1 A Simple Proof that Optimality Theory is Computationally Intractable

Adapting arguments from Eisner (1997, 2000), this remark provides a simple proof that the generation problem for Optimality Theory (OT, Prince and Smolensky 2004) is NP-hard. The proof needs only the binary evaluation of constraints and uses only constraints generally employed in the OT literature. In contrast, rule-based derivational systems are easily computable, belonging to the class of polynomial time algorithms, P (Eisner 2000).