Those philological studies which have been cultivated among polished nations, for their subserviency to literary taste, and their influence on the formation of correct habits of speaking and writing, have gradually suggested the more profound science of Universal Grammar. The business of this science is, not merely to dictate the best manner of connecting words with one another, but to investigate the origin of the various distinctions existing among them, and to discover in what instances these distinctions are dictated by occasional convenience or partial caprice, and in what instances they are essential to the purposes of language. By the aid of these investigations, philosophers have even hoped to trace some of the most important laws of human thought, and to obtain a solution of the most difficult problems of metaphysics. Some of the attempts made to realise these expectations have displayed great ingenuity; but, even with this qualification to recommend them, they have often failed to establish principles on a foundation sufficiently sure to preclude controversy.