13 May 2013

A theologian speaks on evolution – profundity does not ensue

It's perhaps not particularly well known that the theologian William Lane Craig is what biologist Larry Moran would call an IDiot – an advocate of Intelligent Design Creationism. In fact, he's a fellow at the ironically named Discovery Institute, along with a litany of other theologians, lawyers, and lots of other people who aren't, golly I dunno, biologists. He took a crack at debating Fransisco Ayala, who is notable for being both a biologist and an evangelical Christian (and a darling of the John Templeton Foundation). I didn't watch the debate because, well, I don't give a shit what a theologian thinks about biology. But sometimes (well... lots of times) they make such stupid remarks that I can't resist the urge for rebuke.

Which brings me to my recent visit to Reasonablefaith.org, Craig's website. In a recent "Question of the Week" segment, he's asked to clarify his view of evolution. He doesn't specifically mention Intelligent Design, but he lays his cards on the table pretty clearly:
I am not yet convinced that the mechanisms posited by the current evolutionary paradigm are adequate to explain the biological diversity that we observe today.
This should be interesting!
 You might think that if we could show that random mutation and natural selection could explain, say, how a bat and a whale evolved from a common ancestor, that would certainly show the power of these mechanisms. Think again! A bat and a whale are both mammals, which is just one of the groups of the phylum Vertebrates. Even the evolution of a bat and a whale from a common ancestor is an utter triviality compared to the vast range of the animal kingdom. Such a demonstration would do nothing to explain, for example, how a bat and a sea urchin evolved from a common ancestor, not to speak of a bat and a sponge. This represents an extrapolation of gargantuan proportions. Indeed, it represents an enormous leap of faith in the efficacy of the Darwinian mechanisms.
Actually, all it requires is a study of molecular genetics, which acts as a virtual mirror-image of the fossil record in showing the evolutionary relationship of animals. This produces the well-known phylogenetic tree of life, which shows precisely how animals evolved from common ancestors dating back hundreds of millions of years, including how bacteria, jellyfish and mammals all evolved along different lines.
So, I ask, where is the evidence for the extraordinary extrapolation the current paradigm involves? Michael Behe says that “the evidence for common descent seems compelling,” but “. . . except at life’s periphery the evidence for a pivotal role for random mutations is terrible.” Now if he’s wrong about this, then what is the evidence? I’m genuinely open to it. But what is it? When I, as an objective observer, look at the evidence, it seems to me that we haven’t been shown any good reason to think that the neo-Darwinian mechanisms are sufficient to explain the evolution of the extraordinary diversity of life that we see on this planet during the time available.
What Craig is saying is that even if evolutionary theory explains tons and tons of stuff, there's still lots of stuff it hasn't explained. Which is, of course, quite true! But the fact that Craig thinks this is a a boon for his theology just betrays his ignorance of how science actually works.

Science is not in the business of proving things. Instead, science accumulates evidence that explains known facts. A theory, like evolution, makes falsifiable predictions – not necessarily about past events (since they already happened, obviously), but about what we will discover. Kenneth Miller did a great video about one example that could have falsified evolution: the fusion of Chromosome-2. Perhaps a better-known and simpler example is that if we ever found human remains in the Cambrian sediment layers, evolution would be falsified.

But like most theories, evolutionary theory is incomplete. A great deal remains to be understood, and like a proper theologian Craig pounces on such gaps as places to insert his God, and charges that those of us who think evolution will probably fill in those gaps as having "faith in Darwinian mechanisms".

However, Craig overlooks the fact that any theory which competes with evolution must not only be falsifiable (ID is not, since you can always claim after the fact that God would design something just-so regardless of what it looks like), but it must account for everything for which the theory of evolution already accounts. And man, that is a ton of stuff. Evolution elegantly explains so much that it is the unifying theory of all modern biology and sits atop a veritable mountain of supporting evidence from the fossil record, molecular biology, homologies, genetics... the works. The evidence is so overwhelming and the facts explained so innumerable that we're justified in our confidence that evolution will most likely be able to fill in those gaps. That's a provisional assumption based on an abundance of evidence – no faith required.

So sure, it's certainly possible that evolution isn't true; perhaps some other yet-unknown theory both accounts for that which evolution already explains and accounts for that which evolution cannot yet explain. But Craig, like most IDiots, insists that in order to be accepted as true evolution must absolutely and thoroughly explain every possibly detail of biology throughout all of history and disprove the possibility of supernatural intervention. That's why he's a theologian and not a biologist – biologists usually have to understand how science works.


Speaking of divine intervention, it should come as no surprise that Craig's view of life includes precisely such a magical mechanism that by definition cannot make falsifiable predictions:
It seems to me that so-called progressive creationism fits the evidence quite nicely. Progressive creationism suggests that God intervenes periodically to bring about miraculously new forms of life and then allows evolutionary change to take place with respect to those life forms. But as for grand evolutionary change, this would not take place by the mechanisms of natural selection and mutation undirected by God. Rather we would need miraculous interventions of God in the process of biological evolution to bring about broad evolutionary change.
It's the old macro-vs.-micro evolution canard in a slightly less flagrantly idiotic disguise. But one has to wonder: Craig and others like him spend so much time extolling the elegance with which the universe is designed by God, so why, then, does God need "miraculous interventions" at all? Why couldn't he have just designed the universe to work without his intervention? 



p.s. – It occurred to me that this could actually be a great way to make a falsifiable prediction using Intelligent Design. Craig asserts that a certain level of diversity and complexity is allowed within the parameters of biological evolution, but that others require a miraculous intervention. So, ID 'theorists' could pinpoint precisely the point along the continuum of complexity in which the mechanisms of mutation and adaptation are no longer sufficient, then predict the moments when there was a dramatic change in complexity – i.e., the spontaneous emergence of a new species. If ID is true, this would help us find and identify new species.


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