By James Gruetzner
The intelligent design movement hypothesizes that there are some things in the natural world which cannot be explained by natural causes. These things are said to only be capable of explanation in terms of an intelligence outside of the local natural environment which has designed the system in question. This paper explains the concept of irreducible complexity as it relates to the intelligent design movement. Various areas of dispute within science are reviewed, and some of the theological issues associated with intelligent design are discussed.
1. Introduction and history
Anyone perusing the topic of faith and science will sooner or later encounter references to the Intelligent Design movement. One will soon see that the very phrase “Intelligent Design” has a number of definitions, sometimes mutually exclusive. This article will follow the definition used by many of its founders and major proponents, such as biologist Michael J. Behe of Lehigh University and mathematician and philosopher William A. Dembski of Baylor University. The website of the Discovery Institute, Center for Science and Culture, where both these academicians are Senior Fellows, brings Luther’s Small Catechism to mind as it provides this definition:
1. What is the theory of intelligent design? The theory of intelligent design holds that certain features of the universe and of living things are best explained by an intelligent cause, not an undirected process such as natural selection .
The question immediately arises asking what are some of the characteristics which something should have in order for one to conclude that it can be best explained as resulting from the direction of an intelligent cause. The focus of this article will be on living things, for which the characteristic of irreducible complexity has been proposed as an indicator of design in nature.1 Other proposed characteristics, such as the anthropic principle in cosmology are more metaphysical or philosophical in nature, and won’t be considered here.
2. Irreducible Complexity
In his book No Free Lunch, philosopher William Dembski gives the following definition of irreducible complexity:
A system performing a given basic function is irreducibly complex if it includes a set of well-matched, mutually interacting, nonarbitrarily individuated parts such that each part in the set is indispensable to maintaining the system’s basic, and therefore original, function [2, p. 285].
Examples of proposed irreducibly complex systems include such diverse phenomena as the vertebrate eye, the bombardier beetle, and the flagella of certain bacteria. The contention in each of these is that the system is composed of several separable parts, each of which would not develop under evolutionary pressure on its own, and which require all or most of the parts in order to produce a system with evolutionary advantage.2
Hypothesizing that something is irreducibly complex3 uses inductive reasoning, rather than a deductive method. It starts with observations, and infers a reasonable process which would produce those results. It is thus a forensic approach, investigating facts and developing hypotheses concerning those facts.
A forensic approach is an appropriate part of science, and has its own successes and pitfalls. A popular presentation of these methods is familiar to viewers of the CBS hit show CSI: Crime Scene Investigation. Each episode dramatizes a team of investigators examining selected evidence from a crime scene. Sometimes the evidence is incomplete or misleading; sometimes their initial hypotheses are wrong; often they need to go back to the crime scene and look for more evidence. In the end — this is television, you know — they come up with the right answer as to what produced the evidence they examine. Usually the evidence is accidentally produced at the crime scene, occasionally it is placed there by design, and at times the evidence is a result of natural or external factors such as a rainstorm.
Forensic science works similarly. In the case of biological changes, the evidence at the scene is the fossil and historical record of living things. The scientist takes the information available and constructs a theory which explains as much of the data as possible. This was the mode in which Charles Darwin was operating when he wrote On the Origin of Species . He examined some of the data at hand, and developed a hypothesis on a process (not a mechanism) which he believed would produce the observed data. In the famous example of Galapagos Island finches, he developed a hypothesis to explain why the finches on one island were different from those of another, based upon the assumption that they descended from the same ancestral population. A case for concluding that a biological feature was the result of intelligent design is made in much the same manner: data is observed which is characterized by an irreducible complexity. A scientist may then be persuaded that the feature is best explained by the process (again, not the mechanism) of intelligent design.
3. Areas of dispute
Like most scientific hypotheses, intelligent design has not been without criticism. Nor has it been without its uncritical supporters. As is often the case, the reality lies somewhere in between the claims of reactionary proponents and opponents. This paper discusses some of the implications and issues surrounding the intelligent design hypothesis, examining how it relates to a philosophy of science, to young-earth creationism, to materialism, and to William Paley’s classical theory of perceived design. The subsequent section will then briefly examine the relationship of intelligent design to Christian theism, including some critiques of the hypothesis — or of a too-heavy reliance on it — from the point of view of Christian theology.
