Theorem reupick3 3222

Description: Restricted uniqueness "picks" a member of a subclass. (Contributed by Mario Carneiro, 19-Nov-2016.)

Assertion

Ref	Expression
reupick3	|- ( ( E! x e. A ph /\ E. x e. A ( ph /\ ps ) /\ x e. A ) -> ( ph -> ps ) )

Distinct variable group:   x, A

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

Proof of Theorem reupick3

Step	Hyp	Ref	Expression
1		df-reu 2313	. . . 4 |- ( E! x e. A ph <-> E! x ( x e. A /\ ph ) )
2		df-rex 2312	. . . . 5 |- ( E. x e. A ( ph /\ ps ) <-> E. x ( x e. A /\ ( ph /\ ps ) ) )
3		anass 381	. . . . . 6 |- ( ( ( x e. A /\ ph ) /\ ps ) <-> ( x e. A /\ ( ph /\ ps ) ) )
4	3	exbii 1496	. . . . 5 |- ( E. x ( ( x e. A /\ ph ) /\ ps ) <-> E. x ( x e. A /\ ( ph /\ ps ) ) )
5	2, 4	bitr4i 176	. . . 4 |- ( E. x e. A ( ph /\ ps ) <-> E. x ( ( x e. A /\ ph ) /\ ps ) )
6		eupick 1979	. . . 4 |- ( ( E! x ( x e. A /\ ph ) /\ E. x ( ( x e. A /\ ph ) /\ ps ) ) -> ( ( x e. A /\ ph ) -> ps ) )
7	1, 5, 6	syl2anb 275	. . 3 |- ( ( E! x e. A ph /\ E. x e. A ( ph /\ ps ) ) -> ( ( x e. A /\ ph ) -> ps ) )
8	7	expd 245	. 2 |- ( ( E! x e. A ph /\ E. x e. A ( ph /\ ps ) ) -> ( x e. A -> ( ph -> ps ) ) )
9	8	3impia 1101	1 |- ( ( E! x e. A ph /\ E. x e. A ( ph /\ ps ) /\ x e. A ) -> ( ph -> ps ) )

Syntax hints:   -> wi 4   /\ wa 97   /\ w3a 885   E.wex 1381   e. wcel 1393   E!weu 1900   E.wrex 2307   E!wreu 2308

This theorem was proved from axioms:  ax-1 5  ax-2 6  ax-mp 7  ax-ia1 99  ax-ia2 100  ax-ia3 101  ax-io 630  ax-5 1336  ax-7 1337  ax-gen 1338  ax-ie1 1382  ax-ie2 1383  ax-8 1395  ax-10 1396  ax-11 1397  ax-i12 1398  ax-bndl 1399  ax-4 1400  ax-17 1419  ax-i9 1423  ax-ial 1427  ax-i5r 1428

This theorem depends on definitions:  df-bi 110  df-3an 887  df-nf 1350  df-sb 1646  df-eu 1903  df-mo 1904  df-rex 2312  df-reu 2313

This theorem is referenced by:  reupick2  3223