What about evolution? My friend recently asked during a conversation about the existence of God.
What about it?
The term is used pretty vaguely in pop culture, so let’s define it.
I take it that “Evolution” basically refers to two driving ideas. The first idea is Common Descent, the doctrine that all species on earth share a common ancestor (proposed by Darwin in “Origin of Species“). However, there are prominent evolutionary biologists, such as Ford Doolittle and Paul Davies (start at 9:00—H/T William Dembski), who strongly question or earnestly reject Common Descent, but maintain instead that there has been descent with modification. So strict Common Descent need not be affirmed by someone for him to be accepted by the evolutionary community as a true evolutionist.
Before I go on to the next idea, I want to make a quick note here. I know of no significant origin-of-species view that outright denies that descent with some amount of modification ever occurs. The furthest away from mainstream evolutionary theory one can possibly get is Young Earth Creationism. But even YEC needs to account for present-day biodiversity in light of the number of animals that could have physically fit within the dimensions of Noah’s ark. Most of their models actually have modifications occurring more rapidly than mainstream evolutionary models, as there hasn’t been much time between the Flood and the present day for the biodiversity we observe to have developed. However, the Young Earth Creationists usually argue that while evolution can occur within “kinds” (usually understood as phyla, though biological classifications are constantly in flux), it cannot occur across their bounds. Often they argue that evolution can isolate traits (think of dog breeding), but can’t ever go in reverse—you can’t take a population of poodles or pugs and breed them back up into dingos or wolves.
My point here is that while full-blown Common Descent is not seen as necessary to evolution, mere descent with modification is not seen as sufficient.
Evolution’s next idea concerns the mechanism by which modifications occur. Previously it was something like Natural Selection working in tandem with genetic mutation. If you went to public school, you know the story about how this is supposed to work. But evolutionary theory nowadays is far more complex than that. My point here is that there isn’t actually any one specific mechanism or type of mechanism that is seen as absolutely essential to evolution. In fact, the whole point of science is to be progressive. Scientists are constantly in dialogue. So the denial that Natural Selection in tandem with genetic mutation is sufficient to account for biodiversity does not place one outside the bounds of evolutionary orthodoxy (since few if any evolutionists hold to that anymore). Moreover questioning or even denying any given tenant of the Modern Synthesis does not put one under anathema from the community either; it’s an expected mechanism for scientific progress!
And once again, I know of no significant origin-of-species view that outright denies that any of the mechanisms ever proposed by evolutionists to account for modifications ever have any impact on genetics. Even Young Earth Creationists often adopt mechanisms such as Natural Selection or other ideas in the Modern Synthesis as good working explanations of certain types of changes in populations. No one accounts for every little variation in species by saying “God did it!” and pretending that that’s the whole story.
Whether or not those skeptical about the sufficiency of the mechanisms proposed thus far to account for the differences in species are accepted as evolutionists hinges on just one simple thing.
So if neither of the two driving ideas behind evolution are essential to the theory, what is? If one can question Common Descent and the Modern Synthesis and still be an evolutionist, what one thing must one affirm in order to have a chance at being accepted by the evolutionary community, and whose denial results in exclusion? Philip E. Johnson argues in his books that it’s the philosophical presupposition of Naturalism [Edit: Alvin Plantinga just came out with a book making a similar case, called “Where the Conflict Really Lies: Science, Religion, and Naturalism“]. Naturalism is the belief that nothing other than the natural world exists. So rocks exist on this view, but souls do not. The various breeds of dogs exist, dinosaurs existed, and physical mechanisms like Natural Selection may exist, but supernatural entities like angels, numbers, Plato’s forms, and God could not. This presumption drives evolutionists to try to figure out a purely physical explanation for biodiversity. And so long as one maintains this approach, he can be accepted by the evolutionary community. The moment someone considers any supernatural explanation, he’s expelled (there was even a documentary about it). In the time since Johnson’s work, the evolutionist community has actually become explicit about this very thing, with Daniel Dennett actually literally saying that we have to presuppose Naturalism at all costs—supernatural explanations of phenomena are not even admitted into the pool of live options, not even considered, not even taken seriously. They are precluded from discussion.
