Many writers have addressed the similarities and differences between the analytical approaches of Marx and Veblen. The crucial concerns in these interpretations center on Darwinian evolution and the analysis of capitalism. By focusing on the analysis of capitalism, most Marxists have found considerable compatibility between Veblen's writings and those of Marx. Many institutionalists, on the other hand, have tended to stress the Darwinian content of both Veblen and Marx and have found Marx's analysis decidedly inferior to Veblen's. It is argued that it was Engels rather than Marx who attempted to incorporate Darwin into Marxism. As a consequence, Engels is compared with Veblen and the attempts of both writers to develop a Darwinian content to their analytical approaches are found to lead to a common bond, namely the stress on procreation.