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Cobb 1 Cody Cobb ENG 1304 Geoffrey Reiter 25 April 2006 Unintelligence Denied: Why ID Has No Place in a Science Classroom Charles Darwin and Alfred Russell Wallace’s theory of evolution via natural selection has been the best explanation for the origin of species for the past century and a half because it explains so much and is corroborated by many observations of natural phenomena. The processes of inheritable mutation and natural selection are the mechanisms which best explain the evidence for evolution. However, a new group of scientists and philosophers have, in recent years, sought to replace or at least supplement the theory of evolution via natural selection with a new theory, which they call intelligent design. Writing in Intelligent Design: The Bridge between Science and Theology, Dr. William Dembski states, “its fundamental claim is that intelligent causes are necessary to explain the complex, information-rich structures of biology and that these causes are empirically detectable” (Dembski 106). Supporters of intelligent design think their theory and criticisms of evolution – both of which are rejected by nearly all major institutions of scientists – warrant inclusion in public science classrooms. However, such changes would be misguided and potentially damaging to the students’ education, because intelligent design theory and the criticisms of evolution that are derived from it can be shown to be scientifically vacuous. On these grounds, no science curriculum should include the theory of intelligent design or unfounded critiques of current evolutionary theory. Cobb 2 For intelligent design to gain acceptance among the scientific community, and therefore be taught in science classrooms, the theory which it seeks to replace (evolution via natural selection) must first be shown to be seriously lacking in both explanatory power and evidence. Currently the theory lacks neither, which is why the overwhelmingly vast majority of life scientists continue to support it. Additionally, even if the theory was lacking significant explanatory power in one field of application, it may still be useful in other fields. For instance, Einstein’s theory of general relativity can explain everyday physical experience (as can Newtonian physics) in addition to large scale planetary and cosmological physics (which Newtonian physics cannot adequately explain). Yet, physics classes continue to use Newtonian physics today for everyday applications, because Newtonian physics adequately explains everyday physical phenomenon. Likewise, quantum mechanics best explains small-scale physical interactions – something that general relativity cannot accomplish. Yet all are still taught in science classes, because, while they may be incomplete theories, they still offer a wealth of explanatory power and are all observationally verified in their fields of application. Likewise, small-scale evolution (microevolution) explains the shifts in genetic frequencies of populations, while large-scale evolution (macroevolution) explains the emergence of differentiated organ structures and the inter-relatedness of all life. It should be noted that almost all proponents of intelligent design accept microevolution and only take issue with certain aspects of macroevolution. For the theory of intelligent design to gain mainstream scientific acceptance, it not only needs to offer greater explanatory power of natural phenomena than evolution, but it Cobb 3 must also be empirically testable. There must be a mechanism by which intelligent design functions that can be either directly or indirectly observed and be verified by all available evidence. For evolution that mechanism is the combination of inheritable mutation and natural selection (along with a handful of other processes, like genetic drift and gene flow), and it has been verified by discoveries in genetics, paleontology, ecology, anthropology, and geology. Currently, intelligent design offers no such mechanism that would explain the emergence of differentiated structures or the inter-relatedness of all life. In Darwin’s Black Box, Dr. Michael Behe illustrates a concept that he calls irreducible complexity, by which he means, “A single system composed of several wellmatched, interacting parts that contribute to the basic function, wherein the removal of any one of the parts causes the system to effectively cease functioning” (39). In what some consider a hurdle over which evolutionary explanations cannot jump, Behe places certain restraints on his concept: An irreducibly complex system cannot be produced directly (that is, by continuously improving the initial function, which continues to work by the same mechanism) by slight, successive modifications of a precursor system, because any precursor to an irreducibly complex that is missing a part is by definition nonfunctional. (39) Such a system could pose a serious problem to evolutionary thinking if, in fact, the evolution of certain systems relied only on direct, gradual changes that improved upon the same function. But evolution does not rely exclusively on such pathways, and Cobb 4 Behe is quick to point this out. However, he argues that the alternative indirect evolutionary routes to an irreducibly complex system are prohibitively implausible (40). Behe’s concept of irreducible complexity echoes the arguments of William Paley, which were advanced