According to Lera Boroditsky, "the languages we speak not only reflect or express our thoughts, but also shape the very thoughts we wish to express. The structures that exist in our languages profoundly shape how we construct reality, and help make us as smart and sophisticated as we are." As one familiar with multiple languages, I am quite sympathetic to this viewpoint. This is largely why every vanishing language feels like a great loss to me. In an exchange with Joshua Knobe, Ms. Boroditsky sheds more light on the topic (via Cognition and Culture).