Charles Darwin called The Origin of Species “one long argument.” The whole point of it was to show that living things are not special creations, but modified descendants of common ancestors. Although The Origin of Species listed many facts from nature, Darwin’s argument was basically theological, and it took this general form: The facts of nature are “inexplicable on the theory of creation,” but make sense on the theory of descent with modification.
By “the theory of creation,” Darwin did not mean “creation within the past few thousand years.” Young-earth creationism was not the issue. The issue was whether a creator was necessary — after the origin of life itself — to explain the features we see in living things. But the creator Darwin envisioned was created by Darwin himself, and the alternative Darwin defended was materialistic philosophy. It’s no wonder that the controversy over Darwinism always involves theology and philosophy; they were there from the start.
Darwin frequently used his “inexplicable on the theory of creation” argument in connection with the geographic distribution of species. Asking “whether species have been created at one or more points on the earth’s surface,” he answered that “the view of each species having been produced in one area alone, and having subsequently migrated from the area as far as its powers of migration and subsistence under past and present conditions permitted, is the most probable.”1
In particular, “such cases as the presence of peculiar species of bats on oceanic islands and the absence of all other terrestrial mammals, are facts utterly inexplicable on the theory of independent acts of creation.” Based on his view about what God would have done, Darwin wrote: “He who admits the doctrine of the creation of each separate species, will have to admit that a sufficient number of the best adapted plants and animals were not created for oceanic islands; for man has stocked them far more fully than did nature.” So “why, it may be asked, has the supposed creative force produced bats and no other mammals on remote islands?” (This same theological argument is repeated in recent college textbooks on evolution.)2
According to Darwin, “On my view this question can easily be answered; for no terrestrial mammal can be transported across a wide space of sea, but bats can fly across.” But migration cannot account for all patterns of geographic distribution. Indeed, Darwin acknowledged in The Origin of Species that “the identity of many plants and animals, on mountain-summits, separated from each other by hundreds of miles of lowlands, where Alpine species could not possibly exist, is one of the most striking cases known of the same species living at distant points without the apparent possibility of their having migrated from one point to the other.” In such cases, Darwin argued that the recent ice age “affords a simple explanation of these facts.” Arctic plants and animals that were “nearly the same” could have flourished everywhere in Europe and North America, but “when the warmth had fully returned, the same species, which had lately lived together on the European and North American lowlands, would again be found in the arctic regions of the Old and New Worlds, and on many isolated mountain-summits far distant from each other.”3
So some cases of geographic distribution — the study of which modern biologists call “biogeography” — may be due to migration, while others may be due to the splitting of a formerly large, widespread population into small, isolated populations by changes in climate or geology — which modern biologists call “vicariance.”4
Darwin argued that all modern distributions of species could be explained by these two possibilities. Yet there are many cases of geographic distribution for which neither the center-of-origin-followed-by-migration nor the widespread-population-fragmented-by-barriers explanation seems to work.
One example is the worldwide distribution of flightless birds, or “ratites.” These include ostriches in Africa, rheas in South America, emus and cassowaries in Australia, and kiwis in New Zealand. Since the birds are flightless, explanations based on migration over vast oceanic distances are implausible. After continental drift was discovered in the twentieth century, it was thought that the various populations might have separated with the landmasses. But ostriches and kiwis are much too recent; the continents had already drifted apart when these species originated. So neither migration nor vicariance explain ratite biogeography, which remains controversial.5
Another example is freshwater crabs. Studied intensively by Italian biologist Giuseppe Colosi in the 1920s, these animals complete their life cycles exclusively in freshwater habitats and are incapable of surviving prolonged exposure to salt water. Today, very similar species are found in widely separated lakes and rivers in Central and South America, Africa, Madagascar, southern Europe, India, Asia and Australia. Fossil and molecular evidence indicates that these animals originated long after the continents separated, thereby contradicting the vicariance hypothesis. Some biologists speculate that the crabs may have migrated by “transoceanic rafting” in hollow logs, but this seems unlikely given their inability to tolerate salt water. So neither vicariance nor migration provides a convincing explanation for the biogeography of these animals.6
An alternative explanation was suggested in the mid-twentieth century by Léon Croizat, a French biologist raised in Italy. When Croizat studied the geographic distribution of many species he found that Darwin’s theory did “not seem to agree at all with certain important facts of nature.” Indeed, he concluded that “Darwinism is by now only a straitjacket… a thoroughly decrepit skin to hold new wine.” Croizat did not argue for independent acts of creation; instead, he proposed that in many cases a widespread primitive species was split into fragments, then its remnants evolved in parallel, in separate locations, into new species that were remarkably similar. Croizat called this process of parallel evolution “orthogenesis.” Neo-Darwinists such as Ernst Mayr, however, pointed out that there is no mechanism for orthogenesis, which implies — contrary to Darwinism — that evolution is guided in certain directions; so they rejected Croizat’s hypothesis.7
But if the only possibilities (as Darwin argued) were either independent acts of creation or Darwin’s hypotheses of migration and vicariance, the evidence amassed by Croizat would be more consistent with the former than the latter. Instead of providing sufficient evidence to support his view, Darwin simply dismissed creation on the grounds that it “is not a scientific explanation.”8 In effect, Darwin was attempting to settle the issue, not by evidence, but by definition: “Science” no longer meant testing Darwin’s theory of descent with modification by comparing it to the evidence; instead, it meant assuming that Darwin’s theory is true because it is the best materialistic explanation. Evidence became optional.
Darwin wrote in The Origin of Species that with few exceptions the “great facts in paleontology agree admirably with the theory of descent with modification through variation and selection.” Based on his theory, “we can understand… why the more ancient a form is, the more it generally differs from those now living,” and “why ancient and distinct forms often tend to fill up gaps between existing forms.” But such facts (he argued) “are wholly inexplicable on any other view” — such as the view that each layer of fossils marks “a new and complete act of creation.”9
Yet Darwin himself acknowledged that the fossil record posed problems for his theory. “By the theory of natural selection,” he wrote, “all living species have been connected with the parent-species of each genus, by differences not greater than we see between the natural and domestic varieties of the same species at the present day.” Thus in the past “the number of intermediate and transitional links, between all living and extinct species, must have been inconceivably great.” But Darwin knew that the major animal groups — which modern biologists call “phyla” — appeared fully formed in what were at the time the earliest known fossil-bearing rocks, deposited during a geological period known as the Cambrian. He considered this a “serious” difficulty for his theory, since “if the theory be true, it is indisputable that before the lowest Cambrian stratum was deposited long periods elapsed… and that during these vast periods the world swarmed with living creatures.” And “to the question why we do not find rich fossiliferous deposits belonging to these assumed earliest periods prior to the Cambrian system, I can give no satisfactory answer.” So “the case at present must remain inexplicable; and may be truly urged as a valid argument against the views here entertained.”10
Darwin defended his theory by citing the imperfection of the geological record. In particular, he argued that Precambrian fossils had been destroyed by heat, pressure, and erosion. Thus “we may perhaps believe that we see” in some areas of the world “the many formations long anterior to the Cambrian epoch in a completely metamorphosed and denuded condition.”11 Some of Darwin’s modern followers have likewise argued that Precambrian fossils existed but were later destroyed, or that Precambrian organisms were too small or too soft to have fossilized in the first place.
Since 1859, however, paleontologists have discovered many Precambrian fossils, many of them microscopic or soft-bodied. As American paleobiologist William Schopf wrote in 1994, “The long-held notion that Precambrian organisms must have been too small or too delicate to have been preserved in geological materials… [is] now recognized as incorrect.” If anything, the abrupt appearance of the major animal phyla in the Cambrian — which modern biologists call “the Cambrian explosion” — is better established now than in Darwin’s time. According to Berkeley paleontologist James Valentine and his colleagues, the “explosion is real, it is too big to be masked by flaws in the fossil record.” Indeed, as more fossils are discovered it becomes clear that the Cambrian explosion was “even more abrupt and extensive than previously envisioned.”12
It turns out that the problem with the fossil record is not that so many transitional forms are missing, but that fossils cannot provide evidence for descent with modification at all. Even in the case of extant species, buried remains cannot generally be used to establish ancestor-descendant relationships. Imagine finding two human skeletons in your back yard, one about thirty years older than the other. Was the older individual the parent of the younger? Without written genealogical records and identifying marks (or in some cases DNA), it is impossible to answer the question. And in this case we would be dealing with two skeletons from the same species that are only a generation apart. With fossils from different species that are now extinct, there is no way to establish that one is the ancestor of another — no matter how many transitional fossils we find.
In 1978, Gareth Nelson of the American Museum of Natural History wrote: “The idea that one can go to the fossil record and expect to empirically recover an ancestor-descendant sequence, be it of species, genera, families, or whatever, has been, and continues to be, a pernicious illusion.”13 Nature science writer Henry Gee doesn’t doubt Darwinian evolution, but he candidly admits that we cannot infer it from fossils. “No fossil is buried with its birth certificate,” he wrote in 1999. We call new fossil discoveries missing links “as if the chain of ancestry and descent were a real object for our contemplation, and not what it really is: a completely human invention created after the fact, shaped to accord with human prejudices.” Gee concluded: “To take a line of fossils and claim that they represent a lineage is not a scientific hypothesis that can be tested, but an assertion that carries the same validity as a bedtime story — amusing, perhaps even instructive, but not scientific.”14
So what does the fossil record really show us? It shows that the earth was once populated by now-extinct creatures, and that the history of life has passed through several stages. But the fossil record lacks the innumerable transitional links demanded by Darwin’s theory, and even the few intermediate forms it contains cannot establish ancestor-descendant relationships. If the only two possibilities (as Darwin argued) were either independent acts of creation or gradual descent with modification, then many features of the fossil record (like much of the evidence from biogeography) would be more consistent with the former than the latter.
Darwin argued in The Origin of Species that the widespread existence of vestigial organs — organs that may have once had a function but are now useless — is evidence against creation. “On the view of each organism with all its separate parts having been specially created, how utterly inexplicable is it that organs bearing the plain stamp of inutility… should so frequently occur.” But such organs, he argued, are readily explained by his theory: “On the view of descent with modification, we may conclude that the existence of organs in a rudimentary, imperfect, and useless condition, or quite aborted, far from presenting a strange difficulty, as they assuredly do on the old doctrine of creation, might even have been anticipated in accordance with the views here explained.”15
In The Descent of Man, Darwin cited the human appendix as an example — but the appendix is not a vestigial organ. Once thought to be functionless, it is now known to be an important source of antibody-producing blood cells and thus an integral part of the human immune system. It may also serve as a compartment for beneficial bacteria that are needed for normal digestion. So the appendix is not useless at all.16
In 1981, Canadian biologist Steven Scadding argued that although he had no objection to Darwinism, “vestigial organs provide no evidence for evolutionary theory.” The primarily reason is that “it is difficult, if not impossible, to unambiguously identify organs totally lacking in function.” Scadding cited the human appendix as an organ previously thought to be vestigial but now known to have a function. Another Canadian biologist, Bruce Naylor, countered that an organ with some function can still be considered vestigial. Naylor also argued that “perfectly designed organisms necessitated the existence of a creator,” but “organisms are often something less than perfectly designed” and thus better explained by evolution. Scadding replied: “The entire argument of Darwin and others regarding vestigial organs hinges on their uselessness and inutility.” Organs with functions may be homologous (see below), and Darwin argued that homologous organs provided evidence for his theory, but Naylor’s redefinition led him (according to Scadding) “to mix up the vestigial organ argument with the homologous organ argument. Darwin treated these arguments separately recognizing that they were in fact independent.” Scadding also objected that Naylor’s “less than perfectly designed” argument was “based on a theological assumption about the nature of God, i.e. that he would not create useless structures. Whatever the validity of this theological claim, it certainly cannot be defended as a scientific statement, and thus should be given no place in a scientific discussion of evolution.”17
Despite Scadding’s critique, modern Darwinists not only continue to argue that vestigial organs are evidence for descent with modification, but they also continue to base their argument on theological reasoning similar to Darwin’s. For example, Douglas J. Futuyma’s 2005 college biology textbook states: “According to creationist thought, an intelligent creator must have had a purpose, or design, in each element of his creation. Thus all features of organisms must be functional. For this reason, creationists view adaptations as support for their position. However, nonfunctional, imperfect, and even maladaptive structures are expected if evolution is true.” Thus “Darwin and subsequent evolutionary biologists have described innumerable examples of biological phenomena that are hard to reconcile with beneficent intelligent design… If ‘good design’ were evidence of a kindly, omnipotent designer, would ‘inferior design’ be evidence of an unkind, incompetent, or handicapped designer? Only evolutionary history can explain vestigial organs.”18
But the “vestigial organs” argument for Darwinism is a house built on sand. The more we learn about living things, the more we discover that features previously thought to be functionless actually have functions. The human appendix is just one example. So the claim that vestigial organs provide evidence for Darwinism is basically a “Darwin of the gaps” argument19 that collapses under the weight of new evidence and reduces to the argument from homology.
