 Corresponding to simple seriality for SDL (that there is always an \(i\)-acceptable world), we assume what I will call “strong seriality” for Kd: for every world \(i\), there is an \(i\)-accessible world that is among those where all normative demands are met. In other words, for every world \(i\), the intersection of the \(i\)-accessible worlds with DEM is non-empty. Given the truth conditions for \(d\), strong seriality validates \(\Diamond d\), ensuring that for any world \(i\), there is always some \(i\)-accessible world where \(d\) is true: