What is the nature of the intellectual enterprise - general equilibrium analysis - that so many economists regard as the centerpiece of their discipline? In this book, Roy Weintraub considers both the modern history of the analysis, and the methodological puzzles that it, and mathematical economic theory in general, pose. Professor Weintraub argues that previous writings on the history and method of general equilibrium theory have been curiously biased and misleading. He provides a clear and careful presentation of the development of the theory from the 1930s through to the Arrow-Debreu work of the 1950s. This historical analysis is the centre of the book: a case study which permits the author to justify the status of general equilibrium theory in economics and the activity in which economic theorists engage. He argues that previous methodological investigations have been distorted by their use of inappropriate models taken from the philosophy of science that were developed to appraise work in the physical sciences.