Posted by Jason Rosenhouse on February 16, 2007 08:27 PM
Skeptic Magazine publisher Michael Shermer debated William Dembski yesterday in Bridgewater, VA on the subject of evolution vs. ID. Since Bridegwater is a short drive away from my digs in Harrisonburg, I decided to go check it out.
The debate was held at Bridgewater College, a small liberal arts school affiliated with the Church of the Brethren, as part of their Anna B. Mow Lecture Series. According to the small program handed out at the door, “The Anna Beahm Mow Symposium honors Dr. Mow as a teacher who walked with her students, a scholar whose life was a pursuit of knowledge, an author who conversed with her readers and a Christian whose love of her Lord enabled her to be accepting of all children of God.”
The site was a small theater, filled with roughly 150 people. The format called for each speaker to present an opening statement of twenty minutes (I wasn't actually timing things, but it felt like twenty minutes at any rate.) Then there would be a round of questions from the audience. Finally, there were five minute closing statements from the speakers.
Dembski went first. Curiously, in his Power Point presentation he identified his institutional affiliation as the Discovery Institute, as opposed to the small Texas seminary where he actually works. As is typical in such venues, it was the calm, faux-reasonable Dembski who showed up, not the lunatic, frothing-at-the-mouth Dembski so familiar from his writings and blog posts. He titled his presentation “Blind Evolution or Intelligent Design?” He was keen to emphasize the significance of the word “Blind.” ID, you see, is not hostile to the idea of evolution viewed as common descent or change through time. It merely rejects the idea that a blind process like natural selection could be the cause of it.
From here he launched into the usual ID tripe: Can Darwinism explain the origin of genetic information? What about irreducible complexity? Functional biochemical machines are islands of fucntionality in an ocean of non-functionality! Just look at the flagellum for heaven's sake!!
Next up was a video allegedly showing the complexity of what goes on within the cell. Animated, personified proteins carried out various incomprehensible tasks while a voice-over provided rapid-fire, jargon-laden descriptions of what was going on. I'd be curious to know what effect this video had on the audience. To me it seemed an obvious snow-job. No one other than a professional cell biologist could have followed the presentation. It was strictly an attempt to get the audience to say, “Gosh! That's really complex!” On top of that, the whole exercise seemed a bit patronizing. I came to hear Dembski speak, not to be plunked down in front of the television.
Moving on. Compared to that, the flagellum comes off looking simple! The ribosome is even more complex!
Then came a tremendous onslaught of mechanical metaphors for the goings-on in a cell. I only had time to jot down: Self-replicating robotic manufacturing plants, Information processing storage and retrieval, and Automated parcel addressing (UPS labels), before he was on to the next slide. Needless to say, the cell does not actually contain any of those things. Instead it contains a collection of proteins doing whatever it is proteins do when properly organized. But the metaphors can be useful for bamboozling people.
Next up came some talk about the flagellum and the Type Three Secretory system. Dembski argued that it's not enough to identify one possible stepping stone toward evolving a flagellum. Rather, a “complete, fully articulated evolutionary path” is required. Required for what, one wonders? Unless we can spell out every step in the evolution of a complex system we should accept ID? It goes without saying, of course, that Dembski provided only a caricatured version of all that is known about flagellum evolution.
Then came the quotes about how there are currently no detailed Darwinian accounts of structures within the cell. It was the usual ID suspects: Shapiro, Harold, Griffin and so on.
Around here Dembski provided his definition of ID: ID is the study of patterns in nature that are best explained as the result of intelligence. Which is odd, because in his writing he has been known to say things like, “Inetelligent design is just the Logos theology of John's gospel restated in the idiom of information theory.” I wonder why he didn't use that definition?
Somehow Dembski never got around to explaining how that study is meant to be undertaken. Once you have decided the pattern is the result of design, ID seems to have little to offer. Dembski might better have said that ID is the search for patterns believed, for little reason, to be the product of design. Better still would have been the most honest answer: ID is the search for a method of having religion taught in public schools without having some uppity judge lecturing them about the constitution.
