Users' Mathboxes Mathbox for Andrew Salmon < Previous   Next >
Nearby theorems
Mirrors  >  Home  >  MPE Home  >  Th. List  >   Mathboxes  >  pm10.252 Unicode version

Theorem pm10.252 26722
Description: Theorem *10.252 in [WhiteheadRussell] p. 149. (Contributed by Andrew Salmon, 17-Jun-2011.)
Assertion
Ref Expression
pm10.252  |-  ( -. 
E. x ph  <->  A. x  -.  ph )

Proof of Theorem pm10.252
StepHypRef Expression
1 df-ex 1538 . . 3  |-  ( E. x ph  <->  -.  A. x  -.  ph )
21bicomi 195 . 2  |-  ( -. 
A. x  -.  ph  <->  E. x ph )
32con1bii 323 1  |-  ( -. 
E. x ph  <->  A. x  -.  ph )
Colors of variables: wff set class
Syntax hints:   -. wn 5    <-> wb 178   A.wal 1532   E.wex 1537
This theorem was proved from axioms:  ax-1 7  ax-2 8  ax-3 9  ax-mp 10
This theorem depends on definitions:  df-bi 179  df-ex 1538
  Copyright terms: Public domain W3C validator