Intelligent Design: The Glass is Empty
The latest ploy of "evolution deniers" is the notion of "Intelligent Design", being promoted as a "scientific theory" worthy of (a) replacing the theory of evolution, and (b) sitting alongside Newton's mechanics as one of the great ideas of science.
It has a few problems.
As an argument purportedly about "intelligence", ID is pretty "dumb". Upon careful examination it is revealed as a "con", so cleverly constructed that it's hard to see it as anything but a deliberate fraud. It is something like the magician's illusion, distracting and misdirecting the attention of the audience, while hiding the nature of the deception and the hanky-panky skillfully executed where the audience doesn't notice. And the result isa miracle! Like all magicians' tricks, the result is, as perceived by the audience, an apparently impossible event. That's the definition of a miracle.
The intelligent design hypothesis, stripped to its essential core, is this: Physical and biological systems observed in the universe result from purposeful design by an intelligent creator.
If this is to be taken seriously as anything more than an unfounded assertion, it must be supported by evidence that specifically supports this hypothesis (excluding all other alternatives), supporting logical arguments, and it must make predictions that lead to testable experiments that could confirm or deny it conclusively.
So what exactly are the arguments put forth in favor of "Intelligent Design" (ID)? That depends on whose book you read, for they present the arguments with subtle, but important, differences. That's curious. If you want to know about any established theory in a real science, like physics, you will find it in textbooks stated consistently and clearly, though sometimes at book length. Among scientists, there's usually universal agreement on exactly what a theory says and what it predicts. Not so with ID. In fact, as you read the different books promoting ID, it sounds more like a speculative hypothesis, without support in experiment or in established scientific laws. But here's a summary of it, as best I can present it.
Some accounts add a few intermediate steps to this argument. There are quite a few problems with the ID argument. We'll consider them one by one.
1. Complex structures. ID proponents do not deny the observation that over the long span of the earth's history living things progressed from simple forms to more complex ones. [But some creationists do.] That progression of change is called the "fact of evolution". But the ID folks do deny that this progression could have proceeded entirely by the operation of natural laws. Their quibble is about the mechanisms that slowly operate to produce complex structures from simpler ones. But so far they are unable to point to any such structures that could not have come about by natural processes.
2. Organisms well-suited to their function. It's a fact that types of organisms that are around for a very long span of time are indeed sufficiently well-suited to function in their environment. Evolutionists see this as the natural and expected result of natural processes. Species that are well-adapted to their environment, and live long enough to reproduce, will be around for a very long time. Those that are poorly adapted won't. ID proponents see adaptability as something the designer anticipated and intended, so the designer fashioned that organism for survival. The ID advocates have been notably silent about why the designer had to create so many species that became extinct (dinosaurs for example). Creationists reject the notion that any species can be the ancestor of any other species, so they must conclude that the dinosaurs had no descendents. So what was the "function" of dinosaurs in the larger picture? Indeed, what was the purpose of the entire lengthy process of evolution?
Functional utility does not imply purposeful design. Scientists see evolution as blind and without purpose. What survives in nature does so because it is "well enough" suited to its environment that it persists long enough to replicate itself (often by biological reproduction). It is not easily destroyed. Organisms that survive for long historical periods are not "perfectly suited" to anything, but only "well enough suited" to escape species destruction and extinction.
3. Irreducible complexity. Here the ID promoters cite particular examples of organisms with important features, which, if lost, would doom the organism to extinction. So, they say, how could that feature have evolved naturally, by mutations? To date, every example they have cited has been refuted by evidence from nature.
4. Improbability. Creationists like to use Henry Morris' example. He imagined a junkyard with automobile parts of all kinds strewn around. What is the probability that they could, by natural means (perhaps by being hit by a tornado), reassemble themselves into a complete automobile, which sheds its rust and emerges "showroom clean" ready to drive away? Creationists liken the improbability of such a thing to that of a human being arising from natural evolution. It's an inappropriate analogynothing more than a caricature of the processes of evolution. But it plays well with those who are uninformed about science. Creationists' probability calculations are notoriously fraudulent, for they consider only the probability of diverse parts "getting together". In physics and chemistry, things are different. There are forces that act between particles and structures, and laws of interaction that must be taken into account, as well as energy considerations. These greatly increase the likelihood of parts getting togther to form stable structures of greater complexity, and to help ensure that these stable structures persist in form and function. 
