The article aims to examine the scientific philosophical and ideological foundation of eugenics which had the status of applied science and a form of social movement in Western Europe and the United States in the late 19th - first half of the 20th centuries. I prove that evolutionism was the key scientific philosophical element of the foundation, primarily in its Darwinian version, interpreted in the context of metaphysical naturalism. Accordingly, the main ideological element was racism in its biological and social forms. Darwinism led to racism through the related ideas and views which also underpinned eugenics. I speak primarily about the radical biologization of a human being and the culture he or she created that flowed from Darwinism and strengthened it in turn. Although neither this nor any other version of evolutionary theory required such reductionism, they were closely interconnected. Other views of this kind included: (a) the insecurity of progress, which meant the possibility of a rollback towards the animal past; (b) the idea of an "anthropological stairs" which connected the lowest (anthropoid ape) and the highest (white educated inhabitant of Western civilization) points and was used to establish the measure of evolutionary development of a race, nation, class and individual; (c) the "scarce mentality" theorized by Thomas Malthus and well-responded by the spirit of developing capitalism, colonial expansion, and Protestant ethics; it painted the world as a field of incessant struggle for limited resources. The outlined complex of mythogenic views was part of the impending degeneration myth. I argue that the threat of far-fetched degeneration was the main engine of the eugenic movement. According to that myth, any highly civilized nation was to perish or degrade in a not too distant future if its biological life was allowed to take its course in the absence of large-scale measures to improve it. In conclusion, the "image" of eugenics as well as modes and forms of its presence in modern life and culture are discussed.
