The theological and sociological grounds behind Darwin's conversion from a creationist to evolutionist theory of mankind are analyzed along with the scientific theories of the two schools of thought
This great book shows how Darwin’s theory of evolution by natural selection rested on the a priori assumptions of 19th century scientific positivism. Science was increasingly being separated from theology ever since the 17th century and it eventually culminated in a complete separation, with the old “episteme” of including God as an explanation for the natural world being thrown out. Under the new positivism, only physical causes could be considered scientific. So in a sense, then change of epistemology was not based on reason, it was a completely arbitrary to not include God.
The book also highlights Darwin’s use of negative theology in his reasoning in the Origin. Far from being a purely positivist scientific work, the Origin is full of arguments about how God acts, or what God would or wouldn’t do. For instance, God wouldn’t create parasitical insects since it was morally wrong. But how does Darwin know this? Where did he get this information about how God acts in the world, or what God would or wouldn’t create? Not from any empirical scientific investigation, it solely based on Darwin’s conception of God. His conception of God is overly anthropomorphic (much like all deistic beliefs). Whatever God is, God is ultimately beyond all human conceptualization and the greatest Christian theologians throughout 2000 years of history have recognized this (St. Thomas Aquinas comes to mind).
My only complaint with the book is that the author claims that the Origin was the last of the scientific book in the world to mix science and theology. That is just flat out wrong and a false claim. You still find these types of negative theological arguments being made by evolutionary biologist today. Otherwise it was a great book on intellectual history, and Darwin’s lingering theism, and the changing from a God centered science to a purely naturalistic one (again, which was completely arbitrary).
Neal Gillespie's historical analysis of the triumph of Darwinism uses as a key element Michel Foucault's concept of the "episteme." An episteme is something of a communal worldview, a collective set of presuppositions about knowledge, its nature and its limits. It is analogous to and yet broader than Thomas Kuhn's use of "paradigm." The paradigm governs a specific field of science; an episteme, on the other hand, involves the idea of science itself, and what constitutes good science. "Paradigms guide research and epistemes provide them with the logic, metaphysics, and epistemology that make scientific work possible."
The nineteenth century saw the gradual decline of the creationist episteme in natural history and its gradual replacement by one of positivism until the transformation was complete at the dawn of the twentieth century. "The positivist limited scientific knowledge, which he saw as the only valid form of knowledge, to the laws of nature and to...natural causes exclusively. The creationist, on the other hand, saw the world and everything in it as being the result of direct or indirect divine activity." The switch from one episteme to another in the scientific community was not instantaneous, but first required the growth of positivism within creationism itself.
In the days of William Paley in the eighteenth century, the watchmaker argument was in vogue, where design was seen in the "contrivances" in nature, machine-like structures such as eyes and wings. At that time God's miraculous, purposeful activity was understood to be indispensible to a proper understanding of the natural world. However, even as the community of naturalists remained solidly in the creationist episteme, by the early nineteenth century positivism had crept into their thinking and changed the way they viewed their creationism. They no longer viewed God as a miracle-working designer but as the designer of the laws of nature. These laws were not autonomous but were guided by the Creator to permit the unfolding of creation over time. Though not subject to constant divine interference they were nevertheless tied to divine purpose. This was thought to be more worthy of God, more profound that he could steer the laws of nature to unfold creation, than that he had to constantly intervene with miracles.
The problem was, however, that when design was no longer located in contrivances themselves, but in the laws that led to the formation of these so-called contrivances, design lost the common-sense, intuitive appeal that it had formerly enjoyed. Abstracting design removed it from the everyday observations in science and really necessitated taking it on faith. Thus when Charles Darwin, who lacked the strong Christian commitment of his naturalist forerunners, published his Origin of Species in 1859, he saw only autonomous laws of nature and no need to postulate a designer for them. Perhaps he could grant God as some sort of first cause for these laws, but if there was a God he certainly wasn't currently involved with them.
Darwin as a positivist recognized that the rival creationist episteme was utterly incommensurable with his. Creationism, though it was becoming more and more naturalistic, would never become positivistic, because it would never surrender the role that theology played in biology. Special creationists who advocated direct intervention in nature by God, had by and large given way to providential evolutionists in the second half of the nineteenth century. They did not understand why Darwin would not countenance divine guidance of evolutionary processes; this lack of understanding showed that they did not grasp the change in episteme that was taking place under their very noses. Though creationism seemed to have moved much closer to the views of Darwin, there was still an unbridgeable gulf between them.
This explains why Darwin lashed out at special creation in the Origin to the extent that he did. He recognized that design and any form of divine guidance in biology made his mechanism of natural selection superfluous. The whole point of natural selection was to show that unguided natural processes could counterfeit the appearance of design. Clearly then, "the touchstone of positive biology, at bottom, was not law or natural causes, but the absence of conscious contrivance or purpose."
Those who made the epistemic switch to positivism found that more than their science was affected. "Just as science shifted from a theological ground to a positive one, so religion - at least among many scientists and laymen influenced by science - shifted from religion as knowledge to religion as faith....Christianity became hard to distinguish from theism and theism from a vague belief in some sort of spiritual dimension in life."
Darwin is unique among the giants in the hall of fame of science in that his fame arose when the theory for which he is famous, speciation through natural selection acting on random variations, was not generally accepted. Gillespie explains: "Darwin... found scientists becoming more and more positivistic, and made them aware of the implications of this for biology. He made them evolutionists; but ironically, he could not make them selectionists. It is sometimes said that Darwin converted the scientific world to evolution by showing them the process by which it had occurred. Yet the uneasy reservations about natural selection among Darwin's contemporaries and the widespread rejection of it from the 1890's to the 1930's suggest that this is too simplistic a view of the matter. It was more Darwin's insistence on totally natural explanations than on natural selection that won their adherence."
The triumph of Darwinian evolution rested on the prior triumph of positivism in the scientific community. Thus it was not the case that one scientific theory was judged more adequate than its scientific rivals; rather there was a change in the philosophy of science that no longer even recognized as scientific theories at all, what had been Darwin's rivals. Darwin, then, essentially won by default as the only scientific theory on the table. This way of doing science was, and is, not just a methodology, but rested on strong prior assumptions about reality.