This is a book on “equity in the civil law tradition” from the double perspective of legal history and comparative law. It is intended not only for civil lawyers who want to better understand the role and history of equity in their own legal tradition, but also – and perhaps more saliently – for common lawyers who are curious about why the history of equity has unfolded so differently on the continent of Europe and in Latin America. The author begins with the investigation of the philosophical foundations of the Western notion of equity in the teachings of Plato and Aristotle and of how their ideas affected the works of the great Attic orators (chapter 2). He then addresses the way in which Roman law turned this notion into a legal concept of considerable practical importance (chapter 3) and how it survived the fall of Rome and was later elaborated in the Middle Ages by civilists and canonists (chapter 4). Subsequently, the author analyses how the notion of equity was dealt with in the Modern Era by legal humanists, Protestant and Catholic theologians, scholars of the usus modernus pandectarum and of Roman-Dutch law, and then by legal rationalism and the philosophers of the Enlightenment (chapter 5). He then deals with the history of equity on the continent since the fragmentation of the ius commune and the codifications of the nineteenth century and with its reception in Latin America (chapter 6). Finally, the author offers some closing remarks on the fundamental equivocalness (or relativity, as some scholars put it) of the notion of equity in the civil law tradition today (conclusion).

That the recent turn in European Constitutional Review has effectively brought about a revolution in European law has been observed before. At issue are two major developments in European judicial review. On the one hand, the European Court of Human Rights has been collapsing traditional boundaries between constitutional law and private law with a series of decisions that effectively recognized the "horizontal" effect of Convention rights in the private sphere. On the other hand, the European Court of Justice has also given horizontal effect to fundamental liberties embodied in the Treaty on the Function of the European Union in a number of recent cases in a way that puts "established" boundaries between Member State and Union competences in question. This book takes issue with these developments by bringing to the fore a key issue that the horizontality effect debate has hitherto largely overlooked, namely, the question of sovereignty. It shows with detailed references to especially the American debate on state action and the German debate on Drittwirkung that horizontal effect cannot be understood consistently without coming to grips with the conceptions of state sovereignty that inform different approaches to horizontal effect.

This work for the first time brings together case law and law based on norms. It offers the reader a survey and a new explanation of evolutionary emergence of social contracts and constitutions in the European history, and should help to build a bridge between 'two cultures', science and humanities. It is addressed to philosophers of law, historians of law, theorists of science and social scientists.