Below Dr. Dembski replies to Dr. Barr over at First Things. Dr. Torley has also posted an excellent rebuttal at FT that I reproduce here:
Professor Barr,
With the greatest respect, you are sadly mistaken about ID, and about design arguments in general. I have a Ph.D. in philosophy, and I’ve been following the ID movement closely for a few years now. I’m neither a young-earth nor an old-earth creationist; I’m quite happy to accept common descent, although I would not be at all perturbed if it were proved false. The way I see it, there are at least five good design arguments for the existence of God. All of them are probabilistic, all of them use abductive reasoning (appealing to the best-known explanation of an observed fact), and all of them are scientifically falsifiable. As we shall see, ID design arguments are not particularly different from the others. Let’s summarize the design arguments briefly.
1. The laws of physics, and the theory underlying them, manifest an extraordinary degree of beauty, elegance, harmony, and ingenuity, from a mathematical perspective. This elegance is an unexpected bonus, even in a life-friendly cosmos such as our own. For even if the forces of nature were finely-tuned, nothing would necessitate the laws underlying them hanging together in a mathematically elegant way, which even our best scientific minds marvel at. The underlying mathematical beauty of the cosmos is extremely improbable, on the face of it, as the ugly, unaesthetic theories that could serve to underlie Nature vastly outnumber the mathematically elegant ones. But if the cosmos is the work of a Divine Mind, mathematical elegance is precisely what we would expect to find. Moreover, Mind is the only thing we know that creates beauty. See “Universe or Multiverse? A Theistic Perspective” by Robin Collins, especially part 6.
2. The constants of Nature in our universe appear to be fine-tuned for life to emerge. The odds of these constants having the values which would permit life to emerge are vanishingly small. Nor does it help to posit a multiverse which churns out many universes, of which ours happens to be the lucky one; for the multiverse would have to possess certain unique physical properties in order to be able to churn out anything at all. Once again, the odds of a multiverse possessing these properties are vanishingly low, on the face of it; but if the cosmos was designed for life, this is what we should expect. Moreover, Mind is the only thing we know that creates things according to a plan. See “The Fine-Tuning Design Argument” by Robin Collins.
3. The DNA code appears to possess certain properties which make it an ideal carrier of genetic information. It is unexpectedly robust, and extremely resilient against minor copying errors, which makes it ideal from an evolutionary perspective. Additionally, the genetic coding found in DNA is unbelievably efficient and compact. DNA information is overlapping, multi-layered and multi-dimensional; it reads both backwards and forwards. Even our best computer scientists can’t write code like this. Once again, the antecedent probability that the molecule embodying the genetic code of living organisms should possess these properties is extremely low; but if a Divine Mind wrote the original program code for DNA, we would expect it to be both efficient and resilient. Moreover, Mind is the only thing we know that can write efficient codes. See “Astonishing Complexity of DNA Demolishes Neo-Darwinism” by Alex Williams.
4. Even the simplest viable living things found on Earth contain about 250 kinds of proteins, each of which contains a large amount of highly specific information relating to their particular function. Proteins are made up of sequences of amino acids (usually at least 150); yet the vast majority of amino acid sequences that could occur are incapable of folding up properly, and hence incapable of doing anything useful. Even given billions of years, the odds of Nature generating even one amino acid sequence that can perform any kind of useful function are astronomically low, and the odds of generating a simple cell with 250 useful proteins are infinitesimal. One could hypothesize the existence of as-yet undiscovered bio-friendly laws that make life’s emergence more probable; yet there would have to be a large number of these laws, to create a “magic pathway” leading to life, and they would have to be very specific (i.e. information-rich). Once again, this is not what one would expect, unless the laws of Nature were designed for life. Moreover, Mind is the only thing we know that creates specified information. See “Intelligent Design: Required by Biological Life?” by Kalinsky, K. D.
5. Cells contain a large number of structures whose functionality depends on all their constituents being in place. In some cases, scientists can identify parts of these structures that still perform some useful function; yet the likelihood that these structures were built up one part at a time, on a step-by-step basis, appears to be vanishingly low, as most of the steps along the way would have conferred no evolutionary benefit whatsoever. For instance, the bacterial flagellum has about 30 vital parts; a biologically useful 10-part subcomponent of the flagellum has been identified, but getting from 10 to 30 is still a huge jump. There may be unknown “magic pathways” that take us there, for each and every one of these “irreducibly complex” structures; yet even the most careful examination of these structures has yielded no hints of such bounty from “Mother Nature.” One would not expect to find such “magic pathways,” unless the very warp and woof of the evolutionary process was designed by God to pave the way for the emergence of complex life. Moreover, Mind is the only thing we know that creates specified complexity. See “Irreducible Complexity Revisited” by William Dembski.
