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Knowledge Representation and Reasoning

Knowledge Representation and Reasoning

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Resolution algorithm<br />

Proof by contradiction, i.e., show KB ∧ ¬α unsatisfiable<br />

clauses ←<br />

new ← { }<br />

£ PL-RESOLUTION<br />

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KB<br />

α<br />

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true<br />

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false<br />

KB ∧ ¬α<br />

C j<br />

£ clauses<br />

resolvents ← PL-RESOLVE<br />

resolvents<br />

new ←new ∪resolvents<br />

new ⊆ clauses<br />

clauses ←clauses ∪new<br />

£ <br />

©¨<br />

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C j<br />

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false<br />

true<br />

<strong>Knowledge</strong> <strong>Representation</strong> <strong>and</strong> <strong>Reasoning</strong> – 31

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