Zero Cheers for Intelligent Design Creationism
In "Two Cheers for 'Intelligent Design,'" David Moulton revisits the Bush-era culture war over alternatives to Darwinism. He thinks ID's arguments should have been taken more seriously. I disagree.
Everything old is new again.
When I was working on my book about Christopher Hitchens, I took it for granted that the version of America’s culture war that gave rise to “New Atheism” was dead and gone and it was never coming back. The culture war itself isn’t going anywhere. But it’s not going to be fought over that particular terrain.
This week, the universe seems to be determined to prove me wrong. The state of Louisiana announced a daring daylight raid on Jefferson’s “wall of separation” between church and state. Republican Governor Jeff Landry signed a law on Wednesday that mandates the display of the 10 Commandments in every public school classroom in the state—“from kindergarten to state-funded universities.” The ACLU immediately announced a lawsuit.
And, almost at the same time, Compact published an attention-grabbing essay by David Moulton called “Two Cheers for ‘Intelligent Design.’” In it, Moulton revisits the Bush-era battles over “Intelligent Design” as an alternative to Darwinian evolution. Moulton never quite endorses either the substantive claims of ID or the common Bush-era proposal that it be taught in public schools as one half of an allegedly live “scientific debate.” But he does strongly suggest that ID’s advocates were serious thinkers who were unfairly ignored or maligned in that era—and that their ideas deserve to be revisited now.
I’m not convinced.
Moulton opens with an anecdote about his high school years:
As a budding leftist and secularist…I remember bristling when a 10th-grade classmate gave a presentation in support of so-called Intelligent Design, the claim that the complexity of nature was better explained by the existence of a creator than the workings of natural selection. This wasn’t because I was particularly knowledgeable about evolutionary biology, but because I knew that for members of my political tribe, Charles Darwin’s theory was sacrosanct.
As it happens, I don’t think you need to be “particularly knowledgeable about evolutionary biology” to be justified in bristling at ID being treated as a scientifically credible challenge to Darwinism. We’ll get to that. But I do think that what Moulton acknowledges about his past self was true of a lot of people at the time.
I’m probably about a decade older than Moulton. I can vividly remember being home from college during this same period and watching the local TV news in my old bedroom while two members of Michigan’s state legislature debated this issue. A conservative Republican was supporting a bill to “teach the debate” in biology classes. A Democrat had been brought on to argue with him. And I can remember being shocked by how bad the Democrat was at explaining what Darwin’s theory even was. I don’t know if he even got the basic mechanics of random-mutation-plus-selective-pressure. He just knew that scientific experts believed that some sort of process of gradual change explained the lifeforms alive today without God entering into it and that was good enough for him.
But, and this is a crucial point:
The (undeniable) fact that many people on the pro-evolution side of the culture war didn’t understand the science doesn’t by itself tell us anything about whether the (many, many) scientists, philosophers, and commentators who did understand the science had good responses to the alleged challenge posed by ID.
In fact, I think they had the kind of responses anyone with a good-enough layman’s grasp of the issues should find decisive.
Moulton writes:
This was the year of the Kitzmiller v. Dover trial, which concerned a requirement imposed by the school board of Dover, Pa., that high-school biology students be read a statement suggesting that Intelligent Design, or ID, was a legitimate scientific alternative to the theory of evolution. In response, a group of Dover citizens sued the board for violating the separation of church and state by inserting religious views into science class. The case attracted national media attention… Ever since Darwin, there have been religious believers who refused to accept evolution, but Intelligent Design scholars presented themselves as different from the older brand of creationists. Rather than relying on a literal interpretation of scripture, they crafted philosophical and scientific arguments to make their case. Most of the time, they didn’t speak of the Christian God or even God at all, instead referring to an unspecified “intelligent agent.”
Let’s talk about those “philosophical and scientific arguments.” Moulton explores two—irreducible complexity and specified complexity.
It might be worth doing a followup essay on specified complexity but I’ll focus here on irreducible complexity, which Moulton introduces through the work of ID advocate (and star witness at the Dover trial) Michael Behe:
Irreducible complexity refers to the fact that machines often require many parts working in concert. Take away one part, and you don’t just reduce functionality—you destroy it. This poses a problem for Darwin, because his theory only allows for piecemeal innovations over many, many years. Chapter 6 of On the Origin of Species acknowledges that at first, it seems absurd to suggest that an organ as intricate as the human eye could have evolved by natural selection. But that didn’t stop Darwin from speculating that at some point a nerve could have become sensitive to light and then gradually grow more and more complex to finally become an eye. Since the 19th century, creationists and evolutionists had been arguing back and forth on this question.
In Behe’s view, the debate was taking place on too general a level. Each side was spinning just-so stories about how evolution could or couldn’t have happened. By the 1990s, however, we knew enough about biological systems to see if they could have evolved according to Darwinian mechanisms. Behe devoted the second part of his book to examining a series of molecular machines. These include the tail or flagellum that single-cell bacteria use to swim, as well as intracellular transportation systems used in human immune response. He finds these machines require multiple proteins, each of which would have had to evolve separately. An organism that had to rely on Darwinian evolution would simply die off long before it had any of the functional parts necessary to survive.
