“Evolution is promoted by its practitioners as more than mere science. Evolution is promulgated as an ideology, a secular religion–a full-fledged alternative to Christianity, with meaning and morality. I am an ardent evolutionist and an ex-Christian, but I must admit that in this one complaint–and Mr. Gish is but one of many to make it–the literalists are absolutely right. Evolution is a religion. This was true of evolution in the beginning, and it is true of evolution still today.”
– Michael Ruse, How evolution became a religion
Darwin showed that material causes are a sufficient explanation not only for physical phenomena, as Descartes and Newton had shown, but also for biological phenomena with all their seeming evidence of design and purpose. By coupling undirected, purposeless variation to the blind, uncaring process of natural selection, Darwin made theological or spiritual explanations of the life processes superfluous. Together with Marx's materialistic theory of history and society and Freud's attribution of human behavior to influences over which we have little control, Darwin's theory of evolution was a crucial plank in the platform of mechanism and materialism…
-Douglas Futuyma's Evolutionary Biology (1998, 3rd Ed., Sinauer Associates), p. 5