This article explores parallels between Marx's and Schumpeter's theories of capitalist development, and discusses the relationship of these classical approaches to later constructivist theories of technological and organizational changes. It is suggested that Marxian and Schumpeterian ideas could be combined in a way which remedies the weaknesses of both sides, and provides a better understanding of the innovative dynamics of capitalism; such a synthesis could then be linked to a constructivist model of the rise and fall of economic `myths'.