In his fourth edition of Éléménts d'économie politique pure (1900), León Walras introduced the device of written pledges to eliminate path dependency: sellers of products and services write out commitments to supply certain quantities at suggested prices with no commodities actually produced and supplied until a set of prices is found at which supply and demand are equal simultaneously in every market. This brought about very serious alterations to the character of the book. Unfortunately, these changes resulted in an incomplete, internally contradictory, and occasionally incoherent text. This translation, therefore, by two leading scholars of León Walras' work, Donald A. Walker and Jan van Daal, revisits the third edition of this seminal work, including Walras' brilliant explanation of his comprehensive model, with all its richness derived from reality. Growing research into Walras' work indicates that it was this third edition that contained his best theoretical research and a translation of this edition of the book is now a necessity.

This is an English translation of the third edition (1896) of León Walras' Elements of Theoretical Economics. The translators of the work undertook this project for three reasons. First, this edition is Walras's best theoretical work. Second, the two subsequent editions contain new elements that spoil his previous work; furthermore, important parts of the third edition do not appear in the subsequent editions. Third, William Jaffé's translation (1954) of the last edition is now outdated in the light of recent research on Walras's ideas; furthermore, Jaffé's terminology in the parts shared by the third and subsequent editions is not always accurate.

Elements of Pure Economics was one of the most influential works in the history of economics, and the single most important contribution to the marginal revolution. Walras' theory of general equilibrium remains one of the cornerstones of economic theory more than 100 years after it was first published.

In order to understand the various strands of general equilibrium theory, why it has taken the forms that it has since the time of Léon Walras, and to appreciate fully a view of the state of general equilibrium theorising, it is essential to understand Walras's work and examine its influence. The first section of this book accordingly examines the foundations of Walras's work. These include his philosophical and methodological approach to economic modelling, his views on human nature, and the basic components of his general equilibrium models. The second section examines how the influence of his ideas has been manifested in the theorising of his successors, surveying the models of theorists such as H. L. Moore, Vilfredo Pareto, Knut Wicksell, Gustav Cassel, Abraham Wald, John von Neumann, J. R. Hicks, Kenneth Arrow, and Gerard Debreu. The treatment also examines models of many types in which Walras's influence is explicitly acknowledged.