3.1 Definitions of “science”
What we today call “science” was in the not so distant past called “natural philosophy.” It wasn’t until the nineteenth century that the present terminology became dominant. As this etymology indicates, “science” concerns things of “nature”– of matter, energy, and things which can physically be sensed or seen. It has been argued that “science” — by definition — can only concern itself with nature and with causes found in nature. Since any intelligent design hypothesis leaves open the possibility of an extranatural or supernatural cause, by definition it cannot be “science,” and must be something else.
This is really an argument of definition in the field of scientific philosophy, rather than an actual objection. It restricts in advance the application of the name “science” to certain conclusions which might arise in the investigation of the natural world. Science investigates the properties and situation in the natural world; this is its subject matter. However, the proposed objection imposes a severe a priori restriction on what the investigation of the natural world can tell us about reality. What is called “science” then is limited to being an intellectual entertainment, rather than the investigation of what the natural world can tell us about reality.
It is somewhat akin to the discredited notion that “science disproves the existence of miracles.” In fact, the opposite is the case: without science, no event can be termed a miracle. Science establishes the natural course of things. Pour water into a jar and immediately dip it out. It will still be water. If it is suddenly wine, well, something unnatural has happened. Science cannot explain the “how” of the change, but it can tell us that the change is a miracle.
In many respects, intelligent design theory’s place within the scientific enterprise is similar to that held by the search for extraterrestrial intelligence (SETI). SETI theorists have proposed a number of characteristics which might be used to indicate that a signal was produced by an intelligent life form–an intelligent designer of the signal [5,6]. SETI examines the natural world and proposes that something might be able to be inferred about the origin of certain phenomena. In response to claims that SETI is not science, various arguments have been made justifying its position within science (e.g., Fricke ). Many of these arguments can be applied mutatis mutandis to what is often called the intelligent design project.
3.2 Intelligent design and young-earth creationism
Some opponents of intelligent design bolster or ground their objection in the belief that intelligent design hypotheses are a form of young-earth creationism.4 This confusion is encouraged by many young-earth supporters, who have embraced intelligent design in the belief that it provides a scientific justification for their own beliefs. Both of these positions fail to consider the extent and the limits of an intelligent design hypothesis.
Logically, a young-earth creation neither depends upon nor mandates that any part of a young creation exhibit irreducible complexity. In other words, from a young-earth point of view, it does not matter whether or not anything appears to be irreducibly complex or not, just as it does not matter whether or not the earth and heavens appear to be billions of years old or not.
As Behe points out, “Intelligent design proponents do question whether random mutation and natural selection completely explain the deep structure of life. But they do not doubt that evolution occurred. And intelligent design itself says nothing about the religious concept of a creator.”  The key point is that, although they do not contradict it, intelligent design theories do not imply a young-earth. Hypotheses on the age of the earth and on the evidence of intelligent design do not intersect.
Intelligent design hypotheses are much more limited in scope–much more limited than some would like. Geneticist Gordon Mills of the University of Texas Medical Branch notes the limited claims. “[Intelligent] Design Theory…never postulates that all changes must be due to specific acts of design, whereas the traditional evolutionary view insists that all changes must be a consequence of chance (usually gene duplication, mutation, and natural selection).”  In other words, natural design hypotheses do not directly attack all instances of biological evolution.
3.3 Intelligent design and philosophical materialism
Objections to intelligent design hypotheses are strongest from those who support philosophical materialism. In this context, materialism is the philosophical belief that the only things with actual existence are those in the physical world and subject to investigation with the tools of nature: there is no spirit world, no God — or even gods — nothing else besides what we can physically sense or infer from our physical senses. Intelligent design is perceived as a direct attack on their philosophy, and posing a scientific (as opposed to philosophical) threat to that belief.
The main threat feared in the materialist attack appears to be theism — Christian theism in particular.5 While this fear is attractive at first face, it again does not cover the whole breadth of possibilities which a successful intelligent design argument would support. Philosophers James D. Madden and Mark Discher claim that intelligent design “would primarily constitute an argument sufficient to undermine materialism but insufficient for determining which nonmaterialist explanation of biological origins is most plausible.” 
