Let's look at the way Intelligent Design Creationists describe their attempt to be scientific. This is from a recent post by that well-known scientist,1 Casy Luskin, on Eovlution News & Views (sic) [Does Intelligent Design Deserve Academic Freedom?]. In that post, Luskin lists four criteria proving that ID is a genuine scientific theory.
It's the first point on the list that I want to discuss. The link takes you to a brief description of how Intelligent Design Creationism uses the scientific method to prove that gods played a role in the history of life. Here's how it works ...
Basic Intelligent Design:The hypothesis is reasonable; if gods really designed biological structures then we should be able to find evidence of that intervention.
The ways that intelligent agents act can be observed in the natural world and described. When intelligent agents act, it is observed that they produce high levels of "complex-specified information" (CSI). CSI is basically a scenario which is unlikely to happen (making it complex), and conforms to a pattern (making it specified). Language and machines are good examples of things with much CSI. From our understanding of the world, high levels of CSI are always the product of intelligent design.
If an object in the natural world was designed, then we should be able to examine that object and find the same high levels of CSI in the natural world as we find in human-designed objects.
We can examine biological structures to test if high CSI exists. When we look at natural objects in biology, we find many machine-like structures which are specified, because they have a particular arrangement of parts which is necessary for them to function, and complex because they have an unlikely arrangement of many interacting parts. These biological machines are "irreducibly complex," for any change in the nature or arrangement of these parts would destroy their function. Irreducibly complex structures cannot be built up through an alternative theory, such as Darwinian evolution, because Darwinian evolution requires that a biological structure be functional along every small-step of its evolution. "Reverse engineering" of these structures shows that they cease to function if changed even slightly.
Because they exhibit high levels of CSI, a quality known to be produced only by intelligent design, and because there is no other known mechanism to explain the origin of these "irreducibly complex" biological structures, we conclude that they were intelligently designed.
The logic fails in the "Experiment" step. When setting up a dichotomy, it is essential to eliminate one possibility before assuming that the other must be correct. In this case, the entire scheme relies on proving that irreducibly complex structures could not possibly have arisen by natural means (i.e. evolution). The conclusion is that "... because there is no other known mechanism to explain the origin of these "irreducibly complex" biological structures, we conclude that they were intelligently designed."
But that's not true. There are many different ways for irreducibly complex structures to arise by natural means. Michael Behe understood this when he wrote Darwin's Black Box in 1996. He says,
Even if a system is irreducibly complex (and thus cannot have been produced directly), however, one cannot definitively rule out the possibility of an indirect, circuitous route. (p. 40)In other words, irreducibly complex CAN arise by naturalistic processes if the pathway to their evolution is indirect. What this means is that you cannot conclude that an irreducibly complex structure leads directly to the conclusion that
In 2002, Michael Behe changed the definition of irreducible complexity [see Irreducible Complexity: The Challenge to the Darwinian Evolutionary Explanations of many Biochemical Structures]. He now describes it as ...
An irreducibly complex evolutionary pathway is one that contains one or more unselected steps (that is, one or more necessary-but-unselected mutations). The degree of irreducible complexity is the number of unselected steps in the pathway. (A Response to Critics of Darwin’s Black Box, by Michael Behe, PCID, Volume 1.1, January February March, 2002; iscid.org/)This is very interesting. The new definition specifies that the pathway to an irreducibly complex system must contain a step that is necessary but cannot have arisen by natural selection. The onus is now on Intelligent Design Creationists to prove that the creation of an irreducibly complex system requires a step that cannot possibly be due to natural selection (or random genetic drift?). It is not sufficient to just recognize a potential irreducibly complex system, you also have to describe all possible pathways to its formation and show that in all cases at least one step is evolutionarily impossible.
I don't know of a single example of such an irreducibly complex system. I can think of several examples where we aren't sure of the evolutionary pathway but in all cases we can at least speculate on how the system could have arisen by natural means. Perhaps the creationists reading this blog post can point me to a case where creationists have proved that no such pathways are possible?
I conclude that Intelligent Design Creationism is science but it's bad science because their conclusion does not follow from the evidence, nor the logic.