## Redundancy in Logic III: Non-Mononotonic Reasoning

**Paolo Liberatore**
*Artificial Intelligence*

Results about the redundancy of certain versions of
circumscription and default logic are presented. In particular,
propositional circumscription where all variables are minimized
and skeptical default logics are considered. This restricted
version of circumscription is shown to have the unitary
redundancy property: a CNF formula is redundant (it is
equivalent to one of its proper subsets) if and only if it
contains a redundant clause (it is equivalent to itself minus one
clause); default logic does not have this property in general.
We also give the complexity of checking redundancy in the
considered formalisms.

@article{libe-09,
title = {Redundancy in Logic III: Non-Mononotonic Reasoning},
year = {2008},
author = {Liberatore, Paolo},
journal = {Artificial Intelligence},
pages = {1317--1359},
number = {11},
volume = {172},
}

doi: 10.1016/j.artint.2008.02.003