Madden and Discher point that interventionist creationism — the theistic belief that God manipulates or creates the material world — is only one metaphysical theory which is consistent with the intelligent design hypothesis. They specifically mention two others. One is the theory that physical particles have nonphysical, mental, properties at their most basic level; this is the theory of atheistic panpsychism [11, 12]. Given this belief, a non-materialistic theory to explain intelligent design characteristics, such as irreducibly complex systems, can be constructed which would not necessarily require the existence of a deity engaged in intelligent design.
Another theory which is consistent with intelligent design is Aristotelianism, the theory that “each organism has an immaterial component, a ‘form.’ It is in virtue of its form that an organism is structured in a certain way such that it is a member of a natural kind. Irreducible complexity, so the Aristotelian might argue, could then be accounted for by the influence of the organism’s form. Since Aristotelian forms are not empirically detectable, Aristotelianism is underdetermined by any scientific research program.”  In effect, any system which is irreducibly complex could be manifesting an attribute of its underlying form; there is no logical necessity that such a form be established by God.
There are other possibilities than those enumerated by Madden and Discher, some of which do not even contradict naturalism. Several of these are variations of “cosmic zoo” hypotheses , in which life on earth is the product of or has been manipulated by extraterrestrial beings: the “intelligent designer'” is a non-human — albeit quite natural — being. This is a stock theme in science fiction literature, such as the recent movie Mission to Mars . A lesser possibility is panspermia, which is the hypothesis that the seeds for biological life-the basic DNA, so to speak — arrived from space on one or more of the multitude of meteorites which have hit the earth. A materialist form of a panspermia theory consistent with intelligent design theories would apply to those aspects of intelligent design which might have been encoded in such hypothesized seeds.
The point of mentioning this is not to argue here that any of these is more or less likely, but that it is an error to state that intelligent design provides a proof for God’s existence and action in the world. Arguably, it does not even necessitate the rejection of materialism. A conclusion that a certain biological system is the irreducibly complex product of intelligent design may provide support for theism, but it is neither necessary nor sufficient for any form of theism, be it young-earth creationism or other forms.
3.4 Paley’s perceived design
At the beginning of the nineteenth century, English philosopher and theologian William Paley published a treatise, Natural Theology . This treatise collected and expanded on the various design philosophies which were prevalent in the preceding century and which date back to the time of the Roman Empire. With the well-known example of a fine mechanical watch, Paley argued that, just as a person who examined a watch would perceive that there was a designer who had planned and created it, so would a person who examined the natural world perceive that there was a Designer who had planned and created it.
Paley’s argument is basically philosophical in nature, and it is in the realm of philosophy where major counterarguments have prevailed. David Hume especially attacked the analogical argument in his Dialogues Concerning Natural Religion . The weakness of Paley’s perceived design is that it is based upon analogy. The analogy is between a watch and the universe. The trouble with analogical arguments is that they are logically open and even tautological: the analogy holds only insofar as they are analogous.
Paley’s argument is:
1. A watch has the property of being designed.
2. The universe is perceived to be like a watch to a certain degree.
3. Therefore, the universe has the property of being designed.
The philosophical counter is to deny premise (2) by noting that, “no, the universe is very much not like a watch.” Paley’s argument, therefore, fails.
The difference between Paley’s perceived design and the intelligent design theories is quite significant. “Irreducible complexity” is not based upon an analogy, but upon the concept that certain systems are not merely incomplete, but useless, until and unless all the component parts are present. Intelligent design hypotheses are grounded in scientific investigation, in “advances in probability theory, computer science, the concept of information, molecular biology, and the philosophy of science–to name but a few.”  Aside from the mutual use of the word “design,” the concepts are very dissimilar.
A second difference is apparent when examining the consequences of the two theories. Paley and others6 tried to used observations to infer a wise and benevolent Deity. Paley saw a fine-tuned creation, with near-perfect design. Actual observations of nature showed something quite different: nature is cruel. John Stuart Mill observed, “If there are any marks of all special design in creation, one of the things most evidently designed is that a large proportion of all animals should pass their existence in tormenting and devouring other animals.” 
