On the Origin of Species the manuscript for his "big book" on Species, "Natural Selection". By mid March 1859 Darwin's abstract had reached the stage where he was thinking of early publication; Lyell suggested the publisher John Murray, and met with him to find if he would be willing to publish. On 28 March Darwin wrote to Lyell asking about progress, and offering to give Murray assurances "that my Book is not more "un"-orthodox, than the subject makes inevitable." He enclosed a draft title sheet proposing "An abstract of an Essay on the Origin of Species and Varieties Through natural selection", with the year shown
On the Origin of Species Darwin had been somewhat coy about human origins, not identifying any explicit conclusion on the matter in his book, he had dropped enough hints about human's animal ancestry for the inference to be made, and the first review claimed it made a creed of the "men from monkeys" idea from "Vestiges". Human evolution became central to the debate and was strongly argued by Huxley who featured it in his popular "working-men's lectures". Darwin did not publish his own views on this until 1871. The naturalism of natural selection conflicted with presumptions of purpose in nature and while this could be