Theorem isarep1 5344

Description: Part of a study of the Axiom of Replacement used by the Isabelle prover. The object PrimReplace is apparently the image of the function encoded by ph ( x , y ) i.e. the class ( { <. x , y >. | ph } " A ). If so, we can prove Isabelle's "Axiom of Replacement" conclusion without using the Axiom of Replacement, for which I (N. Megill) currently have no explanation. (Contributed by NM, 26-Oct-2006.) (Proof shortened by Mario Carneiro, 4-Dec-2016.)

Assertion

Ref	Expression
isarep1	|- ( b e. ( { <. x , y >. | ph } " A ) <-> E. x e. A [ b / y ] ph )

Distinct variable groups:   x, A   x, b, y

Allowed substitution hints:   ph( x, y, b)   A( y, b)

Proof of Theorem isarep1

Dummy variable z is distinct from all other variables.

Step	Hyp	Ref	Expression
1		vex 2766	. . 3 |- b e. _V
2	1	elima 5014	. 2 |- ( b e. ( { <. x , y >. | ph } " A ) <-> E. z e. A z { <. x , y >. | ph } b )
3		df-br 4034	. . . 4 |- ( z { <. x , y >. | ph } b <-> <. z , b >. e. { <. x , y >. | ph } )
4		opelopabsb 4294	. . . 4 |- ( <. z , b >. e. { <. x , y >. | ph } <-> [. z / x ]. [. b / y ]. ph )
5		sbsbc 2993	. . . . . 6 |- ( [ b / y ] ph <-> [. b / y ]. ph )
6	5	sbbii 1779	. . . . 5 |- ( [ z / x ] [ b / y ] ph <-> [ z / x ] [. b / y ]. ph )
7		sbsbc 2993	. . . . 5 |- ( [ z / x ] [. b / y ]. ph <-> [. z / x ]. [. b / y ]. ph )
8	6, 7	bitr2i 185	. . . 4 |- ( [. z / x ]. [. b / y ]. ph <-> [ z / x ] [ b / y ] ph )
9	3, 4, 8	3bitri 206	. . 3 |- ( z { <. x , y >. | ph } b <-> [ z / x ] [ b / y ] ph )
10	9	rexbii 2504	. 2 |- ( E. z e. A z { <. x , y >. | ph } b <-> E. z e. A [ z / x ] [ b / y ] ph )
11		nfs1v 1958	. . 3 |- F/ x [ z / x ] [ b / y ] ph
12		nfv 1542	. . 3 |- F/ z [ b / y ] ph
13		sbequ12r 1786	. . 3 |- ( z = x -> ( [ z / x ] [ b / y ] ph <-> [ b / y ] ph ) )
14	11, 12, 13	cbvrex 2726	. 2 |- ( E. z e. A [ z / x ] [ b / y ] ph <-> E. x e. A [ b / y ] ph )
15	2, 10, 14	3bitri 206	1 |- ( b e. ( { <. x , y >. | ph } " A ) <-> E. x e. A [ b / y ] ph )

Syntax hints:   <-> wb 105   [wsb 1776   e. wcel 2167   E.wrex 2476   [.wsbc 2989   <.cop 3625   class class class wbr 4033   {copab 4093   "cima 4666

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 106  ax-ia2 107  ax-ia3 108  ax-io 710  ax-5 1461  ax-7 1462  ax-gen 1463  ax-ie1 1507  ax-ie2 1508  ax-8 1518  ax-10 1519  ax-11 1520  ax-i12 1521  ax-bndl 1523  ax-4 1524  ax-17 1540  ax-i9 1544  ax-ial 1548  ax-i5r 1549  ax-14 2170  ax-ext 2178  ax-sep 4151  ax-pow 4207  ax-pr 4242

This theorem depends on definitions:  df-bi 117  df-3an 982  df-tru 1367  df-nf 1475  df-sb 1777  df-eu 2048  df-mo 2049  df-clab 2183  df-cleq 2189  df-clel 2192  df-nfc 2328  df-ral 2480  df-rex 2481  df-v 2765  df-sbc 2990  df-un 3161  df-in 3163  df-ss 3170  df-pw 3607  df-sn 3628  df-pr 3629  df-op 3631  df-br 4034  df-opab 4095  df-xp 4669  df-cnv 4671  df-dm 4673  df-rn 4674  df-res 4675  df-ima 4676

This theorem is referenced by: (None)