"A Contribution to the Critique of Political Economy" by Karl Marx is a book published in 1859. Marx critiques the theories of leading classical economists like Adam Smith and David Ricardo to challenge the theoretical foundations of capitalism. Though much of its content was later incorporated into Capital, the book's Preface remains significant for presenting Marx's materialist conception of history—the theory that economic conditions shape society's political and ideological structures, rather than human consciousness determining social existence. (This is an automatically generated summary.)