Logic and Proof: Resolution Lecture

VibrantLitotes avatar
VibrantLitotes
·
·
Download

Start Quiz

Study Flashcards

10 Questions

What is the result of deleting P from all clauses in F that contain P?

F [false/P ]

How is F [true/P ] defined?

By deleting all clauses containing P and removing ¬P from all clauses containing ¬P

What is the result of F [false/p3 ] when F = {{p1 , p3 }, {¬p1 , p2 }, {¬p2 , p3 }, {¬p3 }}?

{{p1 }, {¬p1 , p2 }, {¬p2 }}

What is the purpose of Theorem 8 (Completeness)?

To prove that if F is unsatisfiable, then there is a derivation of 2 from F

What is the base case in the proof of Theorem 8 (Completeness)?

When n = 0, i.e., F does not mention any propositional variables

What is the result of F [true/p3 ] when F = {{p1 , p3 }, {¬p1 , p2 }, {¬p2 , p3 }, {¬p3 }}?

{{¬p1 , p2 }, 2}

What is the induction step in the proof of Theorem 8 (Completeness)?

Suppose that F is an unsatisfiable set of clauses that mentions variables p1 , p2 ,..., pn and let F0 := F [false/pn ] and F1 := F [true/pn ]

What is the consequence of F being unsatisfiable in the proof of Theorem 8 (Completeness)?

F0 is also unsatisfiable

What is the purpose of defining F0 and F1 in the proof of Theorem 8 (Completeness)?

To apply the induction hypothesis and derive the empty clause from F

What is the result of the induction step in the proof of Theorem 8 (Completeness)?

A resolution proof C0 , C1 ,..., Cm = 2 that derives the empty clause from F0

This lecture introduces a proof calculus for propositional logic, specifically the resolution method, which has a single rule of inference, making it suitable for automation and theoretical analysis.

Make Your Own Quizzes and Flashcards

Convert your notes into interactive study material.

Get started for free
Use Quizgecko on...
Browser
Browser