 Among his published writings only the Ideen zu einem Versuch die Grenzen der Wirksamkeit des Staats zu bestimmen (The Spheres and Duties of Government) 1792, the Aesthetische Versuche I (Essays on Aesthetics I) 1799, Prüfung der Untersuchungen über die Urbewohner Hispaniens (On the Early Inhabitants of Spain) 1821, and the Kawi-Einleitung (Introduction to the Kavi Language) 1836, constitute complete works in the traditional sense. The majority of his writings consist of essays, articles or presentations produced for specific occasions on the one hand and of a large body of sketches, studies, notes, expositions and entire treatises on the other. Humboldt used the medium of writing as a vehicle of intellectual exploration to untangle the complex and diverse aspects of a specific problem or set of problems rather than attempting to state a fixed and definite position or opinion, and he would often bring to bear different view-points onto the matter at hand and utilize varying formulations. It is characteristic of his intellectual style that he would with consistent philosophical and methodological astuteness develop a specific type of questioning that made it possible for him to bring to view particular phenomena or sets of problems in their inherent complexity. What lends a sense of unity to the large variety of his writings devoted to so many different domains of knowledge, is his consistency in articulating questions, in applying a specific viewpoint and perspective, and a recurring use of specific key concepts and their concomitant terminology.