over a half a century before Darwin published Origin of Species. In Natural Theology, Paley formulated what is known as the teleological argument for the existence of God. He envisioned himself finding a watch on the ground and, noting the finely constructed details and obvious function the watch displayed, correctly inferred that such an intricately crafted object could not have arisen by blind, natural forces; instead, it must have been designed with purpose (Paley 3). For Paley the purpose evident in nature was made by the grace of God. For the modern intelligent design theory, that purpose can only be supplied by some sort of unspecified intelligent agent. Curiously, proponents of intelligent design insist that knowledge of the designer’s identity or nature is not necessary when inferring whether or not a system was designed by said designer. Moreover, intelligent design theory does not explain when or how a irreducibly complex system could have come into existence, whereas within the context of evolution there can be possible scenarios for the gradual change of a system into an irreducibly complex one. If there exists a system that can be appropriately identified as irreducibly complex, then the only way it could have arise via evolutionary processes would be an indirect, circuitous route – the kind Behe dismissed out of hand immediately after defining irreducible complexity. But such early dismissal is unfounded, since there are systems and structures that exhibit functions markedly different than their evolutionary forbearers. When Behe asserts that in irreducibly complex system would present a serious problem to evolution, he means to imply that the problem is too great to Cobb 5 overcome. In fact, the problem facing scientists is not, “How could we possibly believe in evolution in light of Behe’s concept of irreducibly complex structures,” but is rather, “How could evolution possibly explain the existence and origins of these structures?” In Why Intelligent Design Fails, Alan Gishlick gives a quick overview of the gradual evolution of the wing of a bird (Young 66-70). Such a structure is irreducibly complex in Behe’s original definition of the term, because if the wing lacked a single part it would not function and the bird would not be able to fly. However, the evolutionary pathway presented by Gishlick is indirect in the sense that the bird’s wing did not always function as a system designed for flight. For instance, one rather conspicuous property of a wing is the presence of feathers. Granted, an individual feather cannot be considered a “part” the way Behe uses the term (remove one feather and chances are the bird can still fly), but that only reflects Behe’s poor word choice when defining irreducible complexity, since feathers are obviously essential for bird flight. Using cladistic analysis and observing the available evidence from the fossil records, one can see that filamentous feathers existed as far back as 150 million years ago, such as those found on Sinosauropteryx. Early filamentous feathers were likely used for thermal regulation and not flight. Likewise, the bipedal nature of early theropods allowed for the forelimbs to be used for purposes other than walk, such as grasping. Several more developmental changes followed, each step beneficial to the organism, and eventually an irreducibly complex bird wing was formed. This is just one case where one or more structures began with their own respective functions and which additional developments followed that greatly modified the original functions of the original structures beyond recognition. Only later did Cobb 6 evolution select for feathers that were more aerodynamic or forelimbs with greater surface area. This co-option of structures that results in an overall different function of the system is what biologists and paleontologists call “exaptation” – a term that existed well before Behe’s book was ever published! Gishlick concludes his chapter by noting, “Irreducible complexity would be biologically significant if . . . it meant ‘unevolvable’” (Young 71). But irreducible complexity does not automatically equate to “unevolvability,” as the evolutionary history of the avian-flight system shows. Behe’s offhand dismissal of indirect routes as highly implausible can itself be dismissed in light of the evidence presented above. Behe, however, is a molecular biologist, and every irreducibly complex system he mentions is a molecular system composed of proteins and other cellular structures. His argument has become nothing more than stating, without any positive evidence, that one may legitimately infer design of an irreducibly complex molecular structure (e.g., the bacterium’s flagellum) in the absence of a detailed evolutionary history, since the probabilities of such structures occurring by chance are said to be greater than the number of atoms in the universe. Yet what does the answer “the designer did it” explain? The origin of a bacterium’s flagellum can at least be speculated about and various alternative pathways to the structures we observe today can be hypothesized within an evolutionary context. As a scientific theory, evolution via natural selection offers far more (if still incomplete) explanatory power for natural phenomena than intelligent design. There have been no serious proposals from proponents of intelligent design theory that suggest how the designer designed an irreducibly