Modern intelligent design theorists bypass this question entirely, leaving it to philosophers and theologians. “Nature is a mixed bag. It is not William Paley’s happy world of everything in delicate harmony and balance. It is not the widely caricatured Darwinian world of nature red in tooth and claw. Nature contains evil design, jerry-built design, and exquisite design. Science needs to come to terms with design as such and not dismiss it in the name of dysteleology.” 
In other words, intelligent design deals with questions of science, not of cruelty in nature or the nature and attributes of God. These are valid issues and areas of concern, but they belong to the realm of theology and apologetics, not science. Science concerns the what and how of things, not the why.
4. Intelligent Design and Theism
4.1 Relationship to Christian fundamentalism
We have seen that “intelligent design itself says nothing about the religious concept of a creator.”  Nor is it an argument for young-earth creationism, although it is compatible with that viewpoint. It is perhaps most supportive of a theistic evolution viewpoint — that God created nature with the ability to evolve and change, but also chose at times to intervene directly in some cases. Yet this support is by no means conclusive.
Even so, many people associate the intelligent design movement with Christian fundamentalism, as a web search combining intelligent design and fundamentalist reveals. Much of this is a rhetorical technique of guilt by association, where ‘fundamentalist’ is not used neutrally, but serves as a codeword for “ignorant and stupid religious person not as smart as we are.” For example, in a recently conducted internet search, one of the first results was a link to an Times article by English biochemist Terrence Kealey. Dripping with haughty contempt, he wrote, “In reality, however, 99 per cent of ID supporters are fundamentalist Christians who believe in the literal truth of Genesis, Deep South-style. This is why ID’s hub is the Discovery Institute–which, despite its authoritative name, is a typical American palaeoconservative think-tank.” 
Given that the Discovery Institute’s Board of Directors includes people with a variety of religious beliefs (including mainline Protestant, Roman Catholic, Eastern Orthodox, Jewish, and agnostic), Kealey’s remarks can most charitably be attributed to ignorance.7Some moderate Muslims also support the concept of intelligent design. 
An accurate description would be that intelligent design proponents come from many religious traditions, and also include agnostics. These many traditions include Christian fundamentalism (in many of its varied forms), but fundamentalists are not in the forefront of the intelligent design movement. Again, the emphasis is on the scientific foundations of intelligent design, and not on intelligent design as an alternative to other approaches. “As a matter of public policy, Discovery Institute opposes any effort to mandate or require the teaching of intelligent design by school districts or state boards of education. Recognizing the potential for sharp conflict in this area, Discovery Institute believes that a curriculum that aims to provide students with an understanding of
the strengths and weaknesses of neo-Darwinian and chemical evolutionary theories (rather than teaching an alternative theory, such as intelligent design) represents a common ground approach that all reasonable citizens can agree on.” 
This is not a position which would be commonly linked with fundamentalism.
4.2 Discussion within the church
It is also apparent that intelligent design, as a movement, has arisen within Western civilization–with its own immense debt to Christianity–and that many of its spokesmen are Christians. Thus it is fair to note that, in addition to the discussion of intelligent design within science and philosophy, there is also a fairly robust discussion within Christian theology and apologetics concerning the theory.
As noted in section 3, it is clear that the ‘designer’ in intelligent design theories is not necessarily the Triune God, or even a theistic or deistic God. It is, however, compatible with Christianity, and the conclusion–or even strong inference–that a given
biological system has been intelligently designed has bearing on both natural theology and Christian apologetics.
The apologetics case is straightforward. Although intelligent design does not necessitate that there is a God who is concerned with our world, it provides evidence in support of that contention. It is another piece of evidence which suggests that there is a God and that He is involved in the world.
Natural theology is that part of theology which describes the knowledge of God drawn from nature. While Christians understand that the revelation of God found in nature is incomplete, it is also not something to be dismissed, as the scriptures tell us: “For since the creation of the world, God’s invisible qualities — his eternal power and divine nature — have been clearly seen, being understood from what has been made…” (Romans 1:20) It is a regrettable source of confusion that the term ‘natural theology’ is also used for those religious beliefs which contend that God can only be known from the revelation of nature; that is not what is meant by my use of the term.
