We prove two properties of logic programs under the answer set semantics that may be useful in connection with applications of logic programming to representing causality and to planning. One theorem is about the use of disjunctive rules to express that an atom is exogenous. The other provides an alternative way of expressing that a plan does not include concurrently executed actions.

PS

In Logic Programming and Non-monotonic Reasoning: Proceedings Fifth Int'l Conf. (Lecture Notes in Artificial Intelligence 1730), pp. 107-116 1999.

@INPROCEEDINGS{erd99, title={Transformations of Logic Programs Related to Causality and Planning}, author={Esra Erdem and Vladimir Lifschitz}, booktitle={Logic Programming and Non-monotonic Reasoning: Proceedings Fifth Int'l Conf. (Lecture Notes in Artificial Intelligence 1730)}, pages={107-116}, url="http://www.cs.utexas.edu/users/ai-lab?erd99", year={1999} }