Biologists since Aristotle have noticed that very different organisms share some remarkable similarities. One kind of similarity is functional: Butterflies have wings for flying, and so do bats, but the wings of the two animals are constructed very differently. Another kind of similarity is structural: The pattern of bones in a bat’s wing is similar to that in a porpoise’s flipper, though the wing is used for flying and the flipper is used for swimming.
In the early nineteenth century, the first kind of similarity was called “analogy.” The second kind was called “homology” and defined as “similarity of structure and position.” Analogy suggests independent adaptations to external conditions or needs, while homology suggests deeper structural affinities that could serve as a guide to classifying organisms into species, genera, families, and so on.
In The Origin of Species, Darwin used a theological argument similar to the one he used with geographic distribution, fossils and vestigial organs to explain why homologies provided support for his theory. “How inexplicable,” he wrote, are “homologies on the ordinary view of creation.” For example: “Why should similar bones have been created to form the wing and leg of the bat, used as they are for such totally different purposes?” On the other hand, “the similar framework of bones in the hand of a man, wing of a bat, fin of the porpoise, and leg of the horse… at once explain themselves on the theory of descent with slow and slight modifications.”20
The normal approach of empirical science, however, would not be to argue against a theological view, but to propose a testable mechanism to explain how different species acquire homologous features. The mechanism proposed by modern Neo-Darwinism is the inheritance of similar genes from a common ancestor. Genes carry information from one generation to the next, and according to Neo-Darwinian theory they direct the development of the embryo. If it could be shown that homologous structures are produced by similar (but not different) genes, and that non-homologous structures are produced by different (but not similar) genes, we would have scientific evidence that homology is due to common ancestry.
This is not the case, however, and biologists have known it for decades. Some homologous structures — such as the body segments in fruit flies and locusts — depend on different genes. And many non-homologous structures — such as the eyes of octopuses and humans, or the legs of mammals and insects — depend on similar genes. In 1971, Gavin de Beer wrote: “It might be thought that genetics would provide the key to the problem of homology. This is where the worst shock of all is encountered,” because “characters controlled by identical genes are not necessarily homologous… [and] homologous structures need not be controlled by identical genes.” De Beer concluded that “the inheritance of homologous structures from a common ancestor… cannot be ascribed to identity of genes.”21
So the testable mechanism proposed by Neo-Darwinists has been empirically disproved, and Darwin’s followers — like Darwin himself — fall back on theological arguments. In 1983, Stephen Jay Gould: “Perfection could be imposed by a wise creator or evolved by natural selection… Evolution lies exposed in the imperfections that record a history of descent. Why should a rat run, a bat fly, a porpoise swim, and I type this essay with structures built of the same bones unless we all inherited them from a common ancestor? An engineer, starting from scratch, could design better limbs in each case.” Gould’s statement is just one example of what philosopher of biology Paul A. Nelson called in 1996 “a remarkable but little studied aspect of current evolutionary theory” — namely, “the use by many biologists and philosophers of theological arguments for evolution.”22
Darwin’s Straw God
Historian Neal C. Gillespie noted in 1979 that “Darwin’s theological defense of descent with modification” rested on his conception of the creator, and that The Origin of Species “not only has numerous references to such a creator, but theological arguments based on such a conception had some importance in its overall logic.” In fact, The Origin of Species was “significantly dependent on theology” for its claims. In 1982, historian of science Barry G. Gale wrote in a book titled Evolution Without Evidence that “given the relative paucity of evidence then available to Darwin,” he was forced to rely heavily on the argument that his theory was better than the doctrine of special creation — and this was “the strongest line of arguments” in The Origin of Species.23
According to biophysicist Cornelius G. Hunter, the essence of Darwin’s “one long argument” was that “evolution is true because divine creation is false.” Darwin started with an idea of “how God would go about creating the world” and found that it did not match the facts of nature, “but the mismatch depends every bit as much on the theology as on the science.”24
Darwin argued against the existence of a god who would have created species with the characteristics that make it possible to classify them hierarchically into species, genera, and other categories. Such a god would not have created extant species that are geographically distributed the way they are, nor would he have created extinct species that appear in the progressive pattern we see in the fossil record. Such a god would not have created species with vestigial organs, nor would he have created species in which similar structures perform different functions. Instead, the god against whom Darwin argued would have engaged in “independent acts of creation” that were arbitrary and unconnected, producing no discernible patterns such as we find in the fossil record or in living organisms.