As touched on in previous sections, intelligent design does not say much about God’s character. Modern science developed within a society imbued with the understanding of God as a lawgiver. Science arose as an attempt of man to understand the regular laws which God had laid down in His creation. To a great degree, science presumes that the natural world would operate in a consistent–not arbitrary–manner.8 For a Christian, however, intelligent design implies that there are times when God elects not to follow His own laws, and instead intervenes for His own purposes. This suggests something about the character of God: He sets up laws and enforces them, but He is willing to suspend these laws when He desires something else.
Thus intelligent design implies that, while God remains outside of His creation (transcendent) much of the time, He will occasionally break into creation in order to produce something new and marvelous. If this is the case, then the natural world helps show that it would be in God’s character to suspend His own law and transfer the guilt of sin from sinners to the Sinless, in His desire to bring sinners into fellowship with Him. “Neither circumcision nor uncircumcision means anything; what counts is a new creation.” (Galatians 6:15)
On the other hand, there are at least two reasons which some Christian theologians have noted argue against finding intelligent design in creation.
One objection from Christian theology is that the God has revealed that His creation is “good” and, therefore, complete. This has perhaps been best articulated by Calvin College physicist Howard J. Van Till, who speaks of a fully gifted creation  or a robust formational economy . He contends that God is revealed to us as perfect, and thus His creation should be perfect. “Nothing would be missing from the universe’s resources, capabilities, or potentialities that would prevent it from actualizing (assembling by the exercise of its formational capabilities) any type of physical structure (like a planet or a protein) or any type of organism that has appeared in the course of time.” 
Van Till and others point out that, in many historic instances, Christians have deviated from this principle and ended up with a God-of-the-gaps. A God-of-the-gaps proponent uses the lack of knowledge about something — for example, the cause of lightning, or the eclipse of the sun — to argue for the existence of God. In other words, God’s existence is proven by His action in doing something for which we have no other explanation. The problem is that, all too often, the mechanism is found, and it is not God acting directly (lighting, eclipse), but God acting through a natural law that He has established (atmospheric ionic charges, the shadow of the moon in orbit). While this is not directly destructive to faith, the skeptic can use a history of failed God-in-the-gaps to infer that all evidence of God — including revelation — will eventually be discovered to be just another natural process. Therefore, Christians should be extremely hesitant to proclaim that God’s actions are revealed in something that is not known at present, but may one day become known as a result of scientific investigation.
A second objection has more the nature of a warning than an outright objection. It also has more of a Lutheran flavor, and is based directly on the Gospel revelation of God’s character. It starts from the belief that God’s character is most truly and fully revealed in the life, death, and resurrection of Jesus Christ, centered on His suffering on the cross. A theology of the cross is the only true theology; any other theology is a theology of glory and must be rejected. Lutheran pastor and physicist George L. Murphy is a proponent of this view . The scriptures show that God acts in a hidden manner, without ostentation. “He was despised and rejected by men…like one from whom men hide their faces, he was despised, and we esteemed him not.” (Isaiah 53:3)
In the same manner, God’s work in His creation is hidden and not evidenced by glorious displays. God desires to remain hidden within His creation. Just as He uses the means of grace to bestow salvation, so also He uses (natural) means to bring forth life within His creation. But intelligent design specifically searches for places to reject God’s use of means. The motivation of intelligent design is thus seen as posing a danger by becoming a search for a God of glory, and therefore a rejection of the God of grace.
5. Conclusion and implications
The possibility that God has revealed Himself to man in nature through the evidence of irreducible complexity is intriguing. It can neither be dismissed out of hand in advance, nor can it be expected to yield conclusive examples of intelligent design. If well established, it would become very similar to an ongoing miracle, giving testimony to unbelievers of the power of God. If no instance can be reliably found, then faith in Christ Jesus should not be shaken. Christians can and do take positions on both sides of the issue, without threat to their faith.
Martin Luther once noted that a person’s god is whatever he looks to for good and in which he finds refuge in time of need [25, First Commandment]. There is danger that a person’s faith be placed in an intelligent design theory — or in its rejection. In either case, a person doing so is seeking refuge in human understanding. It is a matter of perspective. Intelligent design or other scientific theories are not the center of faith. Our trust needs to remain in the Gospel of the forgiveness of sins through the suffering, death, and resurrection of Christ Jesus. That is indisputably the intelligent design God has for our lives.
