“The fundamental difficulty (familiar from the central mystery of Cartesian dualism, how mental substance could interact with physical substance) is rather that by appealing to the intentions of an agent which, being immaterial, cannot put Its intentions into action by physical means, they fail to explain at all.” - Susan Haack on supernatural explanations, from Defending Science Within Reason
A scheme or system of ideas and statements held as an explanation or account of a group of facts or phenomena; a hypothesis that has been confirmed or established by observation or experiment, and is propounded or accepted as accounting for the known facts; a statement of what are known to be the general laws, principles, or causes of something known or observed. - Oxford English Dictionary definition of theory
Intelligent Design is the belief that certain biological systems are too complex to have arisen out of natural evolutionary processes, and must therefore be the result of an intelligent designer, an entity that proponents of I.D. neglect to describe. Without any account of how or when the Intelligenct Designer designs there is no epistemic difference between the proposed Intelligent Designer and an immaterial supernatural agent. Without any coherent account of the designer we have no way to know what to expect from such a designer. For example, I can immediately think of a number of questions, left unanswered by I.D., that would need to be addressed before the belief could be considered a theory able to explain data and predict new data.
When does the Designer step in? At what point does evolution stop and design begin? How do we distinguish between intentional design and non intentional design? How does the Designer design? How do we know what the intentions of the designer are?
In its attempt to be designated as a theory, Intelligent Design fails to meet the three basic components of scientific theory: 1. a theory makes predictions, 2. a theory can be falsified, and 3. a theory explains observed phenomena.
- Intelligent Design makes no predictions:
In science a theory not only accounts for previously observed phenomena, but also yields testable hypothesis that predict new observations.
I.D. can not make any predictions, because it does not have any means to generate testable hypothesis. The nature of the designer is unknown to us, so we have no idea of what kind of design to expect in nature.
- Intelligent Design is not falsifiable
Intelligent design can not be tested. If you begin with the assumption that the world exhibits design, then any observed phenomena can be made to fit this hypothesis. It is a question begging form of inquiry.
- Intelligent Design has no explanatory power:
Given that we assume I.D. to be true what exactly does it tell us about the natural world? Frankly, nothing. I.D. provides no explanation of any set of observed phenomena, and it certainly does not explain more or better than evolution. For example, Why does a bat have the same underlying bone structure in its wing that a human has in its hand? Why is the embryological development of species so similar? Why do women experience pain in child birth?
What’s more, intelligent design does not even give an account of phenomena that it claims to observe! Why do irreducibly complex organs exist? How is it that natural processes can not account for irreducible complexity? Why is specified complexity unique to intelligent design?
Irreducible complex biological systems are, as defined my Michael Behe, “composed of several well matched interacting parts that contribute to the basic function, wherein the removal of any parts causes the system to cease functioning.”
Notice that Behe has created a tautology. Any system that is missing one of its parts is by definition non-functional. I will return to this in a moment.
Behe gives as an example of an irreducibly complexity a mousetrap which is composed of several parts, of which if any of the parts are removed it will no longer be able to serve its function of catching mice. This is a terribly flawed example. It does not take much imagination in order to create scenarios in which the mousetrap loses parts and is still able to catch mice. For example, remove the base of a mousetrap, and you will still be able to catch mice. For more detailed critiques of the mousetrap example see the Resources section.
What about examples in which a removal of a part does indeed cause the system to lose its function? This is where the tautology comes in. A system that loses a part may indeed not be able to serve the function it originally performed, but that does not mean that it is not functional in some other sense. As an example, consider a pair of scissors. If you were to remove one of the blades of the scissors you would be left with a single blade which would not be able perform its function of cutting paper in the sense that scissors cut paper, but that single blade would be able to serve other functions such as cutting an apple in the manner that a knife would. This demonstrates that although something may be irreducibly complex, it does not necessarily mean that removal of any of its parts renders it non-functional.
Behe also proposes several biological systems as being irreducibly complex, such as cilia, flagella, and the blood clotting cascade. In these examples Behe believes that there is no means of accounting for the development of these systems by evolutionary mechanisms. This is an argument from ignorance and personal incredulity. Because there is no current explanation Behe assumes there will never be an explanation, and because Behe is unable to conceive of an explanation he believes that an explanation can not be conceived of.
