Being concerned with representation, this book is about an idea, a concept, a word. It is primarily a conceptual analysis, not a historical study of the way in which representative government has evolved, nor yet an empirical investigation of the behavior of contemporary representatives or the expectations voters have about them. Yet, although the book is about a word, it is not about mere words, not merely about words. For the social philosopher, for the social scientist, words are not "mere"; they are the tools of his trade and a vital part of his subject matter. Since human beings are not merely political animals but also language-using animals, their behavior is shaped by their ideas. What they do and how they do it depends upon how they see themselves and their world, and this in turn depends upon the concepts through which they see. Learning what "representation" means and learning how to represent are intimately connected. But even beyond this, the social theorist sees the world through a network of concepts. Our words define and delimit our world in important ways, and this is particularly true of the world of human and social things. For a zoologist may capture a rare specimen and simply observe it; but who can capture an instance of representation (or of power, or of interest)? Such things, too, can be observed, but the observation always presupposes at least a rudimentary conception of what representation (or power, or interest) is, what counts as representation, where it leaves off and some other phenomenon begins. Questions about what representation is, or is like, are not fully separable from the question of what "representation" means. This book approaches the former questions by way of the latter.