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Theorem vtocl2 1818
Description: Implicit substitution of classes for set variables.
Hypotheses
Ref Expression
vtocl2.1 |- A e. V
vtocl2.2 |- B e. V
vtocl2.3 |- ((x = A /\ y = B) -> (ph <-> ps))
vtocl2.4 |- ph
Assertion
Ref Expression
vtocl2 |- ps
Distinct variable groups:   x,y,A   x,B,y   ps,x,y

Proof of Theorem vtocl2
StepHypRef Expression
1 vtocl2.1 . . . . 5 |- A e. V
21isseti 1790 . . . 4 |- E.x x = A
3 vtocl2.2 . . . . 5 |- B e. V
43isseti 1790 . . . 4 |- E.y y = B
5 eeanv 1305 . . . . 5 |- (E.xE.y(x = A /\ y = B) <-> (E.x x = A /\ E.y y = B))
6 vtocl2.3 . . . . . . 7 |- ((x = A /\ y = B) -> (ph <-> ps))
76biimpd 153 . . . . . 6 |- ((x = A /\ y = B) -> (ph -> ps))
8719.22i2 1017 . . . . 5 |- (E.xE.y(x = A /\ y = B) -> E.xE.y(ph -> ps))
95, 8sylbir 201 . . . 4 |- ((E.x x = A /\ E.y y = B) -> E.xE.y(ph -> ps))
102, 4, 9mp2an 694 . . 3 |- E.xE.y(ph -> ps)
11 19.36v 1282 . . . . 5 |- (E.y(ph -> ps) <-> (A.yph -> ps))
1211exbii 1027 . . . 4 |- (E.xE.y(ph -> ps) <-> E.x(A.yph -> ps))
13 19.36v 1282 . . . 4 |- (E.x(A.yph -> ps) <-> (A.xA.yph -> ps))
1412, 13bitr 173 . . 3 |- (E.xE.y(ph -> ps) <-> (A.xA.yph -> ps))
1510, 14mpbi 189 . 2 |- (A.xA.yph -> ps)
16 vtocl2.4 . . 3 |- ph
1716ax-gen 955 . 2 |- A.yph
1815, 17mpg 962 1 |- ps
Colors of variables: wff set class
Syntax hints:   -> wi 3   <-> wb 146   /\ wa 223  A.wal 950  E.wex 956   = wceq 1099   e. wcel 1105  Vcvv 1786
This theorem is referenced by:  caoprcom 3993  caoprord 3996  ersym 4210
This theorem was proved from axioms:  ax-1 4  ax-2 5  ax-3 6  ax-mp 7  ax-4 951  ax-5 952  ax-6 953  ax-7 954  ax-gen 955  ax-9 1102  ax-12 1104  ax-17 1190  ax-ext 1436
This theorem depends on definitions:  df-bi 147  df-or 224  df-an 225  df-ex 957  df-sb 1155  df-clab 1441  df-cleq 1446  df-clel 1449  df-v 1787
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