 Each of the distinctively deontic principles, \(\OB\)-K, NC, and \(\OB\)-NEC are contestable, and we will consider criticisms of them in  Section 6.  However, to avoid immediate confusion for those new to deontic logic, it is perhaps worth noting that \(\OB\)-NEC is generally deemed a convenience that, among other things, assures that SDL is in fact one of the well-studied normal modal  logics.[20]  Few have spilled blood to defend its cogency substantively, and often these practical compromises are wise, especially in early stages of research.