Not only is Behe wrong about there being conceived explanations of mechanisms to account for these systems (see Kenneth Miller’s essay on the flagellum in the Resources section) but he is wrong in assuming that there is not an explanation for these systems, since some of his examples have been explained!( see Doolittle’s explanation of blood clotting in the Resources)
William Dembski proposes “An event exhibits specified complexity if it is contingent and therefore not necessary; if it is complex and therefore not readily repeatable by chance; and if it is specified in the sense of exhibiting an independently given pattern.” If some phenomena can be identified as having specified complexity and is irreducibly complex, we can then infer that it was intelligently designed.
What does this mean? Basically, it means that a highly unlikely event can not be the result of random chance. Fine, but evolution does not posit that any biological system is the result of random chance. Evolution is the result of chance (variation) being acted on by order (selection) in the direction of greater fitness. This is a process of cumulative elimination. Given enough iterations the highly unlikely becomes successively more probable.
Richard Dawkins has given a clever refutation of the argument from improbability (See Resources Section – Evolution of Improved Fitness.) The articles in the Essays Critical of Specified Complexity section of the Resources give more technical and thorough critiques of Dembski.
Law of Conservation of Information:
Dembski also claims that information cannot be created by either natural processes or chance, so there is a law of conservation of information. This law of conservation is an indicator of the existence of the Intelligent Designer, and Dembski asserts that he has given rigorous mathematical proof of the Designer's existence ... I here pause to let the reader consider the magnitude of that claim.
Dembski has taken a standard creationist argument, that evolution violates the second law of thermodynamics, and dressed it up as a mathematical proof. To understand this consider information to be order - Dembski is saying that natural processes can not generate order. The quick response to this is that in an open system entropy can decrease locally as long as entropy increases elsewhere. This works in the other direction as well, as entropy often increases, causing information to be lost as disorder increases. (See Vic Stenger's PDF essay for more on this.)
The fundamental flaws of Dembski are thus
1.He is right in recognizing specified complexity, but wrong in attributing it to intelligent design
2.He is mistaken in his understanding of evolutionary mechanism
3. He has invented a law that does not exist
Everything considered, I.D. is nothing more than William Paley’s watchmaker argument, with a mousetrap and flagellum substituted for watch and eyes, and specified complexity as a mathematical formulation of the argument from personal incredulity. It is an argument from ignorance, with a Designer being penciled in to fill the gaps in our knowledge. It is nothing more than empty criticism of evolutionary theory, and it can not be seen as a rival theory because it offers no rival explanations.
Encylopedia Entries on I.D.
Websites Supporting I.D.
Websites Critical of I.D.
Published Material on Biochemical evolution.
Science Organizations and Individuals Critical of I.D.
Web Forum Discussion of I.D.
Essays Supporting Specified Complexity
Essays Critical of Specified Complexity
http://www.talkorigins.org/faqs/fitness/ - Evolution of Improved Fitness, not directly a response to I.D. but refutes the argument of improbability
http://home.mira.net/~reynella/debate/informat.htm - deals with Information theory and related ID & creationist claims
Essays Supporting Irreducible Complexity
http://www.arn.org/authors/behe.html - Michael Behe’s response to critics
Essays Critical of Irreducible Complexity
http://www.millerandlevine.com/km/evol/design2/article.html - Kenneth Miller’s essay on flagellum
http://www.bostonreview.net/br22.1/doolittle.html – Doolittle’s essay on blood clotting
Essays about the I.D. movement
http://www.csicop.org/doubtandabout/id/ - Shows parallels between I.D. and creationism
http://www.talkreason.org/articles/Stealth.pdf - Stenger's PDF article on I.D. as creationism in disguise
http://www.iep.utm.edu/d/design.htm - Details the various forms of the design argument and criticisms of
Books on I.D.
The Design Revolution
Darwin's Black Box
Evolution: A Theory in Crisis
No Free Lunch
Why Intelligent Design Fails
God, the Devil, and Darwin
The Tower of Babble
Intelligent Design Creationism and its Critics