clausalformeg

clausalformeg - not (not ls(john) or (all Z not...

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This concerns the step in reduction-to-clausal-form involving reducing the scope of negation. This example shows that if you perform some of these steps before others, you will perform unnecessary steps. However, you will eventually get the right answer, regardless of the order in which you apply them. Example: not (ls(john) -> not (not ls(john) or (all Z not (have(john,Z) & mouse(Z)))). CHOICE HERE not (not ls(john) or (all Z (not have(john,Z) or not mouse(Z)))). ls(john) & have(john,c22) & mouse(c22)). 3 CLAUSES ========= not (ls(john) -> not (not ls(john) or (not (exists Z (have(john,Z) & mouse(Z))))). SAME CHOICE
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Unformatted text preview: not (not ls(john) or (all Z not (have(john,Z) & mouse(Z)))). OTHER CHOICE not (not ls(john) or (all Z not (have(john,Z) & mouse(Z)))). ls(john) & not (all Z not (have(john,Z) & mouse(Z)))). CHOICE HERE ls(john) & not (all Z (not have(john,Z) or not mouse(Z))). CHOICE HERE ls(john) & exists Z not (not have(john,Z) or not mouse(Z))). CHOICE HERE ls(john) & exists Z (have(john,Z) & mouse(Z)). ls(john) & have(john,c22) & mouse(c22). 3 CLAUSES =========== There are others . .. =========== SHORTEST PROCESS: work on outer scopes first not (ls(john) -> (not (exists Z (have(john,Z) & mouse(Z))))). not (not ls(john) or (not (exists Z (have(john,Z) & mouse(Z))))). CHOICE HERE ls(john) & (exists Z (have(john,Z) & mouse(Z))). ls(john) & have(john,c22) & mouse(c22). 3 CLAUSES ============...
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