quality:corruption
Application of theory to humans, and role of teleology in evolution

In 1864, Wallace published a paper, "The Origin of Human Races and the Antiquity of Man Deduced from the Theory of 'Natural Selection ' ", applying the theory to humankind. Darwin had not yet publicly addressed the subject, although Thomas Huxley had in Evidence as to Man's Place in Nature. Wallace explained the apparent stability of the human stock by pointing to the vast gap in cranial capacities between humans and the great apes. Unlike some other Darwinists, including Darwin himself, he did not "regard modern primitives as almost filling the gap between man and ape". He saw the evolution of humans in two stages: achieving a bipedal posture that freed the hands to carry out the dictates of the brain, and the "recognition of the human brain as a totally new factor in the history of life". Wallace seems to have been the first evolutionist to see that the human brain effectively made further specialisation of the body unnecessary. Wallace wrote the paper for the Anthropological Society of London to address the debate between the supporters of monogenism, the belief that all human races shared a common ancestor and were one species, and the supporters of polygenism, who held that different races had separate origins and were different species. Wallace's anthropological observations of Native Americans in the Amazon, and especially his time living among the Dayak people of Borneo, had convinced him that human beings were a single species with a common ancestor. He still felt that natural selection might have continued to act on mental faculties after the development of the different races; and he did not dispute the nearly universal view among European anthropologists of the time that Europeans were intellectually superior to other races. According to political scientist Adam Jones, "Wallace found little difficulty in reconciling the extermination of native peoples with his progressive political views". In 1864, in the aforementioned paper, he stated "It is the same great law of the preservation of favored races in the struggle for life, which leads to the inevitable extinction of all those low and mentally undeveloped populations with which Europeans come in contact." He argued that the natives die out due to an unequal struggle.

Shortly afterwards, Wallace became a spiritualist. At about the same time, he began to maintain that natural selection could not account for mathematical, artistic, or musical genius, metaphysical musings, or wit and humour. He stated that something in "the unseen universe of Spirit" had interceded at least three times in history: the creation of life from inorganic matter; the introduction of consciousness in the higher animals; and the generation of the higher mental faculties in humankind. He believed that the raison d'être of the universe was the development of the human spirit.

While some historians have concluded that Wallace's belief that natural selection was insufficient to explain the development of consciousness and the higher functions of the human mind was directly caused by his adoption of spiritualism, other scholars have disagreed, and some maintain that Wallace never believed natural selection applied to those areas. Reaction to Wallace's ideas on this topic among leading naturalists at the time varied. Lyell endorsed Wallace's views on human evolution rather than Darwin's. Wallace's belief that human consciousness could not be entirely a product of purely material causes was shared by a number of prominent intellectuals in the late 19th and early 20th centuries. All the same, many, including Huxley, Hooker, and Darwin himself, were critical of Wallace's views.

As the historian of science and sceptic Michael Shermer has stated, Wallace's views in this area were at odds with two major tenets of the emerging Darwinian philosophy. These were that evolution was not teleological (purpose-driven), and that it was not anthropocentric (human-centred). Much later in his life Wallace returned to these themes, that evolution suggested that the universe might have a purpose, and that certain aspects of living organisms might not be explainable in terms of purely materialistic processes. He set out his ideas in a 1909 magazine article entitled The World of Life, later expanded into a book of the same name. Shermer commented that this anticipated ideas about design in nature and directed evolution that would arise from religious traditions throughout the 20th century.