Several people discussed the evolution of humans. Among them were Thomas Huxley and Charles Lyell. Huxley convincingly showed many of the similarities and differences between humans and apes in his 1863 book "Evidence as to Man's Place in Nature". When Darwin published his own book on the subject, "The Descent of Man, and selection in relation to sex", the idea of human evolution was already well-known. The theory was controversial. Even some of Darwin's supporters (such as Alfred Russel Wallace and Charles Lyell) did not like the idea that human beings have evolved their impressive mental capacities and moral sensibilities through natural selection.