There are a variety of phonological asymmetries exhibited by segments which appear in perceptually or psycholinguistically prominent positions such as roots, root-initial syllables, stressed syllables, and syllable onsets. In such positions, segmental or featural contrasts are often maintained, though they may be neutralized in non-prominent positions. Segments in prominent positions frequently trigger phonological processes such as assimilation, dissimilation and vowel harmony; conversely, they often block or resist the application of these processes. The goal of this dissertation is to develop a theory of positional faithfulness which will both generate and explain the range of positional asymmetries attested in natural language phonology.
Chapter 1 introduces the notion of positional privilege, as well as the fundamental aspects of Optimality Theory. Positional faithfulness constraints are introduced and demonstrated in an analysis of onset/coda asymmetries in Catalan voice assimilation. I argue that positional faithfulness provides an explanation for the attested onset/coda asymmetries that is not afforded by licensing alternatives.
Faithfulness in root-initial syllables, a position in which prominence derives largely from psycholinguistic (rather than phonetic) properties, is considered in Chapter 2. Particular attention is given to the analysis of vowel harmony in Shona, and to the phonology of consonantal place in Tamil.
Chapter 3 is devoted to the domain of stress, showing once again that positional faithfulness constraints unify and explain a wide range of phonological asymmetries associated with the positional prominence. The core of the chapter is an analysis of nasal harmony in Guarani; vowel reduction in Catalan is also examined.
In Chapter 4, I turn to positional privilege effects which are sensitive to the distinction between root and affix. Such cases provide further support for positional faithfulness theory.
Finally, in Chapter 5, a different type of positional faithfulness effect, that of positional maximization, is examined. I argue that constraints which favor maximal packing of prominent constituents are necessary. Such constraints are crucial in cases of prominence-driven ambisyllabicity, as in Ibibio. Positional MAX constraints also account for the appearance of complex syllable margins in prominent positions, though complex margins may be excluded elsewhere in the language.