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

Theorem expi 567
Description: An exportation inference. (Contributed by NM, 5-Aug-1993.) (Proof shortened by O'Cat, 28-Nov-2008.)
Hypothesis
Ref Expression
expi.1  |-  ( -.  ( ph  ->  -.  ps )  ->  ch )
Assertion
Ref Expression
expi  |-  ( ph  ->  ( ps  ->  ch ) )

Proof of Theorem expi
StepHypRef Expression
1 pm3.2im 566 . 2  |-  ( ph  ->  ( ps  ->  -.  ( ph  ->  -.  ps )
) )
2 expi.1 . 2  |-  ( -.  ( ph  ->  -.  ps )  ->  ch )
31, 2syl6 29 1  |-  ( ph  ->  ( ps  ->  ch ) )
Colors of variables: wff set class
Syntax hints:   -. wn 3    -> wi 4
This theorem was proved from axioms:  ax-1 5  ax-2 6  ax-mp 7  ax-in1 544  ax-in2 545
This theorem is referenced by:  bj-nn0suc0  10075
  Copyright terms: Public domain W3C validator