This paper discusses some key connections between Berkeley's reflections on language in the introduction to his Treatise on the Principles of Human Knowledge and the doctrines espoused in the body of that work, in particular his views on vulgar causal discourse and his response to the objection that his metaphysics imputes massive error to ordinary thought. I argue also that there is some mileage in the view that Berkeley's thought might be an early form of non-cognitivism.