Logical Entailment
Logical Satisfaction
Interpretation I logically satisfies a sentence S
if and only if TIV(S) is true for all variable assignments V.
E.g., (=> (Block ?b1)
(or (On ?b1 table)
(exists ?b2 (and (Block ?b2) (On ?b1 b2)))))
Models
Interpretation I is a model of a sentence S if and only if I logically satisfies S.
Logical Entailment
Sentence S1 logically entails sentence S2 if and only if every model of S1 is also a model of S2.
E.g., “(and S3 (=> S3 S4))” logically entails S4