In this book, Katz offers a new reading of Karl Marx's theory of history. The book re-examines two incompatibile versions of historical materialism: one ascribes the primary cause of historical development to technological progress, the other to class struggle. Katz argues that these versions are inadequate, both as interpretations of Marx's theory and as explanations of the problems of historical change. His study distinguishes three different levels of analysis. The first level is Marx's own summaries of historical materialism, which typically award causal primacy to technology. The second level is Marx's historical studies of feudalism and the transition to capitalism, where class and class struggle play a central role. The third level is the modern debate on the transition from feudalism to capitalism. The history of this transition is chosen by Katz as an empirical test of Marxian theory because it is the principal source from which Marx developed the concepts for interpreting the dynamics of crisis in modes of production. By establishing a reciprocal movement between the respective explanatory roles of technology and class struggle on the one hand, and the historical record on the other, Katz evaluates their relative contributions to an understanding of the supersession of feudalism by capitalism. The result is a reconstruction of Marx's theory of radical social change, one which is "historically and theoretically more tenable." The book's first two chapters develop and contrast the two dominant principles of historical causality in Marx's work: class struggle and the development of technology. Subsequent chapters explore the history of feudalism's decline and final disintegration, and its replacement by capitalism, providing a critical analysis of Marx's theory of history.