Today’s post comes to us courtesy of David MacMillan, a former young-Earth creationist who is now a skilled and avid writer on the creationist movement. David, who holds a B.S. in Physics from the University of North Alabama, is well known for his comments on the Ham/Nye debate, which were published by the Huffington Post.
The article below was originally published by Panda’s Thumb and is the fifth in an eight-part series, which can be found here in its entirety. David offers a profound look at the young-Earth creationist movement, specifically with respect to how they approach evolutionary theory. I have asked to republish and interact with a few select articles, which are most relevant to discussions on this blog, but I highly recommend that you read through the entire series.
My primary aim on this page has been to elucidate how geologists reconstruct Earth history through historical scientific methods—formulating hypotheses from collected geological data and making predictions about what kind of corroboratory evidence might exist. Biologists do the same with respect to the history of life and its diversification through time, but David writes in his introduction to the series:
Creationists don’t see it the same way. Creationists artificially classify medicine, genetic research, and agriculture as “operational science,” and believe that those disciplines function in a different way than research in evolutionary biology. They understand the theory of evolution, along with mainstream geology and a variety of other disciplines, as a philosophical construct created for the express purpose of explaining life on Earth apart from divine intervention. Thus, they approach the concept of evolution from a defensive position; they believe it represents an attack on all religious faith.
I remember well just how effective this portrayal of evolution can be. It becomes impossible to discuss the topic critically in the context of science, because ultimately it determines the validity of one’s faith. The same is true when a particular reading of the Bible commits one to a firm stance on the age of the Earth. How can we honestly discuss geological evidence for Earth’s antiquity if it is regarded as an attack on biblical authority? These sorts of closely held, philosophical labels awarded to modern biology and geology allow creationism to thrive, even in an educated society.
Below, David discusses the perceived ad hoc nature of evolution. It is vital to the success of creationism that evolutionary theory not be constructed from tested hypotheses, but rather through retrospective fitting of data to an anti-theistic philosophy. I believe his comments are also relevant to critiques from so-called ‘Flood geology’, as we saw last week with respect to Milankovitch theory and orbital tuning. Any opportunity to depict circular reasoning in the historical sciences is a victory point for young-Earth creationism.
Similarly, David explains the YEC’s aversion to “flux” in scientific knowledge. If scientists shift their views, even minor details of a strong and successful theory, it exposes their weakness and warrants doubt. In this manner, YEC’s bring to scientific literature the same expectations as they do to the Bible: either it conveys truth unblemished and immutable, or it deserves our unreserved skepticism. Since the very nature of science is to refute and refine (else why would we call it research?), YEC’s feel justified in cherry-picking data to support their views and selectively build a quasi-scientific alternative.
Evolution of Evolution
by David Macmillan
Most creationists believe that the theory of evolution was developed out of an ideological commitment to explaining life apart from God. Explanations of the history of evolutionary theory often point out personal struggles in the lives of prominent scientists – Darwin most often, of course – in support of this belief. “Secular scientists wanted a way of explaining a world that didn’t require God, so they invented this ridiculous theory.” To creationists, this foundation offers an easy way of dismissing all the theoretical and observational bases of evolution. If evolution is just wishful thinking born of anti-theistic extremism, then all the “evidence” is reduced to ad hoc speculation.
Because of this misconception, creationists rarely understand the actual history of how geology, paleontology, and biology built upon each other to provide us with our understanding of the world. Mainstream geology emerged significantly ahead of Darwin’s work; many early geologists were Christians. Studying the distribution of rock layers around the globe allowed geologists to construct a complete geologic column and begin appreciating the incredible amount of time the column represents. Moreover, the regular progression of extinct species fossilized throughout the geologic column had been well-catalogued.
However, creationism requires that the development of evolutionary theory be ad hoc, driven by presupposition rather than by observation. As a result, they often assert that the geologic column doesn’t actually exist: that it’s cobbled together from bits and pieces around the world and that the layers aren’t actually consistent. It is true that there are few places in the world where all layers of the column (the Hadean and Archean and Proterozoic and Cambrian and Devonian and Permian and Triassic and Cretaceous and Paleocene and Miocene and Pleistocene and Holocene) are visible simultaneously, but this fact does not prevent geologists from identifying them. The layers of the geologic column are identified relative to each other using clear and consistent markers which function the same way no matter where you are in the world. Constructing and identifying the components of the geologic column is not the random guesswork creationism makes it out to be.
