Enclisis in Northwestern Iberian languages: A diachronic theory

This dissertation studies the evolution of clause derivations in the history of Northwestern Iberian Languages--Galegan, Leonese, Portuguese and Spanish. It is devoted to structures in which weak proforms play a distinctive role in triggering the spell-out of derivations. The goal is to show that the transformations a language undergoes in the course of time provide information about what is "core syntax", which is considered to be the conjunction of "productive syntax" and what will be referred to as "back syntax" or "inherited syntax". The fact that there exist two separate components of "core syntax" is not evident to native speakers, who cannot distinguish between them. A major consequence of the fact that native speakers cannot distinguish them is that both types of syntax contribute differently to the derivations in the model proposed, which is not incompatible with current theories of grammar based on feature checking. The contribution of inherited syntax is encoded in a morphosyntactic interface called Interface-L, through a "shrinking derivation" mechanism.;The thesis is that pronominal clitics and verbs contribute to sentence formation independently of each other, from the "initial state" of the languages under study onwards. Since clitics can be computed very late, as an extreme value in the derivation, this type of derivation has sometimes been confused with others based on a V2 derivation. When clitics and verbs start participating together in driving the derivation, the original type of computation becomes obsolete.;The prosodic deficiency of clitics must not be interpreted as a syntactic deficiency. It is shown that some changes in the structure of languages are due to independent and indirect factors that extremely reduce the power of quantificational studies. Specific modules of the proposed model of grammar are shown to be responsible for particular changes. The model is compatible with most current theories of language change, included a potential minimalist approach to language change and variation.;Dialectological studies also contribute to the knowledge of language change. The specific configurations used to test the thesis are: higher complex words, inverted conjugations, Interpolation, non-suppletive imperatives, pseudo-verbless configurations and subject expletives.