Our willingness to accept scientific claims that are against common sense is the key to an understanding of the real struggle between science and the supernatural. We take the side of science in spite of the patent absurdity of some of its constructs, in spite of its failure to fulfill many of its extravagant promises of health and life, in spite of the tolerance of the scientific community for unsubstantiated just-so stories, because we have a prior commitment, a commitment to materialism. It is not that the methods and institutions of science somehow compel us to accept a material explanation of the phenomenal world, but, on the contrary, that we are forced by our a priori adherence to material causes to create an apparatus of investigation and a set of concepts that produce material explanations, no matter how counter-intuitive, no matter how mystifying to the uninitiated. Moreover, that materialism is absolute, for we cannot allow a Divine Foot in the door. The eminent Kant scholar Lewis Beck used to say that anyone who could believe in God could believe in anything. To appeal to an omnipotent deity is to allow that at any moment the regularities of nature may be ruptured, that miracles may happen.
Is the presumption of Naturalism justified? The mere fact that such a question can be asked implies that Naturalism should not be blindly presupposed. If you were trying to investigate a phenomenon, would you want to consider gaseous causes but ignore solid causes? Or would you admit electromagnetic causes into the discussion but ridicule the scientist who proposes that perhaps you should consider potential gravitational influences? No. And neither should we assume that causation is always merely physical and impersonal.
The debate on Naturalism in the philosophical literature is very much alive (see this recent piece, published by the New York Times, in which Timothy Williamson, the Wykeham Professor of Logic at Oxford University and an unabashed atheist, argues against Naturalism), and this attitude that Naturalism is just a given wouldn’t go unchallenged for one second in an undergraduate philosophy classroom. You can’t just go around assuming controversial philosophical positions without argument and evidence, refusing to even admit opposing views into the discussion. That’s not science, it’s faith.
If you confuse Darwinism with unguided Darwinism, a confusion Dennett makes and Dawkins encourages, you will see science and religion as in conflict at this point (See Ruse, The Evolution-Creation Struggle 2005).
Manifestations of this confusion: the conflict raging over Intelligent Design; the National Association of Biology Teachers: until 1997 that organization stated as part of its official position that “the-diversity of life on earth is the outcome of evolution: an unsupervised, impersonal, unpredictable and natural process.
This confusion between Darwinism and unguided Darwinism is a crucial cause of the continuing debate. Darwinism, the scientific theory, is compatible with theism and theistic religion; unguided Darwinism, a consequence of naturalism, is incompatible with theism, but isn’t entailed by the scientific theory. It is instead a metaphysical or theological add-on.
So how do I answer objections to theism from evolution? Frankly, whether species evolved from a common ancestor has nothing to do with whether God exists. And the mechanism by which this alleged evolution takes place is not an account of the origin origin of life from non-living matter. Nor is it an account of the coming into being of the universe. So theism seems untouched by the theory of evolution.
As a Christian then, what do I make of evolution? Well, there are non-heretical, historical, and actively defended interpretations of the Biblical creation accounts that are compatible with the theory of Common Descent. In fact, William Lane Craig readily points out in his debates that as early as the third century, St. Augustine believed in a kind of theistic evolution. Augustine wrote in his commentary on Genesis about how God imbued creation with certain potencies that would unravel over time across successive generations—something he seemed to believe he got out of the book from pure textual exegesis.
And that was 1500 years before Darwin.
So any Christians today who entertain Natural Selection, Genetic Drift, or another evolutionary idea aren’t necessarily revising or compromising their faith to fit with the scientific evidence. Rather it seems that the essentials of the Christian faith have always had room in them to allow believing philosophers and scientists to follow the evidence where it leads on many of the issues pertaining to the origin of species.
