Inference

• Inference -

  Determining conclusions logically entailed by premises
  

• Patterns of inference represented as inference rules

• Example inference rules -

  Modus Ponens Modus Tollens
  
  (implies S1 S2), S1 (implies S1 S2), (not S2)
  ------------ ---------------
  S2 (not S1)

• An inference rule can be verified using a truth table

  S1 S2 (not S1) (not S2) (implies S1 S2)
  
  _____________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________
  True True False False True
  True False False True False
  False True True False True
  False False True True True

Previous slide

Next slide

Back to first slide

View graphic version