In 1966, Paul Baran and Paul Sweezy published Monopoly Capital, a monumental work of economic theory and social criticism that sought to reveal the basic nature of the capitalism of their time. Their theory, and its continuing elaboration by Sweezy, Harry Magdoff, and others in Monthly Review magazine, infl uenced generations of radical and heterodox economists. They recognized that Marx's work was unfi nished and itself historically conditioned,...