Abstract

Based on a formal analysis of the operations Merge and Move, I provide a computational answer to the question why Move might be an integral part of language. The answer is rooted in the framework of subregular complexity, which reveals that Merge is most succinctly analyzed in terms of the formal class TSL. Any cognitive device that can handle this level of complexity also possesses sufficient resources for Move. In fact, Merge and Move are remarkably similar instances of TSL. Consequently, Move has little computational or conceptual cost attached to it and comes essentially for free in any grammar that expresses Merge as compactly as possible.