Although in this paper we take modus ponens as the main rule of inference , in general one can consider deductive closures with respect to weaker , nonstandard logics , ( cfXXX Levesque 1984 ; Frisch 1987 ; Patel-Schneider 1985 ) .
a logic of implicit and explicit beliefsquot
H J Levesque
0 is a ground instance of a formula 0 , if 0 contains no variables , and 0 = 00 , for some substitution O. Thus , we do not require Th ( T ) to be closed under substitution instances of tautologies . Although in this paper we take modus ponens as the main rule of inference , in general one can consider deductive closures with respect to weaker , nonstandard logics , ( cfXXX Levesque 1984 ; Frisch 1987 ; Patel-Schneider 1985 ) . But we wo n't pursue this topic further here .
Although in this paper we take modus ponens as the main rule of inference , in general one can consider deductive closures with respect to weaker , nonstandard logics , ( cfXXX @@CITATION ; Frisch 1987 ; Patel-Schneider 1985 ) .