If language change is constrained by grammatical structure, then synchronic assumptions have diachronic consequences. Theories of grammar can then in principle contribute to explaining properties of change, or conversely be falsified by historical evidence. This has been the main stimulus for incorporating historical linguistics into generative theorizing.

We propose an OT-theoretic typology of vowel harmony systems based on a comparative study of front/back harmony. Harmony processes are governed by a general constraint that imposes feature agreement on neighboring segments. Disharmonic (“neutral”) segments arise when this constraint is dominated by markedness constraints and/or by faithfulness constraints that govern segment inventories. These constraint interactions determine whether disharmonic segments are opaque or transparent, and fix the cross-linguistically diverse behavior of the latter. We make crucial use of two modes of local (...) constraint conjunction, which are already implicit in the current theory. Our proposal restricts this theory by eliminating the possibility of freely stipulating the domain of local conjunction. (shrink)

According to the neogrammarians and de Saussure, all linguistic change is either sound change, analogy, or borrowing.1 Meillet (1912) identified a class of changes that don’t fit into any of these three categories. Like analogical changes, they are endogenous innovations directly affecting morphology and syntax, but unlike analogical changes, they are not based on any pre-existing patterns in the language. Meillet proposed that they represent a fourth type of change, which he called GRAMMATICALIZATION. Its essential property for him was that (...) it gives rise to new grammatical categories — that is, to categories previously unexpressed in the language — and thereby transforms its overall system. (shrink)