Circumscription: Completeness reviewed (Q685339)

The author gives a counterexample to the minimality result of \textit{D. Perlis} and \textit{J. Minker} [Completeness results for circumscription, Artif. Intell. 28, 29-42 (1986; Zbl 0589.03021)] but shows that the result still holds if it is restricted to well-founded theories in the sense that every nonminimal model contains a minimal model and if the notion of circumscription is strengthened. He also investigates the relationship between minimality and reducibility of model theories in circumscription.