5 and 6. Design requires a designer. This is not a new assertion. It has been a part of many religions from their earliest history, and has been thoroughly refuted in a variety of ways (which we consider in a latter chapter). Permeating religious apologetics are similar examples of extrapolation from the universe to something "beyond" the universe. Setting science aside temporarily, look at this from a purely logical perspective. The "designer" assertion is saying something like "When we look at all of the things designed by intelligent human beings—machines, chemical synthesis, great works of literature, art, music, etc., we cannot imagine any of them coming into being by natural processes. Therefore those other things in the universe that show similar design and complexity must also have had an intelligent designer." It's an "argument from incredulity" and an inappropriate analogy. 
But on an even more basic level, the argument is a deceptive use of words. It equates two meanings of "design": (1) a pattern or structure that is stable, functional or perceived to be beautiful, and (2) the act of deliberately producing such a pattern or structure. Accidental combinations of parts can, without intent, purpose or intelligence, result in patterns qualifying as a "design (1)". We will consider some examples in a later chapter.
Intelligent Design Isn't Even
Of course analogies are not proofs of anything, whether in logic or in science, but this argument resonates strongly with modern creationists and intelligent design promoters. But even ID advocates provide no clear way to distinguish complex things of natural origin from complex things made by human designers. There are differences between a watch and a salamander found on the road. The watch is made of different materials—metals—not found as structural components in living things. Living things have redundant and sometimes superfluous (non-functional) design elements that a well-designed watch mechanism does not. The function of the watch is narrowly specific—to tell the time (and may have decorative function as well), but living things in nature function in a fantastic variety of ways, and many of these are imperfect and inefficient by the standards of a watchmaker. You could easily list many more differences. But are these the issue? Paley's point lies elsewhere. He's claiming that the integration of the parts of the watch is unique, and they must be put together in a particular way to achieve its intended function. Any different arrangement of the parts, or any defective or missing parts, would cause the watch to fail to function. It is this fact that Paley claims tells us that the watch was designed, and designed for a purpose. It is the accomplishment of purpose that, to Paley, implies that it had a designer.
Michael Behe's principle of "irreducible complexity" is a restatement of Paley's argument. Behe points to examples from biology that he claims would fail to function if they were missing a component, or had their components rearranged.
But what does it mean for something to "function"? It simply means that that thing interacts with other things in a particular and lawful way. How do we know that kind of interaction was in any way "intended", or whether it is able to interact due to geometry and laws of physics? Rearrange the components of a complex thing, and it still might function, but in a different manner. All we can say of complex biological structures is that they "function in some manner, or they die". Structures that survive have survived because they function in a manner that sustains them and does not destroy them. This is oversimplified, of course, for reproduction or some other form of replication is an important requirement for long-term survival of complex structures of a particular type.
There's another underlying component to Behe's version of this argument. He's saying that if evolution is a progression of small changes toward functional complexity, then at each step of this progression the organism must have been functional enough to ensure its survival. Superficially this seems fair enough. But not all functionally beneficial modifications in living things arise from earlier beneficial versions. Some arise from previously non-functional parts, or at least parts that weren't previously essential to the organism's survival, but evolve into beneficial features that do aid species survival.
Now Behe goes on to claim that there are some complex organisms that would not survive if even one or a few design elements were different, or were removed, therefore that organism could not have arisen by natural processes. He calls this "irreducible complexity." He has failed to make a convincing case for any of his examples, and has to fall back on the lack of presently known fossil evidence for certain steps in certain evolutionary progressions. But, in my opinion, all of the words spent defending and refuting this idea are simply wasted, for they distract us from the fundamental emptiness of the "designer" hypothesis.
As old as the hills is the response "If there's some 'law' that 'complex things require designers', then what intelligence designed the intelligent designer?" As obvious as this is, it is still one of the most powerful refutations of the design argument. Substitute "creator" for "designer" and it is an equally powerful refutation. Religious apologists respond by saying "The creator/designer is beyond and outside the universe, and is not subject to the same laws or logic that operate within the universe." This just digs the hole deeper. If this were so, then no logic or science could ever tell us anything about the creator/designer. This would be a supernatural entity beyond our comprehension and inaccessible to us. In any case, science could not confirm or deny the existence of any such supernatural entity. Before the intelligent design idea came along, this was the "God did it" answer to scientific questions. Now any fact of nature can be "explained" by saying, "The intelligent designer did it." This isn't science, it is magic.
Another thing creationists sweep under the rug is the fact that natural laws of force interactions, as well as energy and geometric constraints, cause some structures to be stable once formed. So, once formed, they persist, and can become the building blocks of even more complex structures. This is no mystery to physicists, for they deal with such things every day in laboratories around the world, and the mechanisms and details are well known.
