This chapter prepares the way for the purpose of the book, to use war as a case study for the claim that in major respects, thinking based on Darwin’s ideas—“Darwinism”—has from the first functioned as a form of secular religion, a variety of humanism. Although natural selection makes it very implausible to claim that there is an inevitable evolutionary progression up to humankind, this has not stopped Darwinians, from Darwin himself through to people like Edward O. Wilson today, seeing such progress and using this belief as a peg on which to hang social and moral views, in major respects alternatives to the social and moral views of Christianity. Often, as in the case of Julian Huxley, the intent to produce an alternative religion is made explicit. Rival views on the illicit use of seminal fluid are used as an illustration. For Christians, through self-abuse, it leads to degeneration. For Darwinians, through the failures of the sexually profligate, it leads to advance.