Although fluctuations in business activity and in the level of income and employment had been occurring since the beginning of merchant capitalism and were acknowledged by orthodox theorists, economists made no systematic attempts to analyze either depression or the business cycle until the 1890s. Heterodox theorists, the most important of whom was Marx, had pursued these issues with greater vigor. But Marx’s works were largely ignored by orthodox theory. Thus, until the last decade of the nineteenth century, orthodox economic theory consisted of a fairly well developed theoretical microeconomic structure explaining the allocation and distribution of scarce resources, a macroeconomic theory explaining the forces determining the general level of prices, and a loose set of notions concerning economic growth. Prior to 1890, orthodox “work on depressions and cycles had been peripheral and tangential