complex structure, when the designer designed an irreducibly complex structure, or even who or what the designer is. Evolution, Cobb 7 meanwhile, is fully capable of answering the how and when questions, and to a lesser extent the last question as well. In evolution’s case, as argued by Richard Dawkins in The Blind Watchmaker, the designer is actually the blind forces of known physical laws and natural selection (5). Dr. William Dembski states, “The world contains events, objects and structures that exhaust the explanatory resources of undirected natural causes and that can be adequately explained only by recourse to intelligent causes” (107). A skeptical reader who has just finished Dawkin’s Blind Watchmaker may think Dembski is advancing an argument from personal incredulity, which is another form of argument from ignorance (38), but Dembski reassures the reader in the following sentence, “This is not an argument from ignorance.” Dembski has developed what he calls an explanatory filter that can be used to detect and infer design. The explanatory filter, in effect, asks three questions about an event or object, “Is it contingent? Is it complex? Is it specified?” (Dembski 133). If something is contingent, then it can be explained by necessity, or natural law. The second possible cause of the event is due to chance, which could result in complex, if unspecified, structures. The third separate possible cause is one of design, which refers to complex events that are specified. All three possibilities are said to be “mutually exclusive and exhaustive” (Dembski qtd. in Perakh 23). Yet no justification is given for why all three possibilities should be mutually exclusive. Chance and law are arbitrarily separated by Dembski, neglecting the body of mathematics and physics devoted to statistical analysis of random events, the results of which are determined by certain statistical laws. A good demonstration of an essentially random event that is nevertheless Cobb 8 governed by law is the Gaussian distribution of a Galton board (Perakh 33). With this in mind, Dembski’s explanatory filter is in need of a serious reworking before it can actually be of any use to anyone. However, accepting for the moment that what Dembski said earlier is true, and that there are indeed events, objects, and structures that must be explained by intelligent causes, the obvious response to Dembski’s assertion is a demand for clarity. What kind of intelligence does he mean? Are we to assume that the intelligent causes are of supernatural origin? Dembski’s personal answer to the second question is yes, but he makes an interesting distinction between the location and actions of intelligent agents: Undirected natural causes can explain how ink gets applied to paper to form a random inkblot but cannot explain an arrangement of ink on paper that spells out a meaningful message. To obtain such a meaningful arrangement requires an intelligent cause. Whether an intelligent cause is located within or outside nature (i.e., is respectively natural or supernatural) is a separate question from whether an intelligent cause has acted within nature. Design has no prior commitment to supernaturalism. (259) So to Dembski, the possibility that intelligent causes may be supernatural in origin is ultimately irrelevant to the theory of design. Here Dembski is perched perilously on the fence of science and theology. But he also offers as an example in his passage a type of intelligence that can be detected in the natural world, namely the meaningful placement of letters on a piece of paper. Although Dembski purposefully leaves open the possibility that a supernatural intelligent agent could interfere with the natural world by Cobb 9 arranging objects and instilling within them some sort of informational meaning or significance, Dembski’s vague model of intelligence and information cannot be accurately applied to biological systems in the first place. Alphabetical letters represent an arbitrary set of symbols to which humans have attached specific meanings. A vertical line with a semicircle drawn from the opposite ends of the line and extending to right of it represents the letter known as “D.” One could conceivably, and without any change to the meaning of the words that would form, replace the letter D with another arbitrary symbolic representation. Since this keyboard is capable of displaying a limited number of characters, however, a pre-existing symbol must be chosen for sake of argument; in this case the character will be “#.” So if one were to rewrite “DOG” as “#OG,” the physical manifestation of the word would be different on paper, but the meaning would remain the same, since it was already decided arbitrarily in the beginning that D would equal #. However, in DNA, the fundamental instructions for all life, the function (meaning) of the different genetic “letters” (nucleotides) is tied intrinsically to the molecular structure of the “letters.” In the same way, the manner in which individual nucleotides join together to form a strand of DNA also dictates the function of the entire DNA strand. If one were to arbitrarily assign a chlorine atom in place of a hydroxyl group on a molecule of cytosine, a type of nucleotide, then the strand would not function properly. The crucial point missed by Dembski is that the molecular structures of DNA cannot rightly be considered “information” in the same sense as letters printed on