However, while I truly believe that Christians are free to follow the scientific evidence wherever it leads, I also happen to think that there are some very serious scientific challenges to the doctrine of Common Descent (or anything remotely resembling a “Tree of Life” account of the origin of species). In addition to various biochemical, informational, cellular, mathematical, and other challenges to Common Descent (some of which, like Specified Complexity and Irreducible Complexity, I would like to treat in another post), two stand out as fairly straightforward yet powerful arguments for Uncommon Descent. These tend to be very well put by William Lane Craig, and can be found in his debate with Christopher Hitchens, as well as in various episodes of Dr. Craig’s Defender’s podcast.
The first of these challenges concerns the fossil record. Every couple of years or so, a so-called “missing link” such as Tiktaalik, Archaeopteryx, or Australopithecus Sediba, is found and sensationalized in the media (there was even a book about this cultural cycle, “Icons of Evolution”, which was made into a movie). But the thing is, in order for Common Descent to be true, there would have to be millions of transitional life forms. Think of all the transitional forms that would have to have existed just for a whale and a bat to share a common ancestor. Not to mention a giraffe and an iguana, or an anteater and a toucan. The gaps in the fossil record are not such that they can be bridged by just one fossil find of one in-between looking life form. If Common Descent were true, we would expect to have transitional fossils that are just as common as the others—it would be a very fluid, slow-morphing chain of fossils like an MC Escher painting, instead of the hurry-up-and-wait pattern we see in the fossil record. This was actually responsible for Darwin’s biggest hesitation with his own theory and it still causes doubts (cf. the Discovery Institute’s treatment of the Cambrian Explosion).
But not only are there no transitional forms where we’d expect to find millions, there are more forms where we’d expect to find fewer. If Common Descent were true, the further back you go in the fossil record, the fewer forms you would find—forms from which modern species have since branched. But instead of finding fewer, we actually find more that have become extinct (some estimate that up to 99.9% of species are now extinct, including taxa all the way up to the phyla level). The fossil record indicates attrition rather than evolution.
The second challenge facing Common Descent is simply its uncanny unlikeliness. John D. Barrow and Frank J. Tipler in their book “The Anthropic Cosmological Principle” (Oxford University Press) list 10 steps in the course of the evolution of the human genome, each of which is so improbable that before it would occur, the Sun would cease to be a main sequence star and thereby incinerated the Earth. They calculate the probability of the evolution of the human genome to be somewhere between 1 in 4 to the 180th power to the 110,000th power and 4 to the 360th to the 110,000th power. It is simply unfathomably improbable. Dr. Craig argues somewhat rhetorically that therefore, if evolution did occur, it could be considered a miracle, and therefore evidence for the existence of God and His superintendence of the process of biological evolution.
So while I think Christian orthodoxy is broad enough to allow Believers to think freely concerning the various aspects of evolutionary theory, the doctrine of Common Descent is suspect even among evolutionists, demonstrably mathematically unlikely, and doesn’t accord with the fossil record; the various mechanisms posited to account for genetic changes are all under active revision and so do not necessarily demand a high degree of credence; and the presumption of Naturalism is utterly gratuitous. For these and other reasons, I am skeptical of the explanatory power, explanatory scope, and motivation of evolution relative to other accounts of biodiversity that may admit descent with modification but do involve special creation (especially of humans), and don’t really involve evolution across kinds (probably phyla). I wouldn’t be surprised to witness a revolution in which it is more or less abandoned or significantly reassessed by the mainstream as a scientific paradigm sometime in the next 50 years. I guess that makes me a freethinking skeptic.
Evolution is unproved and unprovable, we believe it because the only alternative is special creation, which is unthinkable.
-Sir Arthur Keith, foreward to the 100th
Anniversary Edition of “Origin of Species”