Unless you are in the scientific field, a good student, or someone that knows their history fairly well, you probably aren't familiar with the name, Alfred Russel Wallace, whereas the name, Charles Darwin, is a name that most everyone is both familiar with as well as having a general idea of the fact that he is the man behind the origin of theory of evolution and natural selection. The thing of it is, though, although Darwin seemingly gets all the accolades, each biologist actually independently came up with the theory of natural selection, although there were differences between the two, with Wallace emphasizing more the adaption of species to their environment, as compared to Darwin and his belief in the survival of the fittest, as well as species changing via sexual selection. That said, the two biologists had their papers read at the Linnean Society of London in 1858, to which the society stated that, "The gentlemen having, independently and unknown to one another, conceived the same very ingenious theory to account for the appearance and perpetuation of varieties and of specific forms on our planet…"
Nowadays, if this sort of thing would have happened, as in a "co-discovery" and "independent," it might have well have degenerated quickly into an all-out fight as to who was first, original, and so forth, but fortunately those Victorian times were different and far more genteel. The fact of the matter is that Wallace was entirely gracious to Darwin, his social superior in class conscious England, but at the same time Wallace never felt upstaged or in egotistical need for his name to be emblazoned in glory. Above all else, Wallace was a colleague, a scientist, a biologist, a naturalist, as well as being a reserved man, who felt more comfortable standing behind "Darwinism" than being front and center with it, with Wallace, himself, clearly being a man who appreciated those that advanced science for the benefit and education of mankind.
The theory of evolution, however, was something that for a religious society, especially those of a religious stripe that took their Scripture as the literal truth, was both of momentous as well as terrifying importance for the meaning of mankind, itself. For Darwin, man, was subject to the same laws of other species, to which mankind must therefore too have descended from earlier species, which in our case meant the great ape family, signifying that man, himself, had evolved from apes. It was that type of admission, or theory that would obviously create havoc for both the meaning of man, as well as to man's status in the world. That is to say, if man was merely a creature that had somehow evolved over time, this could conceivably be also seen as a stipulation that God was either irrelevant or non-existent, and that therefore it then followed that the Bible, itself, was merely a fable.
While we cannot know for a certainty what Darwin's enlightened views were on God, he self confessed to being an agnostic; whereas Wallace was a devout Spiritualist, freely admitting that given the right circumstances the living could communicate with those that were physically dead as well as humans having the innate ability to communicate or to become attuned with the Higher Intelligence. This meant that Wallace knew that the evolution of mankind which gave man the ability to think, to reason, to communicate, the knowledge of mathematics and symbols, space and time, as well as our innate code and understanding of ethics, moralityand natural law, could only have come to us via a Higher power. Because Wallace knew this, he intuited and understood that each human life, without exception, has intrinsic value as well as being given a free will, so that each of us is ultimately the sum of what we have accomplished by our conduct and interaction here, and that therefore our evolutionary spiritual progress was written by our deeds which we carried with us upon our departure from this material plane.