Circumscription and Definability
نویسندگان
چکیده
Thanks to two stronger versions of predicate circumscription (one of the best known non-monotonic reasoning methods), we give a definitive answer to two old open problems. The first one is the problem of expressing domain circumscription in terms of predicate circumscription. The second one is the problem of definability of the circumscribed predicates, asked by Doyle in 1985, and never answered since. These two results, and the way used to obtain them, could help an "automatic circumscriptor".
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