In the creationist worldview, the ideas proposed by Darwin came from a desire to explain the existence of life apart from God. They believe all “evolutionary science” came out of this particular worldview. But that is simply not the case. Darwin was not setting out to explain life apart from divine creation; he was discovering the mechanism behind the already well-established progression of life on Earth. Naturalists already understood that life had existed for millions of years at the very least; they already knew that the geologic record showed innumerable species living and flourishing and going extinct all one after another. Creationists like to frame the story as though Darwin invented the theory of common descent and then looked for evidence to fit it, when in fact his theory explained the evidence that already existed.
The idea that evolution is ideologically driven obscures its very straightforward history giving creationists an excuse to believe the development of evolutionary theory has been entirely ad hoc. This belief often manifests in accusations of circular reasoning, like the infamous, “You use the fossils to date the rocks, and then you use the rocks to date the fossils!”
In reality, of course, the established order of the geologic column had already placed stringent constraints on the design of the emerging evolutionary tree. The geological column is not just a bunch of fuzzy layers identified on the basis of the fossils discovered in them. Rather, each layer has specific properties which can identify its place in the complete column regardless of where it is in the world. The placement and distribution of fossil species within this column was already well-understood prior to the formulation of Darwin’s theory. Yet creationists insist, based on their preconceptions about the atheistic basis of evolutionary science that the tree is fictitious and is thus completely arbitrary. To creationists, the placement of fossils within the tree of life is haphazard; creatures are just shoved in wherever they might fit, with no constraints whatsoever.
Creationists will make use of any evidence they can find that seems to support their beliefs about the ad hoc development of the evolutionary tree. They will go to great lengths in discussing the slightest revisions or alterations to the tree. Any change, however slight, is taken to mean that the whole tree is arbitrary. They will hunt down obscure speculations from fringe scientists suggesting changes to the evolutionary tree, just so they can support their belief that the tree is constantly in flux. Even the most tentative suggestions of a different interpretation of the evidence will be seized, quoted, and re-quoted.
This misconception comes from a lack of understanding of how the scientific community functions. With hundreds of thousands of research scientists in the United States alone and over a million journal articles published worldwide each year, new hypotheses are constantly being proposed. But just because something shows up in a research journal doesn’t make it part of the scientific consensus. Ideas enter the realm of established science only when the initially proposed hypothesis is confirmed by subsequent research and discovery. All the major facets of common descent have been challenged numerous times, but they have remained constant within the scientific community for well over a century.
Creationists with formal training in the research sciences may be more familiar with this process, but laypeople – especially laypeople with existing skepticism toward science – will be harder to reach. Either way, the best approach is usually to start from the ground up, showing that the great age of the geologic column was well-established long before evolutionary theory emerged and that the fossil record isn’t nearly as malleable as they typically assume it to be.
Often, creationists will point to what seem like large shifts in the dating of fossils as proof that evolutionary theory is simply adapted to fit the evidence rather than making any consistent predictions. Admittedly, a change of 1-2 million years seems huge. But in comparison to the 4.5 billion year lifespan of Earth, it’s not so big. A shift of 2 million years in a 4.5 billion year history is like changing the time of a weekly meeting by four and a half minutes.
The idea of an arbitrary evolutionary tree produces two major objections from creationists. The first objection is that if evolution can adapt to match new evidence, it must not be very certain about anything. This argument is easily addressed by pointing out that there are limits to what evidence evolution can adapt to. Numerous discoveries would invalidate evolution: the famed Precambrian rabbit, the existence of completely unique morphologies with no evolutionary precursors, or any sort of true chimaera with body parts from unrelated species.
The other objection is purely philosophical and much more difficult to address. Creationists equate science’s dependence on the explanatory power of evolutionary theory with their dependence on doctrine and dogma in religion. Because they feel that religious truth must be static and unchanging, they deride evolutionary theory as “not trustworthy” simply because it can change to accommodate new evidence. They demand an authoritarian source of Absolute Truth which will not change or adapt.
Absolute certainty may be a comforting foundation in the sphere of religious dogma, but science doesn’t work that way. In fact, it can’t work that way; science is predicated on the supposition (the real underlying “assumption”) that ideas must constantly change and adapt to reflect new evidence so that we can continue to better predict processes in the world around us. The truths obtained in science are based in experience, trial, and error; the truths people seek through religion are based in revelation, faith, and trust.
Obviously, the scientific model of evolutionary common descent does not make any claims about morality (though this has not prevented many people, scientists and nonscientists alike, from using evolution or pseudo-evolutionary ideas as the justification for certain ethical or moral claims). Ideally, it would be possible to simply explain that evolution makes no necessarily or intrinsic moral judgments, but many creationists will insist that it does. This misconception is entirely separate and will be addressed further later.