10. The method of claim 9 , wherein said abducing further comprises: creating one or more sub-goals such that said query is true when each of the one or more sub-goals is met; creating a second answer set under which a first one of said sub-goals is true under said policy; determining that said second answer set is subsumed by a fourth answer set; and creating said first answer set based on said fourth answer set.
12. The method of claim 10 , wherein said second answer set comprises a first collection of one or more variables, wherein said fourth answer set comprises a second collection of one or more variables, and wherein said determining that said second answer set is subsumed by said fourth answer set comprises: determining whether a substitution, which defines relationships among variables, exists such that one or more conditions involving said second answer set and said fourth answer set are satisfied when said substitution is applied to said first collection and said second collection.