We need only to look around us for examples. A tree grows from a seed. A human being evolves from a fertilized egg. A crystal grows from solution. In such cases complexity gradually increases over time, and all steps in the process are due to natural laws of physics and chemistry. No "designer" intervention is required. Defenders of the ID arguments sometimes redefine "complexity" so that they can assume that the complexity of an adult human was "already present" in the fertilized egg, because it had the "potential" to become an adult human. The whole idea of "complexity" is a slippery slope, and the word seems to be defined and used by creationists to lend credibility to an already-held but otherwise unsupported conclusion.
However, once all the physical and geometric constraints are considered, and the calculations done properly, we find that the probability of complex structures arising from simpler parts is quite reasonably well within the time scale of evolution.
So we see that the ID argument has unsupported premises and logical gaps. Creationists gleefully trumpet the gaps they perceive in the fossil record, but this ID "theory" has gaps that are more like yawning chasms. If ID has any educational value for us, it belongs in a logic course as a "bad example" of flawed logical argument. It could also serve as a bad example in a semantics course, as an example of slippery and deceptive use of words. Its appropriate place is in a philosophy course. I'll even go so far as to say it deserves brief mention even in a science course, as an example of pseudo-science, worthy of inclusion right alongside astrology, alchemy, phrenology and the "theory" of the flat earth. One can better understand what science is by also examining examples of bad or misguided ideas masquerading as science.
Intelligent design is the sort of argument a clever lawyer might have invented.
The above comments are perhaps more extensive than this subject deserves. Intelligent design isn't a valid scientific hypothesis or theory, and it isn't a law of nature. At best it's an unproven philosophical hypothesis with considerable emotional appeal to many people, but with no support whatever from experiment and/or reason
Not only can we ask questions that have no answers, we can invent fantastic answers that cannot be tested in any conceivable way. If an example is needed, here's one of my favorites.
We are accustomed to the idea that the future is inaccessible to our senses or to our philosophical inquiry. The past is not accessible either. What if the past was also illusory? Could it be that the past does not exist and never did? An intelligent designer could have created the entire universe a few minutes ago, including you and I, and given us memories of a nonexistent past. The designer could have also filled the world with evidences of many kinds, consistently pointing to a past that never was. This clever designer gave each of us memories of past experiences, consistent with memories of all of those people we interact with. It's all a vivid dream. You may consider this notion absurd, and you may say "Why should we believe such a preposterous idea?" But also consider that there's no way to confirm the truth of this idea or to refute it. Now consider that we are in the same situation with any hypothesis about any intelligent designer of the universe. It can neither be confirmed nor denied by any means at all. So why should we accept it into science? 
We have put the best face on the ID hypothesis in the last section. But when you read the books by the handful of eloquent advocates of the idea, you find that "the Devil is in the details". You come away with the impression that no two of them agree on exactly what ID claims, particularly when it comes to the all-important questions of (a) evidence for ID in nature, and (b) what ID predicts about nature. After all, they are promoting this as a "scientific notion" so they'd better agree on evidence and predictions of it.
Philip Johnson points to biology, and would have us accept that while evolution can occur on a small scale, there are gaps in the evolutionary record that only an intelligent designer could bridge. On the other hand, Michael Behe's interests focus on cells, and he argues that cells are more complex than higher level living creatures. He accepts that once the intelligent designer created cells, evolution could "take it from there" and populate the world with plants and animals of all kinds. William Dembski has issues with both of these versions of ID, and says that Darwinian evolution can't produce anything by itself. Mainstream non-scientist fundamentalist creationists ought to be unhappy with all of the ID advocates, for all versions of ID are silent on issues important to creationists: the literal truth of the Genesis flood, and a young age for the earth. In fact, ID advocates disavow any connection with the concerns of "scientific creationism". Yet creationists cheer for anyone who questions the "scientific establishment" and they don't look too closely at the details and validity of the ID arguments.
Creationists and ID advocates like to say that "Evolution is a theory in crisis" because some details of the process of evolution remain to be resolved, and there are disputes on how best to resolve them. However, those are minor details compared to the fundamental differences of opinion in the ID camp. Intelligent Design seems to be a hypothesis in chaos.
 Could biological evolutionary processes ever produce an automobile? In one sense, the notion is absurd, for biological evolution produces only biological results, and an automobile is an inanimate object. But in a broader sense, evolution has produced automobiles, for man, a product of evolution evolved a brain capable of understanding and making inanimate mechanisms sufficiently well to design and produce automobiles. In the same sense, evolution has produced such complex physical structures as termite's nests, honeycombs and spider webs. One might also cite the many chemical compounds synthesized by chemists, chemicals not found in nature.
