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Eminent Domain Stuff

New London Update (2/24/06)
Coverage of the Rally at New London's City Hall (w/ pics)

Monday, November 15, 2004


Evolution vs. Intelligent Design: Round 11

Recently I've been giving some more thought to the underlying issues of the Evolution vs. ID debate. Since the data we have available neither confirm nor refute either 'theory' completely, we are left to either argue minutea or grand concepts, neither of which really resolve the issue. So, in this post I am going to make an attempt to lay out why I think Evolution is closer to a scientific Theory than is ID, and why I think this leads directly to the conclusion that Evolution has a much better chance of being 'proven' correct than does the latter (for some discussion of what is, and is not, a Theory see what I had to say here and what David thought of it (also related)).

Here is what the ID crowd would have you believe. First off, Microevolution is perfectly acceptable. Microevolution basically theorizes that small genetic changes over a few generations in a population of organisms can lead to noticeable changes in their appearance and/or function. This is obvious if one considers the development of domesticated dogs from wolves. In this case, there is no fundamental change in body structure except for those of size, color, etc. So, we have a 'new' animal but it is so closely related to the old one that we do not see a new body plan or fundamental biochemical or genetic differences.

IDers, however, claim that even many instances of Microevolution over time in a population cannot account for the great diversity of Life we see all around us. It is somewhat unclear, to me at least (and perhaps this is because there is no consensus among the ID crowd) just how insufficient Microevolution is to produce Macroevolution. Some argue that new body forms cannot be attained by Evolution while others focus on Evolution's inability to produce irreducibly complex systems. However, I think that the development of new body forms is dependent on new irreducibly complex (IC) systems, so let's focus on that.

Michael Behe is the first person I ran across arguing that IC systems cannot be constructed by small changes being positively and/or negatively selected over time (i.e., Evolution). As a matter of fact he devoted an entire book to the topic. He argues that only IC systems are outside the productive power of Evolution and he readily asserts that non-IC systems could easily be constructed by natural selection acting on genetic variation. In my experience, Behe's argument is the ID argument phrased in the most simple and basic terms. So...let's take a look at what his hypothesis requires us to accept.

Behe identifies multiple IC systems in his book and other writings. These systems' functions, he says, are 100% dependent on the function of all their components. If one is missing, the whole thing falls apart. This sounds like a very formidable problem for Evolution to overcome, and one might even be tempted to conclude that Evolution could not possibly produce such a system.

If you ascribe to Behe's brand of ID hypothesizing, then here is what (I think) you must accept. First, any IC system is identified by virtue of the fact that....what? We point out IC systems based on what criteria? The only criteria that I can find support for is this: A system is IC if Michael Behe cannot think of a way that it could be constructed in small steps. So what happens if, as I have asked previously, he's wrong in identifying one or more of his example systems as IC? If someone demonstrates that one of his IC systems could be constructed by Evolution, would the entire Intelligent Design hypothesis be refuted...or just that one example? Based on the fact that there are no set criteria for defining an IC system, I suppose the answer is that only that one example would be refuted. But, don't forget that this also implies that every supposedly-IC system is vulnerable to similar demonstrations of non-IC-ness.

So, in order to believe that ID is correct based on the IC argument, one must assert that:
1) Only IC systems are outside the creative power of Evolution.
2) IC systems are not identified by any definable criteria, but that's ok because we trust Dr. Behe's judgment.
3) All IC systems are the special and unique creation of God (or some supernatural being).

So, someone might very well come back with the fact that not all ID adherents fall into Dr. Behe's particular camp. They might very well argue all sorts of other theories dealing with the specifics of ID. So, here are the things one must believe to adhere to ID of any variety:
1) Evolution is insufficient to produce the many species and body types of Life.
2) Those species and body types were each produced in special, unique (i.e., one-time-only) events by God (or Whomever).

Either way the common feature of all ID arguments is that, at some time in the past, a Being with powers we do not (cannot?) understand created all __ (IC systems or species/body types). While this is a perfectly reasonable thing to believe it is, by definition, not science.

While David has pointed out that Macroevolution is not technically a Theory because it (supposedly) fails to provide testable predictions, it seems to me that it is at least a testable hypothesis whereas ID is not. You can argue all you want, but if ID posits that God created each species (or each IC system) individually then we have what amounts to as a bunch of miracles. Science, as I've mentioned before, has absolutely nothing to say about miracles. That does not mean that the existence of miracles is denied by science, but only that science cannot have anything intelligent to say about them since they are, by definition, not reproducible. So, in order to define Intelligent Design as a scientific theory (or even hypothesis) we would have to agree to interject miracles into a working model. Specifically, the model would go something like this:

Natural Selection acts on genetic variation to produce most systems except those that are Irreducibly Complex. When needed for the continued Evolution of Life, IC systems are created by an unknowable mechanism, allowing Evolution to continue.

Such a model would necessitate a total redefinition of what we mean by Science. While this is not, a priori, unacceptable I think that we should hold off undertaking such drastic measures if we have a simpler model that fits not only data but also the fundamental nature of Science itself.

Enter Evolution. It advances the idea that not only is the event of speciation (or creation of a new supposedly-IC system) is possible invoking simple and reproducible events. Further, it is entirely within the realm of possibility that we might just be able to recreate the defining event of Macroevolution in the lab, namely speciation or demonstrate that a supposedly-IC system is, in fact, Reducibly Complex. While these are certainly not trivial tasks, there is no principle inherent in the Theory of Evolution that rules this out as a possibility. The same cannot be said for Intelligent Design.

In conclusion...there are things in this universe we might be completely incapable of understanding. This does not mean, however, that we should identify the really tough problems, figure that they're unsolvable and just give up.


Something just occurred to me that should have been obvious before. Much has (rightly) been made of Evolution's (in)ability to make testable predictions. This is true in a strict, laboratory sense. However, there are other ways to skin a saber-tooth tiger. In addition to predicting the outcome of yet-to-be-done experiments, a Hypothesis or Theory can also be evaluated by its ability to predict the a yet-to-be-made-discovery. A case in point is this paper reporting a fossil that appears to show one of T. rex's little cousins with feathers. Apparently (and I'm taking the word of the authors here), this characteristic had been predicted prior to the discovery of an actual example. This prediction was made based on the assumption that dinosaurs evolved into modern-day birds. This single datum supports Evolution being defined as a Theory as opposed to a Hypothesis or just a some crazy ranting of a guy from the 19th century.


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