This dissertation investigates fixed word order phenomena in 'free' word order languages and their consequences for linguistic theory. Ashas long been observed, languages with flexible word order, in certain circumstances, show 'freezing' effects, whereby only a canonical word order is possible. I propose new generalizations to explain the two types of freezing effects, namely markedness reduction in marked grammatical contexts and the emergence of the unmarked, and show that these pervasive patterns of markedness are incompatible with the classical conception of grammar within generative linguistics where principles of universal grammar (UG) are both universal and inviolable. The analysis I develop here, set within the framework of Optimality-theoretic Lexical-Functional Grammar, captures the universal basis of word order freezing and its parallels to markedness reduction and emergence of the unmarked effects observed in other systems for argument expressions and in other components of grammar,while at the same time allowing for crosslinguistic variation. The first part of the dissertation shows how the Optimality-theoretic account, based on the interaction between markedness constraints derived through harmonic alignment of prominence hierarchies and other constraints on word order, naturally captures the pattern of universal markedness and the basic generalization that highly marked argument types occur only in unmarked position in Hindi and Korean: in these two languages, noncanonical orderings are preferred options for marking a special information structure. However, in the special case of prominence mismatch, they are replaced by the less marked, canonical order. This is due to the ranking in which the markedness constraints banning marked argument types in the marked positions dominate the information structuring constraints which favor realization of contrasting discourse prominence of arguments. Beyond providing a specific analysis for the freezing effects in Hindi and Korean, I show how the constraint system I develop can be employed to explain markedness reduction in the systems of contrast in other domains of morphosyntax. In the second part, the model is extended to comprehension as well as production, demonstrating further advantages of the optimization-based approach to argument expression. It is shown that by defining grammaticality in terms of bidirectional optimization, we can account for the word order freezing effect as the emergence of the unmarked incomprehension grammar, in terms of the same set of markedness and faithfulness constraints that are independently motivated for a production-based optimization account of case patterns and constituent ordering. Along with other optimization-based approaches to morphosyntax, the present study contributes solid evidence for fundamental structural parallels between phonology and syntax, and raises questions whether the arbitrary separation of linguistic phenomena and performance-related phenomena has any systematic theoretical and empirical significance.Ph.D