Some of Darwin’s modern followers argue similarly. In Finding Darwin’s God (1999), Kenneth R. Miller asked why the creator would have “produced one organism after another in places and in sequences that would later be misinterpreted as evolution by one of his creatures. And just to compound that misinterpretation, he would ensure that the very first limbs he designed looked just like modified limbs.” Such things “clearly give the appearance of evolution.”25
But the answer to Miller’s (and Darwin’s) challenge has long been a part of the Christian tradition. In the fourth century after Christ, Basil of Caesarea and Gregory of Nyssa both argued that the sequential character of creation was God’s way of preparing the way for human beings, who were His goal from the beginning.26 In a 1976 book aptly titled Forgotten Truth, Huston Smith wrote: “Earth mirrors heaven. But mirrors, as we have noted, invert. The consequence here is that that which is first in the ontological order appears last in the temporal order.” Smith explained: “In the celestial realm the species are never absent; their essential forms or archetypes reside there from an endless beginning. As earth ripens to receive them, each in its turn drops to the terrestrial plane.” But “first a viable habitat must be devised, hence the inorganic universe is matured to a point where life can be sustained. And when living beings do arrive, they do so in a vaguely ascending order that passes from relatively undifferentiated organisms… to ones that are more complex.” Thus “man, who is first in the order of worth on the terrestrial plane, will be last in the order of his appearance.”27
So the theological target of Darwin’s “one long argument” was not the God of traditional Christianity, but a caricature. Darwin fabricated a “god” who did not exist, a deity who engaged only in arbitrary and unrelated acts of creation, then he argued against this fictional god. Rhetoricians call this a “straw man argument” — though in this case “straw god argument” would be more appropriate.28
In place of this straw god, Darwin claimed to prefer one who created a few original forms and then let the laws of variation and selection govern their evolution. He wrote in The Origin of Species: “It is just as noble a conception of the Deity to believe that He created a few original forms capable of self-development into other and needful forms, as to believe that He required a fresh act of creation to supply the voids caused by the action of His laws.”29
But Darwin never defended the existence of such a god. Indeed, it is questionable whether he was even sincere in suggesting it. After the first edition of The Origin of Species, he added to the last paragraph the concession that life was “originally breathed by the Creator into a few forms or into one.” But he later regretted this, writing in an 1863 letter: “I have long regretted that I truckled to public opinion, and used the Pentateuchal term of creation, by which I really meant ‘appeared’ by some wholly unknown process.”30
So Darwin’s “one long argument” was not an argument for a god of any kind. It was an argument against a role for God in the history of life — at least, after the origin of life itself. Darwin wrote in 1859: “I would give absolutely nothing for the theory of natural selection, if it requires miraculous additions at any one stage of descent.”31
The Origin of Species was also an argument for a completely natural mechanism — natural selection acting on small variations. Like the arguments for descent with modification we examined above, however, Darwin’s arguments for the mechanism of evolution were not based on evidence.
Empirical Science or Materialistic Philosophy?
Empirical science tests hypotheses by comparing them with the evidence. Even if a hypothesis is supported by evidence, scientists hold it tentatively, since further evidence might prove it wrong. In contrast, philosophy deduces conclusions from assumptions. If philosophers accept the assumptions and obey the rules of logic, their conclusions follow necessarily, with or without evidence from nature.
The cornerstone of Darwin’s theory was natural selection, but he had no actual evidence for it. There was plenty of evidence from domestic breeding that artificial selection could modify existing species of plants and animals, but when it came to natural selection the best Darwin could do in The Origin of Species was “give one or two imaginary illustrations.” This did not stop him from speculating: “As man can produce, and certainly has produced, a great result by his methodical and unconscious means of selection, what may natural selection not effect?” Indeed, he believed that “the most exalted object which we are capable of conceiving, namely, the production of the higher animals, directly follows.” But Darwin did not have the evidence to justify this sweeping claim, still less his conclusion that natural selection will “banish the belief of the continued creation of new organic beings.”32
A century after Darwin, biologists began finding evidence for natural selection, and there is now no doubt that natural selection occurs. But the evidence consistently shows that natural selection is no more powerful than artificial selection — in other words, it produces only minor changes within existing species.
