ILE Home Intuitionistic Logic Explorer < Previous   Next >
Nearby theorems
Mirrors  >  Home  >  ILE Home  >  Th. List  >  19.32r Unicode version

Theorem 19.32r 1570
Description: One direction of Theorem 19.32 of [Margaris] p. 90. The converse holds if  ph is decidable, as seen at 19.32dc 1569. (Contributed by Jim Kingdon, 28-Jul-2018.)
Hypothesis
Ref Expression
19.32r.1  |-  F/ x ph
Assertion
Ref Expression
19.32r  |-  ( (
ph  \/  A. x ps )  ->  A. x
( ph  \/  ps ) )

Proof of Theorem 19.32r
StepHypRef Expression
1 19.32r.1 . . 3  |-  F/ x ph
2 orc 633 . . 3  |-  ( ph  ->  ( ph  \/  ps ) )
31, 2alrimi 1415 . 2  |-  ( ph  ->  A. x ( ph  \/  ps ) )
4 olc 632 . . 3  |-  ( ps 
->  ( ph  \/  ps ) )
54alimi 1344 . 2  |-  ( A. x ps  ->  A. x
( ph  \/  ps ) )
63, 5jaoi 636 1  |-  ( (
ph  \/  A. x ps )  ->  A. x
( ph  \/  ps ) )
Colors of variables: wff set class
Syntax hints:    -> wi 4    \/ wo 629   A.wal 1241   F/wnf 1349
This theorem was proved from axioms:  ax-1 5  ax-2 6  ax-mp 7  ax-ia1 99  ax-ia2 100  ax-ia3 101  ax-io 630  ax-5 1336  ax-gen 1338  ax-4 1400
This theorem depends on definitions:  df-bi 110  df-nf 1350
This theorem is referenced by:  19.31r  1571
  Copyright terms: Public domain W3C validator