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Theorem sbralie 2760
Description: Implicit to explicit substitution that swaps variables in a quantified expression. (Contributed by NM, 5-Sep-2004.)
Hypothesis
Ref Expression
sbralie.1  |-  ( x  =  y  ->  ( ph 
<->  ps ) )
Assertion
Ref Expression
sbralie  |-  ( A. x  e.  y  ph  <->  [ y  /  x ] A. y  e.  x  ps )
Distinct variable groups:    x, y    ps, x    ph, y
Allowed substitution hints:    ph( x)    ps( y)

Proof of Theorem sbralie
Dummy variable  z is distinct from all other variables.
StepHypRef Expression
1 cbvralsv 2758 . . 3  |-  ( A. y  e.  x  ps  <->  A. z  e.  x  [
z  /  y ] ps )
21sbbii 1789 . 2  |-  ( [ y  /  x ] A. y  e.  x  ps 
<->  [ y  /  x ] A. z  e.  x  [ z  /  y ] ps )
3 nfv 1552 . . 3  |-  F/ x A. z  e.  y  [ z  /  y ] ps
4 raleq 2705 . . 3  |-  ( x  =  y  ->  ( A. z  e.  x  [ z  /  y ] ps  <->  A. z  e.  y  [ z  /  y ] ps ) )
53, 4sbie 1815 . 2  |-  ( [ y  /  x ] A. z  e.  x  [ z  /  y ] ps  <->  A. z  e.  y  [ z  /  y ] ps )
6 cbvralsv 2758 . . 3  |-  ( A. z  e.  y  [
z  /  y ] ps  <->  A. x  e.  y  [ x  /  z ] [ z  /  y ] ps )
7 nfv 1552 . . . . . 6  |-  F/ z ps
87sbco2 1994 . . . . 5  |-  ( [ x  /  z ] [ z  /  y ] ps  <->  [ x  /  y ] ps )
9 nfv 1552 . . . . . 6  |-  F/ y
ph
10 sbralie.1 . . . . . . . 8  |-  ( x  =  y  ->  ( ph 
<->  ps ) )
1110bicomd 141 . . . . . . 7  |-  ( x  =  y  ->  ( ps 
<-> 
ph ) )
1211equcoms 1732 . . . . . 6  |-  ( y  =  x  ->  ( ps 
<-> 
ph ) )
139, 12sbie 1815 . . . . 5  |-  ( [ x  /  y ] ps  <->  ph )
148, 13bitri 184 . . . 4  |-  ( [ x  /  z ] [ z  /  y ] ps  <->  ph )
1514ralbii 2514 . . 3  |-  ( A. x  e.  y  [
x  /  z ] [ z  /  y ] ps  <->  A. x  e.  y 
ph )
166, 15bitri 184 . 2  |-  ( A. z  e.  y  [
z  /  y ] ps  <->  A. x  e.  y 
ph )
172, 5, 163bitrri 207 1  |-  ( A. x  e.  y  ph  <->  [ y  /  x ] A. y  e.  x  ps )
Colors of variables: wff set class
Syntax hints:    -> wi 4    <-> wb 105   [wsb 1786   A.wral 2486
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 711  ax-5 1471  ax-7 1472  ax-gen 1473  ax-ie1 1517  ax-ie2 1518  ax-8 1528  ax-10 1529  ax-11 1530  ax-i12 1531  ax-bndl 1533  ax-4 1534  ax-17 1550  ax-i9 1554  ax-ial 1558  ax-i5r 1559  ax-ext 2189
This theorem depends on definitions:  df-bi 117  df-tru 1376  df-nf 1485  df-sb 1787  df-cleq 2200  df-clel 2203  df-nfc 2339  df-ral 2491
This theorem is referenced by: (None)
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