This paper addresses the puzzle of choosing among competing syntactic theories, which are contrasting theories that can nevertheless all properly account for the utterances of some language. To do so, I develop an evaluation metric that is based on language learnability and acquisition. In particular, such an acquisition-based metric considers speed of acquiring a target grammar, as well as relative accuracy of acquisition. In applying such a metric, I propose using the kinds of novel data that can be generated via computational modeling for syntactic learning. I then demonstrate how this evaluation metric can be used effectively by reporting on learning simulations for a case study, which focuses on two competing theories that arise in the literature for verb raising in Swedish. (Ewha Womans University)