The second major element in Darwin’s proposed mechanism was variation — the minor differences we see among the individuals in any population of living things. “Natural selection can do nothing,” Darwin wrote, without “the occurrence of profitable variations.” But Darwin did not know the origin of variations.33
In 1866, Augustinian monk Gregor Mendel determined experimentally that several features of pea plants are due to discrete factors that are inherited according to a few simple rules. (The factors were later named “genes” by Danish botanist Wilhelm Johannsen.) But Mendel found Darwin’s theory unpersuasive, and Darwinists ignored his ideas for half a century. By the 1930s, the evidence for Mendel’s ideas had grown, and Darwin’s followers embraced them in order to explain variation. According to the resulting synthesis of Darwinian evolution and Mendelian genetics — Neo-Darwinism — variations are due to differences in genes, and new variations are the result of genetic mutations.34
But the vast majority of genetic mutations, if they have any effect at all, are harmful, and according to Darwin “any variation in the least degree injurious would be rigidly destroyed” and thus make no contribution to evolution.35 A few mutations are beneficial in certain environments, but they affect only single molecules — they do not confer new anatomical characteristics or produce new species. Neo-Darwinism needs mutations that can lead to new species, organs and body plans, and such mutations have never been observed. All of the evidence points to one conclusion: No matter what we do to the DNA of a mouse embryo, there are only three possible outcomes: a normal mouse, a defective mouse, or a dead mouse.36
In 1937, Neo-Darwinist Theodosius Dobzhansky noted that there was no hard evidence to connect small-scale changes within existing species (“microevolution”) to the origin of new species or the large-scale changes we see in the fossil record (“macroevolution”). But since “there is no way toward an understanding of the mechanisms of macroevolutionary changes, which require time on a geological scale, other than through a full comprehension of the microevolutionary processes observable within the span of a human lifetime,” Dobzhansky concluded: “For this reason we are compelled at the present level of knowledge reluctantly to put a sign of equality between the mechanisms of macro- and microevolution, and proceeding on this assumption, to push our investigations as far ahead as this working hypothesis will permit.”37
Yet microevolution is simply a post-Darwinian label for changes within existing species — something people had been studying for centuries before Darwin. Animal breeding and horticulture were well developed before 1800. Pre-Darwinian breeders knew the importance of selection, and many books about it were available in English by 1859. If Darwin had written a book titled How Existing Species Change Over Time, it probably would have attracted little attention — especially since he had no evidence for natural selection and didn’t know the origin of variations. Indeed, modern advances in our understanding of microevolution owe far less to Darwin’s theory than to Mendel’s work in genetics.38
The first step in macroevolution would be the origin of a new species — what Darwin called “the mystery of mysteries” and modern biologists call “speciation.” Yet the “mystery of mysteries” is still unsolved. In 1997, evolutionary biologist Keith Stewart Thomson wrote: “A matter of unfinished business for biologists is the identification of evolution’s smoking gun,” and “the smoking gun of evolution is speciation.” Before Darwin, centuries of artificial selection had seemingly demonstrated that species can vary only within certain limits. “Darwin had to show that the limits could be broken,” wrote Thomson, “so do we.”39
The best way to find “evolution’s smoking gun” would be to observe speciation in action. There actually are some confirmed cases of observed speciation in plants — all of them due to an increase in the number of chromosomes, or “polyploidy.” But observed cases of speciation by polyploidy are limited to flowering plants, and polyploidy does not produce the major changes required for Darwinian evolution. Darwinism depends on the splitting of one species into two, which then diverge and split and diverge and split, over and over again, to produce the branching-tree pattern required by Darwin’s theory. And this sort of speciation has never been observed.40
In 2001, British bacteriologist Alan H. Linton wrote that he had gone looking for direct evidence of speciation. He concluded: “None exists in the literature claiming that one species has been shown to evolve into another. Bacteria, the simplest form of independent life, are ideal for this kind of study, with generation times of twenty to thirty minutes, and populations achieved after eighteen hours. But throughout 150 years of the science of bacteriology, there is no evidence that one species of bacteria has changed into another… Since there is no evidence for species changes between the simplest forms of unicellular life, it is not surprising that there is no evidence for evolution from prokaryotic [e.g., bacteria] to eukaryotic [e.g., plant and animal] cells, let alone throughout the whole array of higher multicellular organisms.”41
So although Darwinists believe that all species have descended from a common ancestor through variation and selection, they cannot point to a single observed instance in which even one species has originated in this way. Evolution’s smoking gun is still missing, and Dobzhansky’s working assumption that macroevolution equals microevolution remains nothing more than an assumption.
