	. 2 |- ( A. x e. B ph -> A. y e. C ps )
7		ralxfr.2	. . . 4 |- ( x e. B -> E. y e. C x = A )
8		nfra1 2497	. . . . 5 |- F/ y A. y e. C ps
9		nfv 1516	. . . . 5 |- F/ y ph
10		rsp 2513	. . . . . 6 |- ( A. y e. C ps -> ( y e. C -> ps ) )
11	2	biimprcd 159	. . . . . 6 |- ( ps -> ( x = A -> ph ) )
12	10, 11	syl6 33	. . . . 5 |- ( A. y e. C ps -> ( y e. C -> ( x = A -> ph ) ) )
13	8, 9, 12	rexlimd 2580	. . . 4 |- ( A. y e. C ps -> ( E. y e. C x = A -> ph ) )
14	7, 13	syl5 32	. . 3 |- ( A. y e. C ps -> ( x e. B -> ph ) )
15	14	ralrimiv 2538	. 2 |- ( A. y e. C ps -> A. x e. B ph )
16	6, 15	impbii 125	1 |- ( A. x e. B ph <-> A. y e. C ps )

Syntax hints:   -> wi 4   <-> wb 104   = wceq 1343   e. wcel 2136   A.wral 2444   E.wrex 2445

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 105  ax-ia2 106  ax-ia3 107  ax-io 699  ax-5 1435  ax-7 1436  ax-gen 1437  ax-ie1 1481  ax-ie2 1482  ax-8 1492  ax-10 1493  ax-11 1494  ax-i12 1495  ax-bndl 1497  ax-4 1498  ax-17 1514  ax-i9 1518  ax-ial 1522  ax-i5r 1523  ax-ext 2147

This theorem depends on definitions:  df-bi 116  df-tru 1346  df-nf 1449  df-sb 1751  df-clab 2152  df-cleq 2158  df-clel 2161  df-nfc 2297  df-ral 2449  df-rex 2450  df-v 2728

This theorem is referenced by: (None)