MACM 101 Lecture 6: Lecture 6 Part 3_ Logic Inference

• School: Simon Fraser University
• Department: Math & Comp Sci
• Course: MACM 101
• Professor: Andrei Bulatov

Document Summary

Step 2. (p q) r. Step 3. (p r) ( q r) The corresponding tautology ((p q) ( p r)) (q r) Jasmine is skiing or it is not snowing. It is snowing or bart is playing hockey. p - it is snowing q - jasmine is skiing r - bart is playing hockey . Therefore, jasmine is skiing or bart is playing hockey" . Convert the negation of the conclusion into cnf. Consider the collection consisting of all the clauses that occur in the obtained cnfs. Use the rule of resolution to obtain the empty clause ( ). If it is possible, then the argument is valid. The only way to produce the empty clause is to apply the resolution rule to a pair of clauses of the form p and p. In other words, for any choice of truth values for the primitive statements, if premises are true, the conclusion cannot be false.