According to Neal Gillespie, “it is sometimes said that Darwin converted the scientific world to evolution by showing them the process by which it had occurred,” but “it was more Darwin’s insistence on totally natural explanations than on natural selection that won their adherence.” The Darwinian revolution was largely philosophical, and Darwin’s philosophy limited science to “the discovery of laws which reflected the operation of purely natural or ‘secondary’ causes.” Furthermore, “there could be no out-of-bounds signs… When sufficient natural or physical causes were not known they must nonetheless be assumed to exist to the exclusion of other causes.”42
So Darwinism not only limits science to the search for natural explanations, but it also insists that such explanations must exist even when they cannot be found. Some people would argue that Darwin was right to limit science to the search for natural explanations. From their perspective, a scientific hypothesis must be testable, and hypotheses about the supernatural cannot be tested. This is sometimes called “methodological naturalism,” to distinguish it from “metaphysical naturalism.” The former implies a limit to what science can investigate; there may be aspects of the world that are beyond its reach. The latter, by contrast, is a statement about the whole of reality; it is just another term for philosophical materialism.
But what does the insistence on methodological naturalism actually mean for science? According to Christian philosopher Alvin Plantinga: “If you exclude the supernatural from science, then if the world or some phenomena within it are supernaturally caused — as most of the world’s people believe — you won’t be able to reach that truth scientifically. Observing methodological naturalism thus hamstrings science by precluding science from reaching what would be an enormously important truth about the world. It might be that, just as a result of this constraint, even the best science in the long run will wind up with false conclusions.”43
Defenders of methodological naturalism claim that there cannot possibly be evidence for supernatural causes. But the biblical writers claimed otherwise. Who is right? What if a modern scientist were to find evidence that seems to point to a supernatural cause? Methodological naturalism would block the inference and require a never-ending search for natural causes. Under the circumstances, science would be prevented from following the evidence wherever it leads. According to philosopher Del Ratzsch, “If one restricts science to the natural, and assumes that science can in principle get to all truth, then one has implicitly assumed philosophical naturalism.” Thus “methodological naturalism is not quite the lamb it is sometimes pictured as being.”44
Methodological naturalism may also induce people to cling to ideas that are unsupported — or actually contradicted — by the evidence. If a person refuses to question Darwinism simply because it is the best naturalistic explanation available, even though the evidence is inconsistent with it, then that person is no longer engaged in the activity most people think of as science — namely, determining whether hypotheses fit the evidence. As Phillip E. Johnson has pointed out, “Naturalism and empiricism are often erroneously assumed to be very nearly the same thing, but they are not. In case of Darwinism, these two foundational principles of science are in conflict.”45
Darwinist Richard C. Lewontin wrote in 1997: “We take the side of science in spite of the patent absurdity of some of its constructs, in spite of its failure to fulfill many of its extravagant promises of health and life, in spite of the tolerance of the scientific community for unsubstantiated just-so stories, because we have a prior commitment, a commitment to materialism. It is not that the methods and institutions of science somehow compel us to accept a material explanation of the phenomenal world, but, on the contrary, that we are forced by our a priori adherence to material causes to create an apparatus of investigation and a set of concepts that produce material explanations, no matter how counter-intuitive, no matter how mystifying to the uninitiated. Moreover, that materialism is absolute, for we cannot allow a divine foot in the door.”46
So Darwinism starts by assuming materialism. Only from that perspective does the fragmentary and inconsistent evidence from nature seem to support the theory — and then only because no other perspectives are permitted. In 1986, Darwinist Richard Dawkins wrote that “Darwin made it possible to be an intellectually fulfilled atheist.”47 It is no wonder that Dawkins and many other followers of Darwin find support for atheism in his theory; it was there from the start.
