Social Darwinism generally refers to the extension of Charles Darwin's theories of natural selection in EVOLUTION, as used in his Origin of Species (1859), into the realm of social relations. Darwin had not intended his theories to be extended by analogy into the examination of racial groups, societies or nations. But certain British and American social theorists, notably Herbert Spencer and William Graham Sumner, made the analogy. The result was a social theory that provided late Victorians with a "scientific" explanation and social justification of racial inequality, cultural exploitation and laissez-faire capitalist activity. Canada produced few such extreme social theorists during the Darwinian revolution. The critic William Dawson LESUEUR sought to explain the theories of both Darwin and Spencer to Canadians in the Canadian Monthly and National Review during the 1870s and 1880s, but he consistently rejected the metaphoric extension of Darwin's phrase into the study of society. The logic of Darwin's notion of competition within and between species led instead, he argued, to the necessity of mutual aid and co-operation. Other Canadian observers agreed, with the exception of Goldwin SMITH, whose social views were more akin to those of Spencer. The dependent nature of Canadian economic and political life pointed most Canadian commentators toward ideas similar to those of Peter Kropotkin in Mutual Aid, a Factor of Evolution (1902).