I just want to pause here to note that this is all Moulton says about irreducible complexity. He says an awful lot, though, about the sneering contempt of many biologists and philosophers of science for ID. He delves into the belief held by many of them that ID was a “trojan horse” for the culture-war agenda of evangelical Christians.1 He quotes several expressions of embarrassment from Darwinists about what it said about American culture that this was even a subject of debate. He quotes Behe’s ID comrade Stephen Meyer, who told Moulton that “he and his colleagues ‘got canceled before getting canceled was cool.’” And Moulton says that it’s a pity Meyer’s work “isn’t more widely read and discussed.”
All of this paints a picture that’s accurate to a point—there was indeed plenty of sneering—but is, in other ways, wildly off-base. In fact, Meyer’s book Darwin’s Doubt got such a flood of substantive responses that the Discovery Institute’s David Klinghoffer cited the sheer volume of criticism as verification for the DI’s contention that there was in fact a live scientific debate about Darwinism vs. Intelligent Design:
It's now evident that, their previous denials notwithstanding, Darwin defenders have been unnerved by Darwin's Doubt. On the same day last week, both the world's top newspaper (the New York Times) and one of the world's top scientific journals (Science) turned their attention to the problem posed by Stephen Meyer.
How about irreducible complexity? Is it true, at least, that Darwinists had no substantive reply to that argument?
You’d certainly think so from reading Moulton’s essay, but the reality is that not only did Bush-era Darwinists have a good response to it, but Darwin already had the broad outline of that respose in 1862. He wrote:
Although an organ may not have been originally formed for some special purpose, if it now serves for this end we are justified in saying that it is specially contrived for it. On the same principle, if a man were to make a machine for some special purpose, but were to use old wheels, springs, and pulleys, only slightly altered, the whole machine, with all its parts, might be said to be specially controved for that purpose. Thus throughout nature almost every part of each living being has probably served, in slightly modified condition, for diverse purposes, and has acted in the living machinery of many ancient and distinct forms.2
What Darwin was getting at here is what evolutionary biologists later called exaption. A trait that natural selection favors for one “purpose” is later coopted for another.
Michael Shermer, who is not my favorite guy but who was always good at accessibly explaining this sort of thing, gives the example of wing evolution in his 2006 book Why Darwin Matters: The Case Against Intelligent Design. "Fully formed wings are obviously an excellent adaptation for flight that provides all sorts of advantages for animals who have them,” he writes, “but of what use is half a wing?”
Well:
The incipient stages in wing evolution had uses other than for aerodynamic flight--half wings were not poorly developed wings, they were well-developed something elses--perhaps thermoregulating devices. The first feathers in the fossil record, for example, are hairlike and resemble the insulting down of modern bird chicks. Since modern birds probably descended from bipedal therapod dinosaurs, wings with featers could have been employed for regulating heat--holding them close to the body would retain heat, stretching them out would release heat.
Similarly:
As for the bacterial flagellum, although it is a remarkable structure, it comes in many varieties of complexity and functionality. Bacteria in general may be subdivided into eubacteria and archae-bacteria; the former are more complex and have more complicated flagella, while the latter are simpler and have correspondingly simpler flagella. Eubacterial flagella, consisting of a three-part motor, shaft, and propeller system, are observedly a more complicated version of archabacterial flagella, which have a motor and a combined shaft-propeller system. To describe the three-part flagellum as being irreducibly complex is just plain wrong--it can be reduced to two parts--and disingenous. Additionally, the eubacterial flagellum turns out to be one of a variety of ways that bacteria move about their environment. For many types of bacteria, the primary function of the flagellum is secretion, not propulsion. For others, the flagellum is used for attaching to surfaces and other cells.
...[P]lylogenetic studies on flagella indicate that the more modern and complex systems share common ancestors with the similar forms. So here an evolutionary senario presents itself: archaebacteria flagella were primarily used for secretion, although some forms were exampted for adhesion and propulsion. With the evolution of more complicated eubacteria, flagella grew more complex, refining, for example, the two-part motor and shaft-propeller system into a three-part motor, shaft, and propeller system that was then exapted for more efficient propulsion.
Behe likes to illustrate irreducible complexity with the example of a mousetrap—take out any one part of the contraption and it doesn’t work to trap mice. The biologist Ken Miller notoriously showed up to testify at the Dover trial wearing a necktie with a piece of a mousetrap used as a tie clip to cheekily illustrate Darwin’s point about exaption.
So the premise of the irreducible complexity argument is a bad one. More importantly, though, even if the premise were far more credible, the inference itself would be terrible. This is pure uncut God of the Gaps stuff—we haven’t figured out how such-and-such happened yet, so it must have been divine intervention. Science being an eternally incomplete search for truth, you can always find gaps to plug “that part was divine intervention” into if that’s your thing, although as old gaps are filled you end up having to constantly adjust God’s placement.
