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Theorem axrep4 2702
Description: A more traditional version of the Axiom of Replacement.
Hypothesis
Ref Expression
axrep4.1 |- (ph -> A.zph)
Assertion
Ref Expression
axrep4 |- (A.xE.zA.y(ph -> y = z) -> E.zA.y(y e. z <-> E.x(x e. w /\ ph)))
Distinct variable group:   x,y,z,w

Proof of Theorem axrep4
StepHypRef Expression
1 axrep3 2701 . . 3 |- E.x(E.zA.y(ph -> y = z) -> A.y(y e. x <-> E.x(x e. w /\ A.zph)))
2119.35i 1078 . 2 |- (A.xE.zA.y(ph -> y = z) -> E.xA.y(y e. x <-> E.x(x e. w /\ A.zph)))
3 ax-17 973 . . . . 5 |- (y e. x -> A.z y e. x)
4 ax-17 973 . . . . . . 7 |- (x e. w -> A.z x e. w)
5 hba1 1005 . . . . . . 7 |- (A.zph -> A.zA.zph)
64, 5hban 1011 . . . . . 6 |- ((x e. w /\ A.zph) -> A.z(x e. w /\ A.zph))
76hbex 1008 . . . . 5 |- (E.x(x e. w /\ A.zph) -> A.zE.x(x e. w /\ A.zph))
83, 7hbbi 1012 . . . 4 |- ((y e. x <-> E.x(x e. w /\ A.zph)) -> A.z(y e. x <-> E.x(x e. w /\ A.zph)))
98hbal 1007 . . 3 |- (A.y(y e. x <-> E.x(x e. w /\ A.zph)) -> A.zA.y(y e. x <-> E.x(x e. w /\ A.zph)))
10 ax-17 973 . . . . 5 |- (y e. z -> A.x y e. z)
11 hbe1 1018 . . . . 5 |- (E.x(x e. w /\ ph) -> A.xE.x(x e. w /\ ph))
1210, 11hbbi 1012 . . . 4 |- ((y e. z <-> E.x(x e. w /\ ph)) -> A.x(y e. z <-> E.x(x e. w /\ ph)))
1312hbal 1007 . . 3 |- (A.y(y e. z <-> E.x(x e. w /\ ph)) -> A.xA.y(y e. z <-> E.x(x e. w /\ ph)))
14 ax-17 973 . . . 4 |- (x = z -> A.y x = z)
15 elequ2 1139 . . . . 5 |- (x = z -> (y e. x <-> y e. z))
16 axrep4.1 . . . . . . . . 9 |- (ph -> A.zph)
171619.3 1033 . . . . . . . 8 |- (A.zph <-> ph)
1817anbi2i 482 . . . . . . 7 |- ((x e. w /\ A.zph) <-> (x e. w /\ ph))
1918exbii 1053 . . . . . 6 |- (E.x(x e. w /\ A.zph) <-> E.x(x e. w /\ ph))
2019a1i 8 . . . . 5 |- (x = z -> (E.x(x e. w /\ A.zph) <-> E.x(x e. w /\ ph)))
2115, 20bibi12d 631 . . . 4 |- (x = z -> ((y e. x <-> E.x(x e. w /\ A.zph)) <-> (y e. z <-> E.x(x e. w /\ ph))))
2214, 21albid 1106 . . 3 |- (x = z -> (A.y(y e. x <-> E.x(x e. w /\ A.zph)) <-> A.y(y e. z <-> E.x(x e. w /\ ph))))
239, 13, 22cbvex 1168 . 2 |- (E.xA.y(y e. x <-> E.x(x e. w /\ A.zph)) <-> E.zA.y(y e. z <-> E.x(x e. w /\ ph)))
242, 23sylib 198 1 |- (A.xE.zA.y(ph -> y = z) -> E.zA.y(y e. z <-> E.x(x e. w /\ ph)))
Colors of variables: wff set class
Syntax hints:   -> wi 3   <-> wb 146   /\ wa 223  A.wal 956   = wceq 958   e. wcel 960  E.wex 982
This theorem is referenced by:  axrep5 2703  funimaexg 3581
This theorem was proved from axioms:  ax-1 4  ax-2 5  ax-3 6  ax-mp 7  ax-7 964  ax-gen 965  ax-8 966  ax-12 970  ax-14 972  ax-17 973  ax-4 975  ax-5o 977  ax-6o 980  ax-9o 1125  ax-rep 2698
This theorem depends on definitions:  df-bi 147  df-an 225  df-ex 983
Copyright terms: Public domain