paper, since molecules are subject to well understood natural laws, including physical and chemical interactions, in ways that printed letters are not. While not completely Cobb 10 understood, the sciences of self-organization and abiotic genesis are generating fascinating results and answering questions among a plethora of different, competing theories. The famous Urey-Miller experiment in the fifties demonstrated that organic molecules essential for the functions of life are able to form in an environment free of any detectable intelligent guidance or design. Without an appropriate application to biological systems, the intelligent design theory, as currently formulated, is again scientifically vacuous in this regard. Most disturbing about the intelligent design movement is its paucity of credible research publications about the theory. Even the most visible supporters of intelligent design agree that “without solid scholarship, research and argument, the project would be just another attempt to indoctrinate instead of persuade” (Wedge 14). In The Wedge Strategy, published by the Discovery Institute sometime in 1998, the goals for the intelligent design movement were made clear. When reassessing the strategy in 2003, the framers of the original document acknowledged that the “five-year plan . . . is now out of date. Many of its goals were reached or exceed, but some were not” (Wedge 12). Indeed, arguably the most important goal of the movement has failed to be realized: peerreviewed publication. Of the list of peer-reviewed academic papers that support intelligent design maintained by the Discovery Institute, very few are found in credible, impartial scientific journals, and even fewer actually offer original research. Most of the papers consist only of criticisms of evolution, and criticism of evolution cannot be automatically counted as support for intelligent design. One highly embarrassing inclusion on the list is Jonathan Wells’s paper in Rivista di Biologia. Rivista is no longer a credible scientific journal, as evidenced by its inclusion Cobb 11 of young earth creationist papers. Additionally, the actual content of Wells’s paper does not say much that is new: “Wells assumes that centrioles are designed to function as the tiny turbines they appear to be . . . He then formulates a testable hypothesis . . . that—if corroborated by experiment could have important implications . . .” (Peer-Reviewed 3) In other words, Wells simply assumes from the start a function for a cellular structure that is not well understood, claims without any evidence that such a structure would be irreducibly complex, and formulates a testable hypothesis that he has not bothered to test. This is hardly evidence for intelligent design. More credible, however, is Michael Behe and David Snoke’s paper that was published in Protein Science, a legitimately peer-reviewed science journal. Behe and Snoke tried to demonstrate that a particular type of evolutionary mechanism could not offer an adequate explanation for the appearance of new protein structures in a moderately sized population (2651). However, their paper does not rule out other evolutionary mechanisms, only the mechanism that is simplest to test; they say nothing at all in their paper that supports intelligent design; and their model has since been disputed in a later issue of the same journal (Lynch 2217). And finally, although not every scientist listed supports intelligent design theory, the Discovery Institute released a list of one hundred scientists who are skeptical of evolutionary explanations for the complexity of life. The list was designed to give the impression that there exists a legitimate scientific controversy and promote the idea that “careful examination of the evidence for Darwinian Theory should be encouraged” (Schaefer). To illustrate how ridiculous the Discovery Institute’s approach is, the National Center for Science Education began Project Steve. Compared to the Discovery Cobb 12 Institute’s list of one hundred scientists, the majority of whom are not biologists, Project Steve currently lists over 700 signatories who agreed to a statement that only evolution should be taught in science classrooms, while creationism and scientifically bankrupt theories such as intelligent design should not be taught. The only other difference between the Discovery Institute’s list and Project Steve is that signatories of Project Steve are restricted by one additional criterion: they must be named Steve, or some variant thereof. Steven Weinberg, a Nobel-winning scientist, explained the purpose of Project Steve in a press release from the National Center for Science Education: “science isn't decided by manifesto; this statement pokes fun at such efforts. If you want to know whether scientists accept evolution, you should look in the scientific literature” (Weinberg qtd. in Evans 1-2). In order for science classes to teach the theory of intelligent design there must be an actual theory to teach. Claiming to be able to infer design of biological systems on questionable mathematical probability sets and precious little else does nothing to advance human understanding of the natural world. Evolution, on the other hand, has proven to be well-established by all available evidence. For a classroom to abandon or denigrate such an elegant theory and replace it with another that has no apparent scientific basis is just not intelligent.