structuredependent

Structuredependent is a term used in linguistics to describe the property of certain grammatical operations that rely on the hierarchical organization of a sentence rather than on the linear order of its words. In generative grammar, structure-dependent rules are those whose application depends on the syntactic configuration of constituents such as clauses and phrases. This contrasts with linear or purely string-based rules that would operate solely on the sequence of words.

Historically, structure dependence was highlighted by Noam Chomsky as part of an argument that grammar cannot be fully captured by simple, linear rewriting rules. He showed that certain transformations, such as forming questions by moving a wh-phrase, cannot be predicted by linear patterns alone; they depend on the underlying structure of the sentence. The principle predicts which extractions are allowed based on hierarchical relations, not just the order of words.

In practice, the concept has become a foundational assumption in many modern theories of syntax. It informs how linguists describe movement, binding, and other relations that cross clause boundaries. Structure dependence also has implications for psycholinguistics and language acquisition, where evidence from processing and learning tends to favor sensitivity to hierarchical structure over linear string heuristics.

Critically, some contemporary models retain the core idea while recasting the formal machinery—such as into parameter settings, tree automata, or computational grammars—so that structure dependence remains a central test for theories of grammar and cognition.