This introduction aims at presenting an overview of the content of the book. For each chapter it presents the problem, the model and the main results. Whenever possible, an analysis or even a sketch of the proof is given within an appropriately simplified version of the model. The information can also be read by section, each section, or overview, acting as an extended introduction to the corresponding chapter. Finally, it provides a summary to which the reader may want to refer after reading the whole book. Naturally, these are not mutually exclusive uses of the Introduction!

As stressed in the foreword, and as emphasized in the title, the monograph is a contribution to pure theory. As such, it aims at exploring the logic of an abstract model, the stylized features of which describe a (so-called) polar world. Within such a model - again ‘théorie pure’ a la Walras - derivations and also comments concern the polar world under consideration and not the specific issues, debates, and controversies that the analysis of the polar world aims at clarifying. Although the separation of theory and policy analysis is a standard modern procedure, it has the inconvenience of making the theorist’s logic and motivation more obscure to practitioners than it should be. As an attempt to overcome this difficulty, at the beginning of each overview a subsection, entitled ‘Motivation of the chapter: issues, studies and debates’, sketches a description of background materials, underlying issues, related applied studies and possible controversies that put each chapter in a better perspective. Throughout the book bibliographical references are kept to a minimum. In fact, they are gathered as much as possible in the bibliographical note appearing at the end of each chapter.