In the ongoing and complex issue of teaching evolution in public schools, "intelligent design" (ID) purports to overcome objections to inserting religion into science classrooms and to illustrate conceptual and empirical shortcomings in evolutionary theory. ID supporters argue that students should be made aware of these shortcomings and suggest that "alternatives to evolution" need to be taught. A key issue that needs to be resolved is whether it is a sound pedagogical approach to teach "design" alongside evolution, which may in part be resolved by helping policy makers determine whether ID is a true rival to evolutionary theory — or has any scientific merit at all.
Even though creationism, in its various forms, has typically failed to pass legal muster, the Supreme Court has not categorically forbidden biology teachers from discussing "alternatives to evolution" as long as those lessons do not cause religion and science to be overly intertwined. ID supporters and other critics of evolution typically latch on to the Edwards v Aguillard ruling to provide legal grounds for introducing challenges to evolution in the classroom. According to the Edwards Court, "teaching a variety of scientific theories about the origins of humankind to schoolchildren might be validly done with the clear secular intent of enhancing the effectiveness of science instruction" (Edwards v Aguillard 482 US 578 [1987]: 594). In accordance with their interpretation of this case and other legal precedents, ID supporters seek to take advantage of a "legal opening" to offer what they argue is a secular, scientific body of claims.
Although the teaching of ID has not been specifically required in accordance with most states' science standards, several state school boards and legislatures have considered implementing proposals that would encourage teachers to discuss evidence against evolution (Carroll 2005; Taylor and MacDonald 2002). In Ohio, the state school board explicitly considered incorporating it into the curriculum (Stephens 2004). Missouri's legislature has considered a bill that would require teachers to discuss alternatives to evolution (Anonymous 2004). The school board in Dover, Pennsylvania, became the first one to mandate that ID be taught as part of the biology curriculum (Raffaele 2004). Yet a federal judge has since invalidated Dover's policy. At this point, the Discovery Institute, one of the main organizations defending the notion that ID is a credible scientific theory, is not openly advocating that it should be a mandatory part of biology education (Meyer 2002), opting instead for tactics that try to cast doubt on the validity of evolution.
"TEACH THE CONTROVERSY"
One of the main arguments in support of teaching ID in public schools is that students need to be aware of the controversy circulating around evolution. If portions of evolutionary theory are truly on shaky ground, then ID supporters suggest that students need to be made aware of this fact. This is the so-called "teach the controversy"approach. Since ID supporters argue that there is substantial evidence contradicting at least some of the claims supporting evolution, students should be apprised of the situation and then make up their own minds on what is true. Further, even if there is evidence to support evolution, students need to be cautioned against merely assuming that it is "fact" just because it is presented in a classroom. According to ID supporters, there is momentum behind the "teach the controversy" approach as evidenced by a document that contains signatures from scientists who believe there are flaws contained within Darwinism (Discovery Institute 2001). Yet the "teach the controversy" approach, as articulated by Stephen Meyer (Meyer 2002), is profoundly misguided.
To begin, Meyer contends, "When two groups of expert disagree about a controversial subject that intersects the public school curriculum students should learn about both perspectives" (Meyer 2002). According to Meyer:
In such cases teachers should not teach as true only one competing view, just the Republican or Democratic view of the New Deal in a history class, for example. Instead, teachers should describe competing views to students and explain the arguments for and against these views as made by their chief proponents.
Yet it is not possible to present students with each and every dispute that is ongoing within the expert communities, let alone every dispute that is ongoing between scientists. It would be arduous and impractical to cover, as Meyer's logic implies, each particular political party's arguments, such as the ones offered by libertarians, socialists, the Green Party, and the Reform Party, on each controversial political issue. In other words, there are numerous other options beyond "both perspectives"offered by Democrats and Republicans that could be mentioned with reference to the issue. Further, we would certainly want to disregard the opinions of some groups, such as white supremacists and neo-Nazis, even if they do offer a "competing view" on politics. Not every "competing view" warrants consideration even though some might consider them to be rivals.
ID supporters defend the notion that students need to be made aware of "the controversy" in part because they see ID as being among the main candidates to be covered alongside evolution. Yet the logic of Meyer's argument opens the door to discussing various alternative views on the history of life, such as the one offered by the Raëlians that human life emerged on this planet through cloning procedures undertaken by human-like aliens. The Raëlian view is undoubtedly a "rival" (in some sense of the term) to evolution since it attempts to explain how human life on this planet emerged; it does challenge a number of evolution's tenets. Raëlians proclaim that they can offer a competing explanation for how life began and that their view merits serious consideration. As a result, the "teach the controversy" approach implies that such a view would not be discounted as a candidate to be discussed in biology classrooms, which is a profoundly troubling consequence.
