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Theorem sbabel 2248
Description: Theorem to move a substitution in and out of a class abstraction. (Contributed by NM, 27-Sep-2003.) (Revised by Mario Carneiro, 7-Oct-2016.)
Hypothesis
Ref Expression
sbabel.1  |-  F/_ x A
Assertion
Ref Expression
sbabel  |-  ( [ y  /  x ] { z  |  ph }  e.  A  <->  { z  |  [ y  /  x ] ph }  e.  A
)
Distinct variable groups:    x, z    y,
z
Allowed substitution hints:    ph( x, y, z)    A( x, y, z)

Proof of Theorem sbabel
Dummy variable  v is distinct from all other variables.
StepHypRef Expression
1 sbex 1923 . . 3  |-  ( [ y  /  x ] E. v ( v  =  { z  |  ph }  /\  v  e.  A
)  <->  E. v [ y  /  x ] ( v  =  { z  |  ph }  /\  v  e.  A )
)
2 sban 1872 . . . . 5  |-  ( [ y  /  x ]
( v  =  {
z  |  ph }  /\  v  e.  A
)  <->  ( [ y  /  x ] v  =  { z  | 
ph }  /\  [
y  /  x ]
v  e.  A ) )
3 nfv 1462 . . . . . . . . . 10  |-  F/ x  z  e.  v
43sbf 1702 . . . . . . . . 9  |-  ( [ y  /  x ]
z  e.  v  <->  z  e.  v )
54sbrbis 1878 . . . . . . . 8  |-  ( [ y  /  x ]
( z  e.  v  <->  ph )  <->  ( z  e.  v  <->  [ y  /  x ] ph ) )
65sbalv 1924 . . . . . . 7  |-  ( [ y  /  x ] A. z ( z  e.  v  <->  ph )  <->  A. z
( z  e.  v  <->  [ y  /  x ] ph ) )
7 abeq2 2191 . . . . . . . 8  |-  ( v  =  { z  | 
ph }  <->  A. z
( z  e.  v  <->  ph ) )
87sbbii 1690 . . . . . . 7  |-  ( [ y  /  x ]
v  =  { z  |  ph }  <->  [ y  /  x ] A. z
( z  e.  v  <->  ph ) )
9 abeq2 2191 . . . . . . 7  |-  ( v  =  { z  |  [ y  /  x ] ph }  <->  A. z
( z  e.  v  <->  [ y  /  x ] ph ) )
106, 8, 93bitr4i 210 . . . . . 6  |-  ( [ y  /  x ]
v  =  { z  |  ph }  <->  v  =  { z  |  [
y  /  x ] ph } )
11 sbabel.1 . . . . . . . 8  |-  F/_ x A
1211nfcri 2217 . . . . . . 7  |-  F/ x  v  e.  A
1312sbf 1702 . . . . . 6  |-  ( [ y  /  x ]
v  e.  A  <->  v  e.  A )
1410, 13anbi12i 448 . . . . 5  |-  ( ( [ y  /  x ] v  =  {
z  |  ph }  /\  [ y  /  x ] v  e.  A
)  <->  ( v  =  { z  |  [
y  /  x ] ph }  /\  v  e.  A ) )
152, 14bitri 182 . . . 4  |-  ( [ y  /  x ]
( v  =  {
z  |  ph }  /\  v  e.  A
)  <->  ( v  =  { z  |  [
y  /  x ] ph }  /\  v  e.  A ) )
1615exbii 1537 . . 3  |-  ( E. v [ y  /  x ] ( v  =  { z  |  ph }  /\  v  e.  A
)  <->  E. v ( v  =  { z  |  [ y  /  x ] ph }  /\  v  e.  A ) )
171, 16bitri 182 . 2  |-  ( [ y  /  x ] E. v ( v  =  { z  |  ph }  /\  v  e.  A
)  <->  E. v ( v  =  { z  |  [ y  /  x ] ph }  /\  v  e.  A ) )
18 df-clel 2079 . . 3  |-  ( { z  |  ph }  e.  A  <->  E. v ( v  =  { z  | 
ph }  /\  v  e.  A ) )
1918sbbii 1690 . 2  |-  ( [ y  /  x ] { z  |  ph }  e.  A  <->  [ y  /  x ] E. v
( v  =  {
z  |  ph }  /\  v  e.  A
) )
20 df-clel 2079 . 2  |-  ( { z  |  [ y  /  x ] ph }  e.  A  <->  E. v
( v  =  {
z  |  [ y  /  x ] ph }  /\  v  e.  A
) )
2117, 19, 203bitr4i 210 1  |-  ( [ y  /  x ] { z  |  ph }  e.  A  <->  { z  |  [ y  /  x ] ph }  e.  A
)
Colors of variables: wff set class
Syntax hints:    /\ wa 102    <-> wb 103   A.wal 1283    = wceq 1285   E.wex 1422    e. wcel 1434   [wsb 1687   {cab 2069   F/_wnfc 2210
This theorem was proved from axioms:  ax-1 5  ax-2 6  ax-mp 7  ax-ia1 104  ax-ia2 105  ax-ia3 106  ax-io 663  ax-5 1377  ax-7 1378  ax-gen 1379  ax-ie1 1423  ax-ie2 1424  ax-8 1436  ax-10 1437  ax-11 1438  ax-i12 1439  ax-bndl 1440  ax-4 1441  ax-17 1460  ax-i9 1464  ax-ial 1468  ax-i5r 1469  ax-ext 2065
This theorem depends on definitions:  df-bi 115  df-nf 1391  df-sb 1688  df-clab 2070  df-cleq 2076  df-clel 2079  df-nfc 2212
This theorem is referenced by: (None)
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