Title Introducing Grades in Deontic Logics Publication Type Conference Paper Year of Publication 2008 Authors Dellunde P, Godo L Editor van der Meyden R, eds.) Lvan der To Conference Name Ninth International Conference on Deontic Logic in Computer Science (DEON'08) Volume 5076 Edition Ron van der Meyden and Leon van der Torre Publisher Springer-Verlag Conference Location Luxembourg Pagination 248-262 Date Published 15/07/2008 Abstract In this paper we define a framework to introduce gradedness in Deontic logics through the use of fuzzy modalities. By way of example, we instantiate the framework to Standard Deontic logic (SDL) formulas. Given a deontic formula $Φ\in SDL$, our language contains formulas of the form $\overline{r} \to NΦ$ or $\overline{r} \to PΦ$, where $r \in [0, 1]$, expressing that the preference or probability degree respectively of a norm Φ is at least $r$. We present sound and complete axiomatisations for these logics.