Introducing students to each and every rival view as it emerges, such as the one offered by the Raëlians, can give them the wrong impression that each expert's or group's opinion is of equal worth and has the same level of supporting evidence behind it. In accordance with the goal of teaching students about controversies, teachers could plan lessons on witchcraft, astrology, and tealeaf reading, as Paul Feyerabend suggests (Feyerabend 1975), because there are inquirers who use these approaches in order to acquire evidence. Yet there are good compelling reasons to resist this type of thinking, which in part relates to the value and importance of obtaining evidence to support claims before students learn about them. There are plenty of individuals who purport to be "scientific" experts, but the mechanisms of science need time to evaluate and assess the relevant theories in question. It can be unwise to present an expert's arguments until relevant claims have been thoroughly examined by other experts. The implication that rival views are all on even grounds scientifically (have the same level of supporting evidence) does a disservice to how science works.
Thomas Murray describes a similar phenomenon within the context of debates over embryonic stem cell research (Murray 2001). As Murray points out, the manner in which disputes about science are typically presented to the public and to policy makers — by inviting one or two scientists on opposite sides of the spectrum to speak — implies that scientists are evenly divided on an issue. This approach can grossly distort how much consensus there actually is within the scientific community about an issue such as stem cell research. Similarly, if the views of a biologist and an ID supporter are presented at the same forum, it could mislead the audience to think that the scientists themselves are split, for example, on the issue of whether evolution is accepted as fact. Applying this insight to the classroom, presenting "both perspectives" to students implies that each one is on equal footing and that scientists are evenly divided into the two camps. Recognizing this implication does not necessarily prove that ID is false, but the biology curriculum needs to reflect accurately its standing within the scientific community.
DISPUTING EVOLUTION
Meyer and other ID supporters contend that there is active scientific "controversy" about whether evolution's key tenets are supported by evidence. Yet labeling it as a "controversy" about evolution is misleading because the disputes are not primarily within the scientific community. The controversy occurs among religious groups, politicians, parents, and advocacy groups. Disputes about whether evolution is a "fact" frequently are waged at school board meetings and at legislative sessions by these groups, but not among scientists in relevant disciplines.
There are of course active disputes within scientific communities regarding the specific mechanisms governing evolution, including the issue of how significant the role of natural selection is. There have also been debates about the tempo of evolutionary change (for example, Eldredge and Gould 1972) and the unit of selection (Sachs and others 2004). Although biologists ardently disagree on some of the details of how evolution works, they are largely convinced that it did in fact occur. According to the National Science Teachers Association, "There is no longer a debate among scientists about whether evolution has taken place"(NSTA 2003). Thus, couching the issue as a "scientific" controversy between the scientists themselves misrepresents how divided the scientific community actual is on the issue. For example, according to Chad Edgington (Edgington 2004):
...given the diversity of belief on the subject and the lack of accepted, substantiated evidence supporting any theory, whether one is a creationist or an evolutionist is largely a matter of opinion.
Vocal proponents of "intelligent design", such as Michael Behe and William Dembski, offer passionate defenses of their views, but they are noticeably on the outside of the scientific community. Neither creationism nor "intelligent design" is considered to be a viable alternative to evolution by most scientists. Scientists vehemently and consistently challenge the notion that evolution still needs to overcome the burden of proof to vanquish either "rival" theory.
THE PUBLIC FAVORS IT
The "teach the controversy" approach also takes advantage of the notion that the public seems comfortable with teaching "alternatives to evolution" along with the theory. There is some basis for Meyer's statement that "voters overwhelmingly favor this approach" (Meyer 2002). For example, according to one Gallup poll, 68% of Americans favor teaching both creationism and evolution in biology classrooms (Moore 1999). A Zogby poll suggests that 71% of Americans would prefer that evidence both for and against evolutionary theory be taught (Zogby International 2001). However, even though Meyer's assertion about public opinion may be accurate, it is not necessarily sound educational policy to allow the public to dictate what is taught within a discipline, especially in the sciences where extensive knowledge of technical concepts and background information is typically needed before claims can be properly assessed.
Along these lines, there is evidence to indicate that the public's understanding of science may be inadequate (National Science Board 1998; National Science Board 2000; Russell 1994; Sanchez 1997). For example, many individuals operate with the misconception that antibiotics can help treat a viral infection and that having a flu shot immunizes against the various different strains of the virus. For some time, the public believed that AIDS only affected homosexual populations and later that it could be contracted through casual contact. But it would be profoundly dangerous if these beliefs were perpetuated by teachers, because they are false. Accordingly, ID should not be taught to students merely because the public demands it. It should be discussed only if ID proponents succeed in convincing the scientific community that ID has supporting evidence behind it.
