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That phrase "specified complexity" is pretty nifty. It appears to mean whatever you want it to mean.

I was wondering about that too. As neither Anthony nor centromere have jumped on him for it I thought perhaps it was a legit term.

Or maybe it's part of the ID lexicon, coming somewhat after "kinds".


I think it's more akin to "irreducible complexity." I suppose I could have looked it up right away, but I thought it might be more productive to ask Bryan detail what he meant by "complexity" and "specification" and to provide the evidence that DNA exhibits both of these qualities and then ask him to detail how those qualities make a designer for DNA more likely. Apparently, asking for these details isn't allowed under Bryan's debate rules.

I figured that "specified complexity" would fall into one of two catagories. The first category includes things like the old creationist/ID argument that evolution violates the Second Law of Thermodynamics, a flawed argument that stems from their lack of understanding of what that Law actually says. Take a real theory, modify it to say what you want it to say (not what it really says), and then reach the conclusion you wanted to reach. The second category includes things like "irreducible complexity." These are fancy phrases for things that turn out to be devoid of any real utility on closer inspection, due to the fact that they bear little resemblance to reality. But, they sound technical and cool, so creationists eat them up, assuming that these terms have some substance.

I guessed that this was a phrase coined by either Behe or Dembski. Googling gave me: and, Bingo!, it's a phrase made up by Dembski. Just a couple highlights:

Specified complexity is an argument proposed by William Dembski and used by him in his works promoting intelligent design. According to Dembski, the concept is intended to formalize a property that singles out patterns that are both specified and complex. Dembski states that specified complexity is a reliable marker of design by an intelligent agent, a central tenet to intelligent design which Dembski argues for in opposition to modern evolutionary theory. The concept of specified complexity is widely regarded as mathematically unsound and has not been the basis for further independent work in information theory, complexity theory, or biology.


The soundness of Dembski's concept of specified complexity and the validity of arguments based on this concept are widely disputed. A frequent criticism (see Elsberry and Shallit) is that Dembski has used the terms "complexity", "information" and "improbability" interchangeably. These numbers measure properties of things of different types: Complexity measures how hard it is to describe an object (such as a bitstring), information measures how close to uniform a random probability distribution is and improbability measures how unlikely an event is given a probability distribution.

When Dembski's mathematical claims on specific complexity are interpreted to make them meaningful and conform to minimal standards of mathematical usage, they usually turn out to be false. Dembski often sidesteps these criticisms by responding that he is not "in the business of offering a strict mathematical proof for the inability of material mechanisms to generate specified complexity".[21] Yet on page 150 of No Free Lunch he claims he can prove his thesis mathematically: "In this section I will present an in-principle mathematical argument for why natural causes are incapable of generating complex specified information." Others have pointed out that a crucial calculation on page 297 of No Free Lunch is off by a factor of approximately 10^65.[22]

Dembski's calculations show how a simple smooth function cannot gain information, he therefore concludes that there must be a designer to obtain CSI. However, natural selection has a branching mapping from one to many (replication) followed by pruning mapping of the many back down to a few (selection). These increasing and reductional mappings were not modeled by Dembski. In other words, Dembski's calculations do not model birth and death. This basic flaw in his modeling renders all of Dembski's subsequent calculations and reasoning in No Free Lunch irrelevant because his basic model does not reflect reality. Since the basis of No Free Lunch relies on this flawed argument, the entire thesis of the book collapses.

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