 The argument from incredulity is "I can't imagine any way this could happen, so it must be impossible." I have had some people challenge this characterization, saying "Isn't that what scientists do when they say perpetual motion is impossible?" No, there's a huge difference. Physicists don't rely simply upon hunches. They know that things are not true just because they'd like them to be true, and things are not declared impossible simply because we can't figure out how to do them. Does that mean that we can't declare anything to be impossible in nature? No. Certain things, especially in physics, are so well understood and so well tested that we can confidently predict what's possible and what's not. We also know that certain things, if possible, would seriously violate well established and well-tested laws of physics. Most of these are a result of the geometry of the universe, such as the conservation laws of energy and momentum. Some are logical impossibilities, such as "It's impossible to make a triangle in a plane that has equal angles but unequal sides." For more about this see Nature's Impossibilities.
One method for establishing that something is impossible is to assume for the sake of argument that it is possible and work out the consequences, using known and established laws. If those consequences contradict known laws, we know that we have created a paradoxical situation that can't happen.
Analogies should never be used as part of a proof of scientific propositions. Unfortunately, too many teachers, especially in introductory science courses, use analogies as a way to illustrate a scientific process or principle, or to aid memory, leading students to think that analogy is a process of reasoning. See my document The Dangers of Analogies.
 Many expensive watches include non-functional diamond chips within, so the watch can be described as "17 jewel" and command a higher price. I refuse to get into a discussion over whether these can be said to have a psychological or economic "function".
 I am aware that the example of the illusory past has a long history. I first saw it in an astronomy book by Thornton Page. He asked the reader to suppose that creation occured five minutes ago, and noted that there was no way anyone could disprove this assertion.
Reader Harlan Cooper informs me of an earlier example. The 4th century BCE Chinese philosopher Zhuangzi illustrates this with his "dream of the butterfly":
Once Zhuangzi dreamt he was a butterfly, a butterfly flitting and fluttering around, happy with himself and doing as he pleased. He didn't know he was Zhuangzi. Suddenly he woke up and there he was, solid and unmistakable Zhuangzi. But he didn't know if he was Zhuangzi who had dreamt he was a butterfly, or a butterfly dreaming he was Zhuangzi. Between Zhuangzi and a butterfly there must be some distinction! This is called the Transformation of Things. (tr. Burton Watson 1968:49)
Many people wish to see evidence for ID in everything, and in the very existence of the universe. Someone might argue, "That apple sitting on the table is evidence for God." Oh, really? "Yes, a tree grew from a seed, and eventually produced apples, and gravity and friction keep it sitting there. Surely God controls all of those processes, and everything else we see, and even us. So how can you deny God's existence?" That sort of "reasoning" can't be debated, for it insulates itself against refutation.
Someone else may disagree, saying, "You are wrong. That apple is only an illusion, like everything else we see, and we ourselves are but illusions. We only think we think, and we only believe we 'exist'. Everything we observe is a woven web of consistent illusions." This assertion is equally irrefutable. Someone else may come along and say "You are both right. God created everything, but he did it five minutes ago. So great is God's power that he created it all with evidences of a past history it never had, and created us with memories of things that never happened, but all of them reasonably consistent. So, yes, it is an illusion, but god created the illusion. Maybe it wasn't five minutes ago, but five years ago. Maybe it hasn't been created yet, and we are just memories that will be implanted in people later. It doesn't matter, for only God knows for sure." And so it goes. All these are old philosophical arguments. None of them can be "answered" by science, nor should anyone bother. Such philosophical speculations are as unproductive as shoveling feathers or juggling eels. They lead nowhere, except to show us the futility of such speculation, and the futility of trying to obtain answers to meaningless and unanswerable questions.
Here's a good article giving a fuller account of the various ID claims and their differences. Devolution. Why intelligent design isn’t, by H. Allen Orr. The New Yorker, 5/30/2005.
Top of page.
Intelligent Design Creationism: Fraudulent Science.
Order from Disorder. Creation in Everyday Life.
Order and Disorder in Nature.
Is The Real World Really Real?
Uses and Misuses of Logic.
The Scientific Method.
Proofs of Unknowables. The Proof is Pudding.
Theory or Process?
Is Intelligent Design an Interesting Philosophical Idea?
Why not Angels?
What's bugging the creationists?
Summary and Conclusions.