ILE Home Intuitionistic Logic Explorer < Previous   Next >
Nearby theorems
Mirrors  >  Home  >  ILE Home  >  Th. List  >  sbcbi1 Unicode version

Theorem sbcbi1 3024
Description: Distribution of class substitution over biconditional. One direction of sbcbig 3021 that holds for proper classes. (Contributed by NM, 17-Aug-2018.)
Assertion
Ref Expression
sbcbi1  |-  ( [. A  /  x ]. ( ph 
<->  ps )  ->  ( [. A  /  x ]. ph  <->  [. A  /  x ]. ps ) )

Proof of Theorem sbcbi1
StepHypRef Expression
1 sbcex 2983 . 2  |-  ( [. A  /  x ]. ( ph 
<->  ps )  ->  A  e.  _V )
2 sbcbig 3021 . . 3  |-  ( A  e.  _V  ->  ( [. A  /  x ]. ( ph  <->  ps )  <->  (
[. A  /  x ]. ph  <->  [. A  /  x ]. ps ) ) )
32biimpd 144 . 2  |-  ( A  e.  _V  ->  ( [. A  /  x ]. ( ph  <->  ps )  ->  ( [. A  /  x ]. ph  <->  [. A  /  x ]. ps ) ) )
41, 3mpcom 36 1  |-  ( [. A  /  x ]. ( ph 
<->  ps )  ->  ( [. A  /  x ]. ph  <->  [. A  /  x ]. ps ) )
Colors of variables: wff set class
Syntax hints:    -> wi 4    <-> wb 105    e. wcel 2158   _Vcvv 2749   [.wsbc 2974
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 1457  ax-7 1458  ax-gen 1459  ax-ie1 1503  ax-ie2 1504  ax-8 1514  ax-10 1515  ax-11 1516  ax-i12 1517  ax-bndl 1519  ax-4 1520  ax-17 1536  ax-i9 1540  ax-ial 1544  ax-i5r 1545  ax-ext 2169
This theorem depends on definitions:  df-bi 117  df-tru 1366  df-nf 1471  df-sb 1773  df-clab 2174  df-cleq 2180  df-clel 2183  df-nfc 2318  df-v 2751  df-sbc 2975
This theorem is referenced by: (None)
  Copyright terms: Public domain W3C validator