An abductive logic framework, consisting of a set of abducible predicates, a set of rules and a set of FOL constraints can be embedded in ID-logic as the theory consisting of the FOL constraints and one deﬁnition deﬁning all non-abducible predicates.
SLDNFA-system
Note that has position(i,j) has no deﬁnition therefore it should be declared an open predicate by the declaration abducible(has_position(_,_)).
SLDNFA-system
Agent reasoning is speciﬁed by abductive logic programs con sisting of a set of clauses Head :- Body, where Head is an atom and Body is a conjunction of literals (atoms and negation of atoms), plus a set of abducible predicates and a set of integrity constraints.
Logic-Based Specification Languages for Intelligent Software Agents
It can be thought of as a form of hypothetical reasoning: to ask what can be abduced from an observation α is to ask for an explanation, which in conjunction with the given background knowledge accounts for α.
Complexity of Non-Monotonic Logics
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