As more than a few religious believers have pointed out over the years, there’s something a bit undignified about reducing God to the status of a bit of theoretical putty to fill in the (alleged) cracks in a scientific structure. And whether or not it’s good theology, it’s an awful way to approach scientific inquiry.
I’m not terribly interested in the traditional “phil of science” question of differentiating science from non-science on a priori grounds. Most famously, Karl Popper thought you could do that with refutability—in order to count as science, it has to be clear what would count as a refutation—but there are various problems with that you can read about here. Whether or not ID is excluded from “counting as” science on Popperian or some other grounds, though, the more important point is that God of the Gaps theorizing is excluded from being credible science for reasons a few seconds of thought should be sufficient to bring out.
First, there’s a pretty basic logical fallacy at the heart of the whole thing. Problems for Theory A aren’t in themselves evidence for Theory B, particularly without some sort of guarantee that A and B are the only options. This was, in fact, a crucial point in the consideration of whether ID was an alternative scientific theory to Darwinism—rather than a cheap attempt to smuggle God into public-school classrooms—in the Dover trial:
[T]he concept of irreducible complexity is ID's alleged scientific centerpiece. Irreducible complexity is a negative argument against evolution, not proof of design, a point conceded by defense expert Professor Minnich. (2:15 (Miller); 38:82 (Minnich)) (irreducible complexity "is not a test of intelligent design; it's a test of evolution"). Irreducible complexity additionally fails to make a positive scientific case for ID…
You can try the cheap trick of dividing things up into “naturalistic explanations” and “supernatural explanations” and say the (alleged) problem with explaining the stepwise evolution of bacterial flagellum is therefore evidence for a supernatural explanation—since those are the only two possible options—but this is no better than dividing the space of possibilities into “explanations involving the invention of bacterial flagellum by alien scientists doing an intergalactic research trip” and “explanations not about alien scientists.”
Second, the alien scientists explanation is something that, although it’s not very plausible given the actually existing evidence, could in principle be the beginning of a fruitful scientific investigation, because we could discover fossilized pieces of their discarded spaceships, do some reverse engineering, try to figure out what part of the cosmos they came from, and so on—while “divine intervention” is just an explanatory wall. Where does further scientific inquiry go from there?3
The recommendation, in other words, is that when we (allegedly) don’t have an explanation of how some biological structure evolved, we stop looking. The equivalent would be a CSI team investigating a murder not being able to figure out the logistics, concluding that whatever suspect they’d already settled on must have used magical powers, and calling it a day.
“Specified complexity” is, at its core, the idea that when given elements—whether letters of the alphabet or the bases in DNA—are arranged in patterns displaying a certain level of complexity, it’s rational to infer that this was a product of design by an intelligent agent. The Discovery Institute’s William Dembski was so confident about his specific formulation of this argument—with a superficially mathematically sophisticated Explanatory Filter—that he put it forward as a Fourth Law of Thermodynamics. But strikingly, no normal researcher working in information theory seems to find it useful in any context whatsoever.
So, as with irreducible complexity, we have premises with very little buy-in from most of the people with relevant subject-matter expertise.
But, also as with irreducible complexity, that’s not the biggest problem.
The biggest problem is that it’s just more God of the Gaps—taking a place where (allegedly) we don’t yet have a naturalistic explanation of the data and simply concluding, in the words of this very mean but very funny clip, that “magic man done it.” And that’s not an alternative scientific theory, supported by its own body of evidence, generating paths for future research, and so on. It’s just a fancy way of noticing a (real or alleged) problem with an actual program of scientific research and proposing that we throw up our hands and stop trying.
Look:
As Moulton learned when he interviewed Meyer for the Compact essay, and I learned twenty years ago when I was a graduate student at Western Michigan University and another Discovery Institute guy, the philosopher of biology Paul Nelson, came there to give a talk, these guys are clever, well-read, and extremely articulate. They’re possessed of both thoughtful demeanors and a winningly nerdy passion for this kind of in-the-weeds intellectual debate. I don’t deny any of that. In fact, I take it for granted that the DI wouldn’t wouldn’t have recruited them if they lacked these qualities. But that itself tells you exactly nothing about the quality of the underlying ideas.And all of those underlying ideas work out to variations on a single core move:
I’ll bet you can’t explain that. But I can!
Magic man done it.
Which is, I should note, not exactly a crazy conclusion if you glance at the major funders of the ID think tank with which Behe was affiliated (the “Discovery Institute”) or read the Institute’s leaked Wedge Document from 1998.
From Darwin’s un-pithily-titled On the Various Contrivances by Which British and Foreign Orchids Are Fertilized by Insects, and on the Good Effects of Intercrossing, quoted in the Shermer below.
ID advocates have always been aware of this critique, but they’ve never had much plausible to say about it. Meyer, for example, comes up with a dozen “predictions” supposedly based on ID theory in Signature in the Cell but these tend to be hopelessly vague and in any case certainly aren’t anything that even look like scientific predictions in the usual sense. There’s a useful summary here.