Prohairetic Deontic Logic (PDL)

In this paper we introduce Prohairetic Deontic Logic, a preference-based dyadic deontic logic.An obligation `A should be (done) if B is (done)' is true if (1) no $\neg$ A/\B is preferred to anA/\B and (2) the preferred B are A. We show that this mixed representation solves severalproblems of deontic logic. Moreover, we discuss the relation between preference-based deonticlogic and qualitative decision theory