Logical Reasoning

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Logical Reasoning

• First Order Predicate Logic as a Language
• Resolution
• For Propositional Calculus
• For First Order Predicate Calculus
• Unification
• Resolution and PROLOG very short!
• Textbooks Perspective knowledge based systems
  giving a somewhat comprehensive introduction to
  logic cover 7,9,10
• 6368 Perspective Using FOPL to make statements
  about the world use computers to prove theorems
  and for question-answering.

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Using Resolution for Propositional Calculus

• Makes a proof by contradiction
• Works with clauses --- knowledge is represented
  as a conjunct of disjuncts (conjunctive normal
  form)
• Does not use modus ponens uses the inference
  rule of resolution (m,n?0)
• A1 vv An v C B1vv Bm v C
• _____________________________
• A1vv An v B1vv Bm
• Steps of a resolution proof
• Convert assumption into clauses
• Convert negated conclusion into clauses
• Determine if the empty clause can