This article presents a new interpretation of Marx's dialectical method. Marx conceived dialectics as a method for constructing a model of society. The way this model is developed is analogous to the way organisms develop according to the German embryologist Karl Ernst von Baer, and, indeed, Marx's theory of capitalism hinges on the same concept of Organisation that is found in teleomechanical biology. The strong analogy between pre-Darwinian biology and Marx's structure of argument shows that the analogy often supposed to (...) exist between Darwin and Marx is not relevant to Marx's theory of capitalism. (shrink)