P. d'Altan, J.-J. Ch. Meyer and R. J. Wieringa
We show that the distinction between ought to do and ought to be is relevant for at least some kinds of system specification and that, maintaining a certain degree of generality, it is possible to express both kinds of norms in one system without reducing one of them to the other or even assuming the existence of specific relations between them. We also show that by increasing the expressive power of the language by flagging violation atoms, we have to state relations connecting the violation of static constraints with that of dynamic ones.