The Ancient Philosophical Roots of Darwinism
Six centuries before the Christian era (B.C.E.), the Greek philosopher Anaximander asserted that the first living things emerged from formless matter and then underwent transmutations to produce a wide variety of forms. In what some commentators regard as a primitive form of evolutionary theory, Anaximander apparently held that humans descended from some other species of animal — probably a fish.48 In the fifth century B.C.E., the Greek philosopher Empedocles taught that the chance interplay of earth, air, fire and water produced disconnected organs and limbs that wandered aimlessly about until they combined spontaneously to make whole creatures. Most of the resulting combinations were monstrosities — with faces and breasts on the back as well as front, or half ox and half human — that were so maladapted that they perished. Among the few that survived were creatures that eventually developed into modern humans.49
Leucippus and Democritus in the fifth century B.C.E. and Epicurus in the fourth century B.C.E. advocated a materialistic philosophy in which no gods exist — only atoms and the void.50 In the first century B.C.E., the Roman philosopher Lucretius immortalized this view in his long poem “On the Nature of Things.” Book Five begins with an attack on religion and teleology, then it lays out a theory of survival of the fittest that is remarkably similar to Darwin’s. Although Lucretius did not suggest that all living things are descended from a common ancestor, he believed that all things — including living organisms and human beings — are products of aimless interactions among atoms. If they are well adapted to their environment, they survive and leave descendants; if not, they perish.51
Some modern followers of Charles Darwin regard these ancient thinkers as their intellectual forebears. According to a 1996 statement on a pro-evolution web site maintained by the University of California at Berkeley, “evolutionary theory begins” with Anaximander. Although his ideas “drew on the religious and mythical ideas of his time, he was still one of the first to attempt an explanation of the origin and evolution of the cosmos based on natural laws.” Thus Anaximander’s theory “bears some resemblance to evolutionary theory.” According to the same web site Empedocles proposed a theory that “seems a bit bizarre today” but was nevertheless “a sort of evolutionary theory: Past natural selection is responsible for the forms we see today. Empedocles also ascribed the origin of the life of today to the interplay of impersonal forces, in which chance, not the gods, played the major role.” Thus the Greeks “led the way in developing a general scientific worldview — one in which natural, non-miraculous explanations for the causes of phenomena were sought.”52
Of course, there were differences between the ideas of the ancient Greeks and modern evolutionary theory, but they were similar in one fundamental respect: They attributed cosmic and biological origins to unguided natural processes rather than divine design. As modern evolutionary biologist Ernst Mayr put it, the ancient Greek theories “constitute the first scientific revolution, so to speak, a rejection of supernatural in favor of materialistic explanations.”53
For Mayr and the author of the Berkeley evolution web site, and for other followers of Charles Darwin, “science” is synonymous with “materialistic explanation.” In this respect, they are following in the footsteps of ancient materialistic philosophers.
This is why modern controversies over evolution are not really about empirical science. Although many of Darwin’s followers believe that he presented overwhelming evidence for his theory, nothing could be further from the truth. The Origin of Species is just warmed-over materialistic philosophy, decorated with illustrations borrowed from nineteenth-century science.
1Darwin, Charles. The Origin of Species. Sixth Edition. London: John Murray, 1872. Available online (2008) here.
Quotations here are from Chapter XII (pp. 281-284). Page numbers in this and following notes refer to the Modern Library Edition.
2Darwin, The Origin of Species, Chapters XIII (pp. 304-308) and XV (p. 365).
Darwin relied on theological arguments throughout The Origin of Species. See Chapter II (p. 50), Chapter IV (p. 99), Chapter V (pp. 105, 113, 115, 117, 122), Chapter VI (pp. 132, 141, 143-144, 147, 150), Chapter VIII (p. 208), IX (p. 231), Chapter XI (pp. 257-258), Chapter XII (pp. 281, 282, 283, 290, 293), Chapter XIII (pp. 304, 305, 307, 308, 310, 314), Chapter XIV (pp. 323, 334, 335-336, 350), and Chapter XV (pp. 360, 361, 362, 363, 365, 366, 367-368, 369, 373). There is so much theology in The Origin of Species that if it is allowed in U. S. public school science classes (as it should be) there are no reasonable grounds to exclude other books on the subject that also include theology.
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I thank Michael Pickard for suggesting the term “straw god” to me.
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