November 9, 2014

Examining the origins debate, part 7

This is part 7 in a series exploring Gerald Rau's book Mapping the Origins Debate. For other posts in the series, click a number: 123456, 8.

Learning from each of the origins models

To help us learn from all six of the origins models, Rau points out the strengths and weaknesses of each, particularly related to how each explains all of the scientific evidence (not just the evidence that is easily adapted to the model).

Strengths of each model

Strengths of neo-Darwinian evolutionist models. The primary strengths of his group of models largely has to do with explaining gradual change and common descent. In astronomy, the idea of gradual development following the big bang, recently has been bolstered by several lines of evidence including cosmic microwave background radiation patterns. These lines of evidence point to a similar date for the beginning of the universe. Evidence from genetics indicates gradual development of species in that it points to the gradual accumulation of identical mutations in different lineages across boundaries that separate species. For example, identical genetic markers have been found in apes and humans (p157). Evidence from paleontology (fossils) provides additional support for the idea of intermediate or transitional forms.

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Of course, supporters of creationist models are least likely to recognize these lines of evidence, due to a prior commitment to the separate creation of each of the biblical "kinds." But as more and more evidence of intermediate forms and genetic similarities are found, the strictly creationist models (young earth creation and old earth creation) lose credibility.

Strengths of non-Darwinian evolutionist models. A growing number of evolutionists are coming to accept models that embrace saltational evolution (non-gradual evolutionary processes), relying on a a growing body of evidence that points to the creative potential of natural selection. They question the neo-Darwinian position that gradual change through mutations plus natural selection is sufficient to produce new species (p158). Instead, they point to evidence of times of rapid change, including ones that involved gene transfers across boundaries between species. Though such ideas of rapid change were once considered heretical among scientists, an increasing number of evolutionists are embracing them (though they are in the minority). A related (and for some a troubling) question, is how such saltational changes could have occurred without some sort of "teleological control" (p159). This, of course, opens the door to the models that embrace various forms of theistic evolution.

Strengths of the old-earth creation (OEC) model. According to Rau, the primary strength of the OEC model is how it points out difficulties with nonteleological models. One of its earliest contributions was to highlight evidence for the fine-tuning of the universe that make it suitable for life. For old-earth creationists (and others), this is evidence of supernaturalism. In response to this contention, strict evolutionists (those who hold exclusively to naturalism) have posited what is known as the "anthropic principle" (see earlier posts), which though acknowledging the the fine-tuning, denies supernatural causation.

A second line of evidence emphasized by OEC proponents is the Cambrian explosion, "which until about ten years ago was not even mentioned in textbooks" (p160). OEC supporters have long pointed to this explosion as evidence of a specific period of creation. More recently, proponents of the OEC model and of others embracing what is known as "Intelligent Design" emphasize mathematical evidence of "irreducible complexity" (explained by Rau in chapter 4)--a line of evidence typically downplayed by evolutionists.

Typical argumentation from those espousing Intelligent Design (ID)

Strengths of the young-earth creation (YEC) model. According to Rau, "It is very difficult to evaluate the contribution of young-earth creation objectively, because both the evidence and the interpretations presented by this model are so different from the majority of the scientific community." Were YEC correct, "it would require the rewriting of just about every science textbook" (p161). Given its prior commitment to the recent creation of the cosmos (about 10,000 years ago), YEC must reject any evidence for gradualism (uniformitarianism) and emphasize those fossil layers that appear to have been laid down suddenly. Though evidence for such layers is not disputed by science, little of it has made its way into lower-level science textbooks.

Weaknesses of each model

Each model has certain inherent weaknesses with respect to how it deals with the scientific evidence, particularly with respect to explaining the origin of life.

Weaknesses of the evolutionist models. According to Rau, all of the evolutionist models have a significant problem in that they claim that...
..we will ultimately be able to explain the origin of life on the basis of natural laws, possibly with some involvement of... random events that happened to occur at just the right time and place to make life possible without divine intervention or direction... The problem with this scenario is that there is no viable hypothesis of how life could have arisen; no deterministic processes have been found that would inevitably lead to life, and the probability that the complexity of life arose by chance is extremely low (p163).   
As Rau notes, the concepts of probability and chance as defined by science are not widely understood outside scientific circles (Rau helpfully explains the terms). Creationists need to be careful to understand how science uses these terms before offering critiques. However, given the complexity of life, "chance, by itself, is looking less and less probable as a way of generating the necessary complexity" (p165). Creationists, of course, emphasize this problem. Noting the evidence for massive amounts of information in the genetic code, they ask the obvious question: "How and when did all that information originate?" Answering this question is a major challenge for evolutionary models given their pre-commitment to denying any sort of supernatural involvement.

Weaknesses of the creationist models. These models, of course, accept supernatural involvement in creation, including imbuing the genetic code with massive amounts of information. However, none of the creationist models have proposed a scientific mechanism for that creation. Those who embrace directed evolution believe God could and probably did continue to interact with creation following the initial big bang--but no writer supporting this model has addressed the mechanism of this intervention. Rau sees this lack as a weakness and goes on to propose an approach to addressing it (one that includes the use of biblical testimony).

Rau also points out weaknesses that are particular to the YEC model. He notes its belief that essentially all the fossil-bearing sedimentary rock on earth was laid down during a global flood (the Noachian deluge). However, this claim lacks credibility for several reasons--Rau highlights the lack of the distribution of pollen throughout sedimentary rock layers (p169). He also notes how YEC lacks a credible explanation for the extremely rapid tectonic movement and migration/speciation that would be necessary if the model were true.

Seeing the big picture

A key problem in the ongoing origins debate is the narrow focus (due to specialization) among its participants. According to Rau, all sides need to break out of their narrow perspectives and work together to "see the big picture" (p170). All sides need to consider all the evidence, not just what fits their model. Doing so, of course, is a huge challenge given the massive amount of evidence. Adding to the problem is the reality that those who provide funding for research typically dictate what lines of research are allowed. As a result, "science is not the totally objective-dispassionate search for truth that some believe it to be" (p173). Of course, the same statement can be made about theology.

Is there then no way for the sides to come together in meaningful dialogue? Rau comments:
To work together we must examine the best evidence, examples and arguments used by the opposition, not the weakest. We must not denounce them based on their model or the underlying worldview, or focus on old arguments they have already abandoned. This requires actually reading what they write rather than looking for points to attack, participating in dialogue rather than debate, looking at the actual evidence, not secondary descriptions of it. It requires more work but is the only way to reach the desired end....
The greatest advances in origins research will likely come from those willing to take the time and effort to combine the best work from all sides of the debate, and respond thoughtfully to opponents, rather than brushing them off as worthless (pp173-174).
Next time we'll conclude this series with Rau's thoughts on the heart of the origins debate. If you'd like to do some reading about various theistic evolutionary models, you'll find some brief book reviews on GCI's website by clicking here. For a related previous post on this blog, click here.

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