Dembski closed with a whirlwind tour through his own prattlings about specified complexity. He rather amusingly showed a clip from the movie Dumb and Dumber. You know the one I mean. Jim Carrey asks Lauren Holly what the chances are that a guy like him could end up with a girl like her. “Not good,”she replies. “Not good like one in a hundred?” “More like one in a million.” Pause. “So you're telling me there's a chance! Yeah!!” Very amusing. Definitely the high point of his presentation. This was meant to show the absurdity of evolutionists relying too much on blind chance.
Moving on. Here's a picture of the cover of The Design Inference! Here are the first pages of some peer-reviewed papers I claim support ID! There's a real debate over this in the scientific community! Thanks.
Then came Shermer. He organized his presentation around five basic pricniples. First up: Before we say something is out of this world, make sure that it's not in this world. The point was simply that you don't glom onto a fantastic, supernatural explanation when a natural one will suffice. He illustrated this point with some humorous examples. He showed a picture from the Weekly World News showing a picture of Arnold Schwartzeneggar shaking hands with an alien. Surely the explanation that the WWN was making stuff up is more likely than the explanation that involves actualy alien visitation.
Point two was that the burden of proof lies with the ID folks. If we are to accept ID as an explanation, some positive evidence in its favor is required. It is not sufficient to just make criticisms of evolution. This led into point three, which was that ID folks commit the either/or fallacy. That is, they act as if the only options are either Neo-Darwinian evolution or ID.
But the bulk of the talk centered around point four, which is that evolution is etablished not by any one fact, but by a large collection of facts from disparate fields of study.
He began by showing a very detailed sequence of transitional fossils linking ancient land mammals to modern whales. He said these fossils strongly suggest an evolutionary sequence. How does ID explain it? This was a point he came back to over and over again. Evolution provides a single, coherent explanation for a wide variety of facts. If you choose to reject it in favor of ID, then say something about how ID explains these fossils. What did the designer actually do? At what point in the sequence did the designer interfere?
Then he moved on to numerous examples of vestigial structures. Evolution explains these effortlessly, but what is the design explanation? What light does ID shed on the origin of these structures?
From here he mentioned the possibility of observations that would be very difficult to work into an evolutionary picture, such as fossil trilobites in the same strata as human fossils.
Next up was the evolution of complex structures. He talked about the gradations of complexity to be found in different sorts of eyes in the animal kingdom. He also talked about the poor design, from an engineering perspective, of the eye. Once again he emphasized that this sort of cobbled together design is what you expect from evolution by natural selection, but is hard to explain from a design perspective.
Then he discussed the idea of a convergence of evidence. He used the example of using different dating methods for establishing the age of the Earth. When there is a consistency acorss many different sorts of data, we are justified in drawing certain conclusions.
He went on to discuss the evidence from genetic and molecular similarities, relying heavily on Francis Collins' presentation of these facts in his recent book.
The final point was the vacuity of supernatural explanations. Invoking unspecified, all-powerful designers just doesn't get you anywhere when you are trying to explain the natural world.
Shermer went on to provide an apt summary of ID logic: (1) X looks designed. (2) I can't think of how X was designed naturally. (3) Therefore, X was designed supernaturally. He said that ID has no substance, and that it is not a good idea to peg religious faith to assertions of the form “I hope scientists don't fill that gap!”
From here he went on to discuss some specific ID claims. He talked about exaptation as a general difficulty for notions of irreducible complexity. The picture of complex systems evolving linearly by the sequential addition of clearly defined parts overlooks the possibility of changes of function over time. He said specifically that ID assertions about the flagellum are simply wrong. The flagellum and its parts serve several functions, not just propulsion but secretion and adhesion as well. He pointed out that quite a lot is known about the genetics of the flagellum, and that there is no reason to believe it did not evolve via familiar mechanisms.
He then gave several examples of complex systems emerging from natural prcoesses. Modern languages are the result of an evolutionary process, Various sorts of self-organization lie behind some complex structures in nature, and the orderliness of a free market emerges without any central planner. In every case we obtain complexity without hypothesizing top-down design. Thanks.
That's an overview of the substance of the two presentations. But let's talk about the really important stuff: Style. Shermer was better. Now, I grant you, I'm not an unbiased source. But the fact is I'm usually very hard on the pro-evolution side in these debates. This is partly because I think evolutionists often get themselves into these debates without a proper consideration of how a debate differes from a scientific conference. It is also because I often think the evolution defender simply does not make the correct points in reply to the torrent of creationist argle-bargle.
