Tuesday, September 27, 2005

Teaching the Controversy by Teaching Darwin

One manifestation of the conservatives' suspicion of Darwinian science is that many of them--particularly in the U.S.--tend to oppose the teaching of Darwinian evolution in public school biology classes unless "intelligent design theory" is also taught.

Yesterday, a U.S. federal court in Harrisburg, Pennsylvania, began taking testimony in a dispute over the teaching of "intelligent design" in public school science classes as an alternative to Darwinian evolutionary science. The school board in Dover, Pennsylvania, wants to require that "intelligent design" be introduced into ninth grade biology classes. Some parents have filed a suit claiming that this violates the First Amendment to the Constitution by promoting "an establishment of religion." Defenders of "intelligent design theory" claim that it is a truly scientific theory that does not depend upon religious belief.

This case could eventually be appealed to the U.S. Supreme Court, which would continue an endless debate over the public school teaching of evolution that began eighty years ago in the famous "Scopes trial" in Tennessee in 1925.

This debate has reached an impasse. I have a proposal for breaking this impasse, a proposal that I briefly lay out in my book Darwinian Conservatism.

Proponents of intelligent design at the Discovery Institute (a conservative think-tank in Seattle) have adopted the argument of "teaching the controvery." Why not teach the theory of evolution by natural selection along with intelligent design theory, so that students are fully informed about all sides of this debate?

Opponents respond by saying in effect, "What controversy?" There is no real scientific controversy over the theory of evolution. The supporters of intelligent design theory are moved not by scientific motives but by religious motives. And after all, intelligent design theory is not really a scientific theory, because it appeals to supernatural causes beyond natural experience and the scientific method.

Here's my proposal. Let's "teach the controversy" by teaching Darwin. We could have high school students read selections from Darwin's ORIGIN OF SPECIES and DESCENT OF MAN, along with some modern textbook in evolutionary theory such as Mark Ridley's book EVOLUTION (Blackwell Science).

Surely, the proponents of evolution couldn't object to having students read Charles Darwin. And yet this could also satisfy the proponents of intelligent design, because Darwin himself presents intelligent design theory as the major alternative to his theory.

In the ORIGIN OF SPECIES, Darwin frames the fundamental issue as a controversy between two theories--"the theory of special creation" and the "theory of natural selection." He indicates that until recently "most naturalists"--including himself--have accepted the "theory of special creation," which says that each species has been independently created by an Intelligent Designer. But Darwin thinks that now we have a better theory--a "theory of natural selection," which says that although the primary laws of nature may have been created by an Intelligent Designer, those general laws allow for the natural evolution of species by natural selection without need for special interventions by the Designer to design each species and each complex organic mechanism.

Darwin indicates that neither theory can be conclusively demonstrated. But we can at least judge one theory as more probable if it can explain "large classes of facts" more intelligibly than the other theory. For example, if the "theory of natural selection" can explain the geographic distribution of species between the Galapagos Islands and the South American mainland and do this more persuasively than any alternative explanation based on the "theory of special cration," then we can judge the evolutionary theory to be more probable.

Darwin acknowledges that there are many "difficulties" with his theory, and they turn out to be the very difficulties that are commonly stressed by proponents of IDT. But while Darwin admits that these difficulties are so severe as to be "staggering," he tries to answer these difficulties, while arguing that the theory of special creation has its own difficulties.

The prominence that Darwin gives to the theory of special creation as the alternative to his theory explains why Philip Appleman, the editor of the Norton Critical Edition of Darwin's writings, decided to include in the 3rd edition selected writings from Philip Johnson and Michael Behe--two proponents of IDT. Appleman recognizes that the debate over IDT continues the debate seen by Darwin himself.

Of course, the evidence and arguments for evolutionary theory have deepened since Darwin wrote. After all, Darwin didn't even understand the genetic mechanisms underlying evolution. So it would be good to have high school students read some modern survey of evolutionary science. But here again they could see the same fundamental controversy presented by Darwin.

