On specificity in default logic
Jussi Rintanen · 1995
The applicability of lexicographic comparison in nonmonotonic reasoning with specificity is investigated. A priority mechanism based on lexicographic comparison is defined for Reiter's default logic. The following principle earlier used by Geffner and Pearl in conditional entailment is used as the basis for specificity-based priorities for normal default theories: for each rule there is a context where it may not be defeated by any other rule. A method for computing priorities according to the principle is given. Connection to earlier work is discussed.