@article {3152453, title = {Two adaptive logics of norm-propositions}, journal = {JOURNAL OF APPLIED LOGIC}, volume = {11}, number = {2}, year = {2013}, pages = {147{\textendash}168}, abstract = {

We present two defeasible logics of norm-propositions (statements about norms) that (i) consistently allow for the possibility of normative gaps and normative conflicts, and (ii) map each premise set to a sufficiently rich consequence set. In order to meet (i), we define the logic LNP, a conflict- and gap-tolerant logic of norm-propositions capable of formalizing both normative conflicts and normative gaps within the object language. Next, we strengthen LNP within the adaptive logic framework for non-monotonic reasoning in order to meet (ii). This results in the adaptive logics LNPrLNPr and LNPmLNPm, which interpret a given set of premises in such a way that normative conflicts and normative gaps are avoided ‘whenever possible’. LNPrLNPr and LNPmLNPm are equipped with a preferential semantics and a dynamic proof theory.

}, issn = {1570-8683}, doi = {http://dx.doi.org/10.1016/j.jal.2013.02.001}, author = {Beirlaen, Mathieu and Stra{\ss}er, Christian} } @article {CJM:demi, title = {Tolerating Deontic Conflicts by Adaptively Restricting Inheritance}, journal = {Logique et Analyse}, volume = {219}, year = {2012}, pages = {477-506}, abstract = {

In order to deal with the possibility of deontic conflicts Lou Goble developed a group of logics DPM that are characterized by a restriction of the inheritance principle. While they approximate the deductive power of standard deontic logic, they do so only if the user adds certain statements to the premises. By adaptively strengthening the DPM logics, this paper presents logics that overcome this shortcoming. Furthermore, they are capable of modeling the dynamic and defeasible aspect of our normative reasoning by their dynamic proof theory. This way they enable us to have a better insight in the relations between obligations and thus to localize deontic conflicts.

}, author = {Stra{\ss}er, Christian and Meheus, Joke and Beirlaen, Mathieu} } @phdthesis {PhD_Mathieu, title = {Tolerating Normative Conflicts in Deontic Logic.}, year = {2012}, month = {September 13}, publisher = {Ghent University}, type = {phd}, author = {Beirlaen, Mathieu} } @incollection {Beirlaen2012a, title = {Towards More Conflict-Tolerant Deontic Logics}, booktitle = {Logic, Philosophy and History of Science in Belgium II}, year = {2012}, pages = {1-8}, publisher = {Koninklijke Vlaamse Academie van Belgi{\"e}}, address = {Brussel}, abstract = {

In Ethical Consistency, Bernard Williams vindicated the possibility of moral conflicts; he proposed to consistently allow for the presence of such conflicts within the logic of ought. In determining the nature of moral conflict, Williams stressed its contingency. In this paper, Williams’ characterization of moral conflict is defended. However, Williams’ solution for consistently allowing for such conflicts within the logic of ought is shown to be too crude. Whereas Williams rejects all applications of the agglomeration rule in the logic of ought, it is shown that a more sophisticated approach is needed. An alternative solution is presented in which the application of the agglomeration rule is made conditional upon the principle that" oughtimplies can."

}, author = {Beirlaen, Mathieu}, editor = {Van Kerkhove, Bart and Libert, Thierry and Vanpaemel, Geert and Marage, Pierre} } @article {strasser2010towards, title = {Towards more conflict-tolerant deontic logics by relaxing the interdefinability between obligations and permissions}, year = {2010}, abstract = {

While conflict-tolerant logics (CTDLs) usually allow for obligation- obligation conflicts, they fall short of tolerating obligation-permission con- flicts (OP-conflicts) of the type OA \&\#8743; P\&\#172; A. Moreover, for the sake of conflict-tolerance these logics usually do not validate the very intuitive principle (D), OA \&\#8835; PA. We demonstrate in this paper that by relaxing the interdefinability between obligations and permission PA =df \&\#172;O\&\#172;A that is characteristic for most deontic logics, the logics get more conflict-tolerant since they allow for OP-conflicts. Moreover, this way they can be equipped with (D) without the need to sacrifice conflict-tolerance. In this paper we offer a generic procedure that transforms a given CTDL into a logic that tolerates OP-conflicts and validates (D).

}, author = {Stra{\ss}er, Christian and Beirlaen, Mathieu} }