This book outlines and illustrates a new approach to intellectual history - the history of "concepts". In distinction to the study of more traditional units of analysis, (authors, texts, traditions, discourses) conceptual history systematically combines the history of ideas and language with social history in such a way as to illustrate how changes in language both registered and shaped great transformations of government, society, economy, and mentality. With its origin in German social thought, and now gaining popularity in the US, this approach has affinities with some British intellectual history (Pocock, Skinner) and French discourse analysis, yet Richter carefully demonstrates how conceptual history makes important advances over each by focusing on the range of a terms's meaning, its changes, and its continuities, while avoiding pitfalls of deconstruction. This volume will be indispensable for historians of political and social thought, political and social philosophers, and those interested in the history of ideas.