Unstable surface correspondence as the source of local conspiracies

In this paper, we address parallelisms between local and long-distance effects in segmental phonology, focusing on the similarity conditions that trigger them. We take the view that both local and long-distance harmony and disharmony are consequences of segmental correspondence—namely, unstable surface correspondence—as modeled in Agreement by Correspondence theory (henceforth ABC; e.g., Walker 2000a, b; Hansson 2001; Rose and Walker 2004). The basic tenet of ABC is that properties of featural or structural similarity underlie interactions between segments; unstable surface correspondence is the situation in which segments are sufficiently similar to interact but too uncomfortably similar to stably coexist at a certain distance, thereby requiring repair via assimilation or dissimilation. This united view of local and non-local (dis)harmony offers an alternative to standard markedness constraints that have been invoked in Optimality Theory (OT; Prince & Smolensky 2004) to handle local assimilation and dissimilation effects. As our case study, we examine the classic nasal-consonant (NC) patterns that have played a key role in the development of OT. The paper is organized as follows. Section 2 introduces the ABC framework, as originally motivated by long-distance effects, and the idea of unstable surface correspondence. Section 3 presents case studies from local NC patterns and argues that local segmental interactions can also, like long-distance effects, be understood as consequences of unstable surface correspondence relationships. Section 4 discusses the typological advantages of an ABC account of NC patterns. Section 5 presents parallels between local and non-local (dis)harmony processes under the united approach that ABC offers.