This is an entirely new translation of one of the fundamental works in the development of the study of language. Published in 1836, it formed the general introduction to Wilhelm von Humboldt's three-volume treatise on the Kawi language of Java. It is the final statement of his lifelong study of the nature of language, and presents a survey of a great many languages, exploring ways in which their various grammatical structures make them more or less suitable as vehicles of thought and cultural development. Empirically wide-ranging - von Humboldt goes far beyond the Indo-European family of languages - it remains one of the most interesting and important attempts to draw philosophical conclusions from comparative linguistics.