Mark Ridley is a biological anthropologist at Emory University. His book EVOLUTION is one of the leading introductory textbooks in evolutionary theory. When he surveys the "evidence for evolution," he suggests that we need to distinguish "three possible theories of the history of life"--evolution, transformism, and creationism. According to the theory of evolution, all species have evolved from a common ancestory, and they change through time. According to the theory of transformism, species have separated origins, but they change over time. According to the theory of creation, species have separate origins, and they do not change.

Ridley argues that the evidence supports the theory of evolution as superior to the other theories. Students who would read this could thus see the controversy between evolution and special creation and judge for themselves whether Darwin, Ridley, and others are right in arguing for the superiority of evolutionary theory.

Recently, I presented my compromise proposal on a panel at the convention of the Association for Politics and the Life Sciences in Washington, D.C. Chris Mooney, the author of THE REPUBLICAN WAR ON SCIENCE, was on the panel. He complained that it would not be right to allow high school students to think through these issues for themselves, because only scientific "experts" could judge the evidence for evolution. As far as he was concerned, the purpose of high school science education was to tell students what the "experts" believed, and any proposal to open up the classroom to real debate was actually part of the war on science coming from the Religious Right and George Bush.

In my book, I give my reasons why I think that the arguments for IDT as a substitute for Darwinian science are weak, and why conservatives need to see Darwin as their friend and not their enemy. But, still, I see nothing wrong with allowing students to debate these issues for themselves, which might actually teach them how to weigh scientific arguments over issues with deep moral, political, and religious implications. Shouldn't that be the purpose of public education in a free republic?


Anonymous said...

Dear Larry,
Sounds Fair and balanced style. To me ID is a religious theory and Evolution is a science theory. Would most teachers see it this way? Would they teach it this way? I can see most teachers unable to deal with ID in a way that would make students understand the difference in religion and science.

Mark Griffith

Larry Arnhart said...


Yes, I agree that it might be difficult to find high school teachers who could handle the sort of class that I have in mind. Most teachers would probably prefer a standard textbook in biology over Darwin's original texts.

But I do believe that some teachers--particularly, those teaching "advanced placement" courses--would enjoy the challenge and stimulation from leading discussions centered on reading Darwin's texts.

Actually, almost anything would be an improvement over what we have now. Most high school biology teachers simply avoid the whole topic of evolution, because they're afraid of stirring up too much controversy.

Anonymous said...

What students need first is some solid grounding in scientific method, so they can understand how scientists test and discard competing theories. Then they can understand why ID is not ultimately testable and therefore not scientific.

Don't waste time responding to a party hack like Mooney. He doesn't care about science or truth, only what advances liberal Democrats.

Larry Arnhart said...

I agree with you about Mooney, whose writing seems to be little more than mindless political polemic.

I also agree with you that students need to learn how to employ the scientific method. A good way to do that is to study the argumentation of a great scientist like Darwin.

When they compare Darwin with his "intelligent design" critics, they might see that they employ a purely negative rhetoric that fails to offer any positive theory that could be tested. Exactly where, when, and how did the intelligent designer create "irreducibly complex" mechansims of life? They have no answer to such questions.

Tony Bartl said...

Dr. A,
I have long been impressed and fully persuaded by your position here. I have yet to the see evidence to persuade me that the Darwinian account is true, but I must now admit that is has some merit--though I think it is exaggerated, even by you. In school I, along with virtually every other child in America, were simply told it was true. Authority vs. authority. This is also true of the big bang theory, stellar evolution, planet formation, the fossil record, and the ages of the planet and the universe. There was simply no reason for me to accept any of these things. Most children excepted them, not for any good reason, but because they had no competing authority which could match that of their teachers and the almighty "They" who know these things, i.e., "the scientists." After weighing the evidences, I now fully accept all of these except Darwinism, though I no longer find it as implausible as I did as a child.

Tony Bartl said...

I wrote excepted when I meant accepted. that is embarrassing

Anonymous said...

Adoption of your proposal in some states or counties seems to become more probable to the extent that the Americans return to federal orders, and a return to federal orders seems more probable as the "federal" government exhausts its remaining financial resources.