Arguments 4 and 5 are ID arguments; some might say argument 3 is, as well. Note that arguments 3, 4 and 5 do not require Deus ex machina interventions. That’s a cheap anti-ID canard. ID proponents really don’t care how God made the world; what matters is that He did it.
Note too that all of these arguments are falsifiable. Consider E8, the most elegant and intricate shape in mathematics. Some physicists are trying to build a “Theory of Everything” which incorporates this structure. If the universe is the work of a Divine Mind, I’d certainly expect it to instantiate the most beautiful possible geometry. But that expectation could be dashed, which would falsify the first argument. Likewise, skeptical physicists like Victor Stenger have argued that the universe is not as finely-tuned as we imagine, and that life could emerge in universes with constants with values utterly different from those in ours. If Stenger is right, then the second design argument is falsified. Again, DNA looks pretty optimal, as a carrier of genetic information, but if scientists manage to design a better carrier, or show that alternative, less efficient carriers would have been weeded out almost immediately, then that undermines the third argument. Likewise, a demonstration that chance, coupled with the KNOWN laws of chemistry, would have been sufficient to generate the DNA, RNA and proteins that we find in simple cells, AND bring them together in the right way to make a cell, would destroy the fourth argument. Finally, the discovery of very smooth incremental pathways which could account for “irreducibly complex” structures without the need for any unusual biochemistry or odd-looking fitness functions, would dramatically undercut the fifth argument.
Science does not have to “fail” for ID to be true. All science has to do, for ID to succeed, is reveal the antecedent improbabilities of life arising and of irreducibly complex structures emerging. ID would not be threatened by the discovery that Nature contains a hidden bias toward life, so long as this built-in bias is “surprising,” from a scientific standpoint (i.e. wholly unexpected, based on a priori considerations).
Certain readers on [the First Things] thread have expressed a dislike for creationism and/or ID, because of the evil found in the natural world. If they think evil is part of God’s created order, they should read David B. Hart’s article “Tsunami and Theodicy” . If they think that Christianity can be squared with “God-made-it-look-random theistic evolution” (as opposed to the “God-guided-it-and-you-can-see-where evolution” I espouse), then they might like to read David Anderson’s response to Dr. Denis Alexander (especially chapters 11 to 15). Finally, if they are looking for a theodicy which accounts for the evil found in the natural world, then I would warmly recommend “The End of Christianity” by Dr. William Dembski, which makes a strong case that natural evil could still be the result of sin, even in a very old, evolving world where evil pre-dates human sin. I should add that if you want to account for evil in the natural world, then like it or not, you’re going to have to invoke malevolent intelligent agents (a.k.a demons) interfering with God’s original plans, and you’ll need a Fall too. And if that freaks some readers out, they should ask themselves: “Am I letting science dictate my religious beliefs?” Once you start doing that, there’s no stopping.
There’s one teleological argument I haven’t discussed yet. The real outlier among the teleological arguments for the existence of God is St. Thomas Aquinas’ Fifth Way, which is not a design argument at all. The Fifth Way might be better described as an argument from normativity, as it takes as its starting point the simple fact that objects in the world possess causal powers, which implies that when they exercise these powers, they act as they should – in other words, despite being devoid of intelligence, they conform to norms and exhibit what philosophers call intentionality. Aquinas argues that the directedness of objects can only be explained by positing a Divine Mind. This is an argument that I find very persuasive, but it relies on certain metaphysical premises which some atheists might reject. Design arguments simply rely on mathematics and science; the metaphysics is relatively non-controversial. Probability theory, combined with abductive inference, is what takes us to God with design arguments.
Professor Barr is terrified of another Galileo case. I’m not. We’re uncovering layer upon layer of wholly unexpected complexity in life and the cosmos, whose existence we never even suspected a generation ago. And if scoffers want to call this “God-of-the-gaps” reasoning, that’s fine by me. The gaps are GROWING, NOT shrinking. But what really terrifies me is the prospect of the next generation of children being brainwashed by the “politically correct” scientific establishment to believe that the emergence of the cosmos, life and intelligence as a result of natural processes was no big surprise, and that it was bound to happen sooner or later anyway. That’s what they’re being exposed to now, in our schools. And if you ask these children ten years from now if they believe in God, they’ll look at you with an incredulous stare and utter the words of Laplace: “I have no need of that hypothesis.” Now THAT scares me.