1. In this article, nature refers to that part of creation which is physical, as opposed to intellectual, spiritual, etc.
2. Some people are confused about evolutionary advantage, perhaps misunderstanding the slogan “survival of the fittest.” The survival of a specific trait in a reproductive population–not individuals–is postulated to occur not because that trait is better in some absolute sense, but because that trait provides some advantage for or “fits” better in a given environment.
4. Young-earth creationism is the belief that the age of the earth and the universe is on the order of 10,000 years or less.
5. Theism is the belief that a personal God involves Himself in human affairs. Contrast this with deism, in which God only manifests Himself in the natural world.
6. These are advocates of natural theology, which reasons from observations of nature to the characteristics of God. Ironically, Paley et al. are theological liberals, and would be very much opposed to what today we broadly include within theological conservatism.
7. Ironically, while the Discovery Institute’s politics would be called `conservative’ in the United States, in Europe it would be labeled `liberal’ or `classically liberal’ in orientation.
8. The causal relationship between Christian theology and the development of science (natural philosophy) is much too great of a topic to discuss in this paper.
2. William A. Dembski. No Free Lunch: Why Specified Complexity Cannot Be Purchased without Intelligence. Rowman & Littlefield, Lanham, MD, 2002.
3. William A. Dembski. The Design Inference: Eliminating Chance through Small Probabilities. Cambridge University Press, Cambridge, 1998.
4. Charles Darwin. On the Origin of Species by Means of Natural Selection, or the Preservation of Favoured Races in the Struggle for Life. ebook available at http://www.gutenberg.org/etext/1228, 1859.
5. T. L. Wilson. “The search for extraterrestrial intelligence.” Nature, 409:1110-1114, 22 February 2001.
6. H. Paul Shuch. “Optical SETI comes of age.” SPIE, 4273:128-135, 2001.
7. Arthur C. Fricke. “Philosophical perspectives on the problem of extraterrestrial signal detection.” SPIE, 4273:213-217, 2001.
8. M. J. Behe. “Design for living.” The New York Times, page A21, 7 February 2005.
9. Gordon C. Mills. “In defense of intelligent design.” Perspectives on Science and Christian Faith, 54(4):260-263, December 2002.
10. James D. Madden and Mark Discher. “What intelligent design does and does not imply.” Perspectives on Science and Christian Faith, 56(4):286-291, December 2004.
11. Thomas Nagel. Mortal Questions, chapter “Panpsychism.” Cambridge University Press, 1991 (reprint).
13. John A. Ball. “The zoo hypothesis.” Icarus, 19:347-349, 1973.
14. Brian de Palma, director. Mission to Mars. Walt Disney Home Video, 2000.
15. William Paley. Natural Theology. available online at http://www.hti.umich.edu/cgi/p/pd-modeng/pd-modeng-idx?type=HTML&rgn=TEI.2&byte=53049319, 2d. edition, 1809.
17. John Stuart Mill. Three Essays Concerning Religion: Nature. available online at http://www.la.utexas.edu/research/poltheory/mill/three/nature.html, 1874.
18. Terence Kealey. “What is…’Intelligent Design’?” Times Online, http://www.timesonline.co.uk/article/0,,1072-1407612,00.html, 18 December 2004.
19. Mustafa Akyol. “Why muslims should support intelligent design.” http://www.islamonline.net/english/Contemporary/2004/09/Article02.shtml, 14 September 2004.
20. David K. DeWolf and Seth L. Cooper. “Teaching about evolution in the public schools: A short summary of the law.” Technical Report www.discovery.org/scripts/viewDB/index.php?command=view&id=2543, The Discovery Institute Center for Science and Culture, April 2005.
21. Howard J. Van Till. The Fourth Day: What the Bible and the Heavens are telling Us about Creation. William B. Eerdmans, Grand Rapids, Michigan, 1986.
22. Howard J. Van Till. “Is the creation a ‘right stuff’ universe?” Perspectives on Science and Christian Faith, 54(4):74, December 2002.
23. George L. Murphy. The cosmos in the light of the cross. Trinity Press International, Harrisburg, Pennsylvania, 2003.
25. Martin Luther. Large Catechism. 1529.