In this case I thought Shermer acquitted himself admirably. His presentation was polished, funny, and made many good points. Dembski, by contrast, has a tendency to speak in monotone. Also, his timing was way off. He had to race through nearly half of his slides.
Next up was the question and asnwer period. As is typically the case at these debates, the questions were overwhelmingly anti-evolution. How do you know junk DNA has no function? How did transfer RNA evolve? What about these combinatorial/probabilistic arguments? How do you know those fossils are transitional? Your assuming evolution is true by even referring to them in that way! What about the origins of life?
The structure here was that questioners could direct their fire to either of the two speakers, but then the other one would have a chance to reply to the same question. This put Shermer in a difficult spot. First, he was on the defensive becuase of the hostility of many of the questions. Then, in every exchange Dembski was getting the last word.
Until the last question that is. That was when a strikingly handsome and breathtakingly eloquent (not to mention deeply humble) young mathematician approached the microphone to unleash a rhetorical tour-de-force of a question aganist Dembski.
He began by addressing the combinatorics argument from the previous questioner, explainingly patiently that you can not assess the probability of a particular DNA sequence evolving simply by treating it as a simple combinatorial object. That ignores the role of natural selection in the process, which has the effect of radically changing the probabilities of certain structures coming about. From there he unloaded a few jabs at Dembski's prior statement that at the 1966 (!!) Wistar conference, the mathematicians offered cogent arguments against Neo-Darwinism while the biologists stood around uncomprehending, muttering that we got here somehow. Showing an impressive mastery of relevant historical detail, the questioner pointed out that the biologists did considerably more than that, and that actually they pointed to specific places in the arguments of the mathematicians where they were making biologically unrealistic assumptions. The he sealed the deal by unloading a haymaker about Dembski's idiotic probability bloviations. He pointed out that the sorts of probability calculations Dembski says are essential to his theory are in fact impossible to carry out. He closed by saying the impossibility of such calculations is self-evident to people who know this subject, which is why not many scientists are impressed with Dembski's work.
Okay, you got me. The questioner was me.
Dembski's answer was bizarre even by his standards. He claimed that when the results of a probability calculation go against them the scientists all talk about biologically unrealistic assumptions. But when the numbers help their cause they are perfectly happy to tout them. He then launched into - are you sitting down? - a discussion of the Miller-Urey experiment.
Miller and Urey, you see, did their little experiment where they shot a spark through a mixture of some common chemicals that were likely to have been around in abundance on the early Earth. They produced amino acids. Scientists apparently touted this as evidence that a naturalistic origin of life was highly probable. Not the case, according to Dembski.
Bizarre, no? The Miller-Urey experiment had nothing to do with probabiilty. No one was claiming, based on the experiment, to be able to produce a number representing the probability of life arising naturally. But that is precisely what Dembski claims to be able to do in assessing the proposed evolution of the flagellum.
But let's suppose that it really is true that biologists are happy to tout the fruits of probability calculations when it helps the cause. So what? Dembski's logic appears to be that if you endorse the use of probability theory in one aspect of biology, you must also endorse every proposed use of it. As I said, tres bizarre.
Dembski closed his response by asserting, contra me, that in his work he assumes the best possible scenarios for evolution and that it was possible to carry out the calculations he was describing. So there.
There were several people lined up behind me waiting to ask questions, but at this point the host of the event said they had to move on to closing statements. I didn't jot down any notes here, having mostly lost interest. Dembski seemed to be losing interest as well, since he appeared to be sleepwalking through his statement. Shermer closed with his characteristic enthusiasm, and said bluntly that all the talk of scientific progress aside, ID was nothing more than an attempt to inject religion into public schools by clothing it in scientific garb. A fine point with which to close.
There was a brief reception after the event. I had a pleasant chat with prolific ID spokesman and blogger Salvador Cordova. I had the chance to converse with Shermer for a while. It looks like I'll be reviewing a couple of books for Skeptic. Stay tuned! As things were winding down I introduced myself to Dembski. He smiled politely but seemed uninterested in conversing.
Out to the car, quick shot up I-81, get home, pet the cats, pop in some more back episodes of House delivered courtesy of Netflix earlier that day. All in all, a pleasant evening.