PROMOTING "GOOD PEDAGOGY"
It has been commonly argued within the context of the "teach the controversy" approach that "academic freedom" (Hacker 2004) and "good pedagogy" (Meyer 2002) demand that alternatives to evolution be taught. It is ironic that ID supporters appeal to these notions to support the inclusion of anti-evolution evidence, considering that biology teachers avoid teaching lessons pertaining to evolution because they fear reprisal from politicians and from parents (Jacoby 2005). Some school administrators have even recommended to teachers that they sidestep the topic (Dean 2005). Further, the Georgia State Superintendent of Schools, Kathy Cox, temporarily removed the term "evolution" from Georgia's science standards "to give teachers some leeway to teach it without having to use a word that antagonizes some parents," (Tofig 2004). In Dover, Pennsylvania, an administrator had to read the district's policy on "intelligent design" to students because teachers refused to do so (Anonymous 2005).
A profound cost associated with distorted arguments against evolution is that widespread misunderstanding about and ignorance of evolutionary theory endure. According to a study by Lawrence Lerner, evolution is poorly treated in the state science standards of at least a third of US states (Lerner 2000). It seems to be the case that American students do not receive adequate instruction about the fundamentals of evolution and do not appreciate how integral evolution is to numerous scientific and non-scientific fields. As a result, misconceptions about evolution are abundant, including the notion that humans are merely a product of "random chance", that evolution is inconsistent with laws of thermodynamics, and that there are no transitional fossils (Rennie 2002).
This is not to say that evolutionary theory is untouchable. As mentioned previously, there are certainly active controversies about evolution and gaps in biologists' explanations. Rather, it is to assert that evolution must be understood thoroughly by students before its merits can truly be assessed. Yet since many students may only be learning a caricature of evolution or perhaps nothing substantive about it, teaching them about challenges to evolution might not be very meaningful (Moore 2001).
IS THE PROPOSED SOLUTION WORSE THAN THE ALLEGED ILLNESS?
Even though the "teach the controversy"approach has its flaws, the question still remains whether it is warranted to discuss "intelligent design" specifically in biology classrooms. ID proponents contend that their view is scientific and thus should be taught alongside evolution. They claim that design arguments are more attuned to scientific evidence than older versions, including the ones offered by William Paley. Indeed, instead of doing original research, ID proponents have dedicated much time and effort to identifying problems with evolution and suggesting how design might be compatible with a scientific picture of the world.
However, it is difficult, if not impossible, to disentangle ID from discussions about religion. Even if ID proponents could be taken at their word that ID could be taught without religious overtones (Behe 2005), questions about the designer will inevitably emerge. Metaphysical and religious assumptions built into any version of ID are not easily separable from the "scientific" lessons that would be offered to students. For example, one of the chief assumptions built into current formulations of "intelligent design" is that the designer is a single entity or "intelligent agent", which means that some contemporary views about the nature of the designer(s) are dismissed. Of course, monotheism tends to be the preferred view of ID supporters but one could legitimately question whether that assumption should be granted and whether it is appropriate to allude to one subset of religious views at exclusion of others. As Hume asks, "Why may not several Deities combine in contriving and framing a World?" (Hume 1779: 192).
Discussion of ID in a classroom opens, perhaps unintentionally, the door to religious conversation about the identity and traits of the designer. Yet it is not clear that it would be wise for biology teachers to stray into religious instruction. Even if a biology teacher can successfully dodge questions about the nature of designer, how will teachers explain the causal mechanisms of the design process? ID proponents do not offer much in the way of an explanation. Creationists, for example, offer a forthright and direct answer on this issue. Duane Gish "bites the bullet", so to speak, and argues, "We cannot discover by scientific investigations anything about the creative processes used by the Creator" (Gish 1979: 40).
Assuming that evolution is accepted to some degree, which ID proponents largely say that they do, at what point do the designer's actions end and evolution begin? One potential hypothesis is that the designer was involved in the initial formation of the universe and that ended the designer's role. Another hypothesis is that the designer is continually involved in designing the universe. Alternatively, the designer may act intermittently. On what basis should a biology teacher (or any human for the matter) distinguish between these competing explanations? Yet it seems crucial that we have some means to sort through these explanations if ID is to help us understand better how the universe works.
CONCLUSIONS
When the issue of evolution emerges in the classroom, students should not be left with the impression, with which much of the current debate might leave them, that evolution is scientifically "controversial" and that it is the only area of science where scientists themselves have disputes. In all these issues, the current crop of "intelligent design" proposals significantly misleads students regarding the nature of science and the evidence for evolution. Teaching that evolution is dubious or controversial within the sciences does the students a disservice because the "controversy" is over how science is to be understood and applied in modern society.
If the outgrowth of the legal, religious, and scientific disputes about evolution leads to the emergence of a high school class dedicated to the intersection of science and values, that would be a welcomed addition. Considering how central science is to our lives and how often its social, moral, and religious implications are not examined thoroughly enough, a class that looks at the broader aspects of scientific disputes might be a wise — and desirable — approach.