A Rule-ordering Theory of Blocking in Nonderived Environments

In Nonderived Environment Blocking (NDEB), a phonological process applies across morpheme boundaries or morpheme-internally when fed by another phonological process but is otherwise blocked from applying. NDEB poses a challenge to both rule-based phonology and Optimality Theory: if P is a process that is blocked in nonderived environments, the challenge in both frameworks is to partition the set of environments of application of P into two subsets – corresponding to derived and nonderived environments – and block the application of the process precisely in nonderived environments. My goal in this paper is to show that NDEB can be reduced to rule ordering. I will do so by presenting a rule-ordering theory of NDEB that uses morpheme structure rules. Every rule P that is blocked in nonderived environments will be ordered after a morpheme structure rule R that removes P’s environments of application. Since morpheme structure rules apply to URs of individual morphemes (which correspond to nonderived environments), R will prevent P from applying precisely in nonderived environments.