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Using abduction in ALP it is possible to conclude <syntaxhighlight inline lang="prolog">canfly(mary)</syntaxhighlight> under the assumption <syntaxhighlight inline lang="prolog">normal_flying_bird(mary)</syntaxhighlight>. The conclusion can be derived from the assumption because it cannot be shown that the integrity constraint is violated, which is because it cannot be shown that <syntaxhighlight inline lang="prolog">wounded(mary).</syntaxhighlight> In contrast, it is not possible to conclude <syntaxhighlight inline lang="prolog">canfly(john),</syntaxhighlight> because the assumption <syntaxhighlight inline lang="prolog">normal_flying_bird(john)</syntaxhighlight> together with the fact <syntaxhighlight inline lang="prolog">wounded(john)</syntaxhighlight> violates the integrity constraint. This manner of reasoning in ALP simulates reasoning with negation as failure.<ref>Eshghi, K. and Kowalski, R.A., 1989, June. Abduction Compared with Negation by Failure. In ICLP (Vol. 89, pp. 234-255).</ref>
Conversely, it is possible to simulate abduction in ALP using negation as failure with the [[stable model semantics]].<ref>Kakas, A.C., Kowalski, R.A. and Toni, F., 1992. Abductive logic programming. Journal of logic and computation, 2(6), pp.719-770.</ref> This can be done by adding, for every abducible predicate <syntaxhighlight inline lang="prolog">p,</syntaxhighlight> an additional contrary predicate <syntaxhighlight inline lang="prolog">negp,</syntaxhighlight> and a pair of clauses:
<syntaxhighlight lang="prolog">
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