This article provides a critique of the theories that have been applied to second language acquisition in classroom settings. It discusses how theories from the 1950s based on behaviorism have been replaced by theories focusing on innateness, but neither have led to definitive answers or clear improvements in the classroom. The article outlines the philosophical underpinnings of influential theories proposed by Chomsky, Skinner, and Piaget. It then proposes an original theory for how language is acquired and how that could be applied to teaching, with the goal of avoiding past pitfalls. The key points are that theories of language acquisition have changed over time but not resolved fundamental questions, different theories are influenced as much by philosophy as research, and the article aims to offer