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Unguided or Not? How Do Darwinian Evolutionists Define Their Theory?

An argument we are increasingly hearing from theistic evolutionists is that the “unguided” or “random” aspects of Darwinian evolution are merely “philosophical gloss” or an “add-on” promoted by new atheists who use bad philosophy. Jay Richards covered this question in his recent dialogue with Alvin Plantinga–see here, here, here, and here for the series. While many new atheists undoubtedly make poor philosophers, the “unguided” nature of Darwinian evolution is not a mere metaphysical “add on.” Rather, it’s a core part of how the theory of Darwinian evolution has been defined by its leading proponents. Unfortunately, even some eminent theistic and intelligent design-friendly philosophers appear unaware of the history and scientific development of neo-Darwinian theory.

A friend recently sent us a link to William Lane Craig’s response to Jay Richards on whether Darwinian evolution is necessarily “unguided.” Jay had written a response to Dr. Craig’s prior argument that “when the evolutionary biologist says that the mutations that lead to evolutionary development are random, the meaning of the word ‘random’ is not ‘occurring by chance.'” The conversation centered around a 2007 paper by Francisco Ayala in Proceedings of the National Academy of Sciences USA, “Darwin’s greatest discovery: Design without designer,” where Ayala wrote:

Chance is, nevertheless, an integral part of the evolutionary process. The mutations that yield the hereditary variations available to natural selection arise at random. Mutations are random or chance events because (i) they are rare exceptions to the fidelity of the process of DNA replication and because (ii) there is no way of knowing which gene will mutate in a particular cell or in a particular individual. However, the meaning of “random” that is most significant for understanding the evolutionary process is (iii) that mutations are unoriented with respect to adaptation; they occur independently of whether or not they are beneficial or harmful to the organisms. Some are beneficial, most are not, and only the beneficial ones become incorporated in the organisms through natural selection.

(Francisco J. Ayala, “Darwin’s greatest discovery: Design without designer,” Proceedings of the National Academy of Sciences USA, 104 (May 15, 2007): 8567-8573.)

Dr. Craig thinks Ayala’s descriptions of these processes are perfectly compatible with theism. Perhaps they are. The problem is that Ayala’s paper makes it clear that under the definition of Darwinian evolution, there’s a lot more that’s “random” than the fact that mutations arise without respect to the needs of the organism. In that same paper Ayala explicitly defines Darwinian evolution in undirected, non-teleological terms.

It was Darwin’s greatest accomplishment to show that the complex organization and functionality of living beings can be explained as the result of a natural process–natural selection–without any need to resort to a Creator or other external agent. … The scientific account of these events does not necessitate recourse to a preordained plan, whether imprinted from the beginning or through successive interventions by an omniscient and almighty Designer. Biological evolution differs from a painting or an artifact in that it is not the outcome of preconceived design.

(Francisco J. Ayala, “Darwin’s greatest discovery: Design without designer,” Proceedings of the National Academy of Sciences USA, 104 (May 15, 2007): 8567-8573.)

Ayala’s conclusion is clear:

The theory of evolution conveys chance and necessity jointly enmeshed in the stuff of life; randomness and determinism interlocked in a natural process that has spurted the most complex, diverse, and beautiful entities that we know of in the universe: the organisms that populate the Earth, including humans who think and love, endowed with free will and creative powers, and able to analyze the process of evolution itself that brought them into existence. This is Darwin’s fundamental discovery, that there is a process that is creative although not conscious. And this is the conceptual revolution that Darwin completed: the idea that the design of living organisms can be accounted for as the result of natural processes governed by natural laws. This is nothing if not a fundamental vision that has forever changed how mankind perceives itself and its place in the universe.

(Francisco J. Ayala, “Darwin’s greatest discovery: Design without designer,” Proceedings of the National Academy of Sciences USA, 104 (May 15, 2007): 8567-8573.)

Ayala further states, concludes that “[i]n evolution, there is no entity or person who is selecting adaptive combinations.” (emphasis added)

Under Ayala’s definition of Darwinian evolution — which is a pretty standard treatment of the topic — it would seem to rule out the possibility that the process was guided by God or any other intelligent agent, entity, or person towards a certain outcome. This directly contradicts Dr. Craig’s suggestion that Francisco Ayala’s formulation of Darwinian evolution is perfectly compatible with theism.

Indeed, as I explain in God and Evolution, a review of how mainstream biology textbooks define Darwinian evolution reveals it is defined as a “random,” “blind,” “uncaring,” “heartless,” “undirected,” “purposeless,” and “chance” process that acts “without plan” or “any goals,” where we are “not created for any special purpose or as part of any universal design,” and “a god of design and purpose is not necessary.”

This is not simply my opinion–this is a review of biology textbook definitions of neo-Darwinian theory.

Generally speaking, I find myself nearly always agreeing with Dr. Craig’s arguments. A few years ago I had the pleasure of watching Dr. Craig offer a compelling debate performance against Christopher Hitchens on “Does God Exist.” But on this issue of the nature of Darwinian theory, I find myself in a rare situation where I disagree with Dr. Craig.

Unfortunately I think Dr. Craig makes a mistake in the very first paragraph of his response to Jay:

Lest distressed readers miss the forest for the trees, we agree on the central point: that insofar as a person claims that the evidence of evolutionary biology has shown that the evolutionary process, based as it is on genetic mutations and natural selection, is undirected, purposeless, or non-teleological, he is making a claim that hopelessly outstrips the scientific evidence and so is unjustified.

Craig suggests that his disagreement with Jay is small (e.g. a tree), but actually I think it makes quite a big difference (e.g. it’s a forest). Here’s the disagreement:

  • Craig would say that the scientific evidence cannot, in principle, show that “undirected” or “purposeless” processes created life. Thus, Craig would say Christians have nothing to fear from Darwinian biology.
  • We would say that the evidence COULD show that life arose by “undirected” or “purposeless” processes, at least as far as we can tell, but it in fact DOES NOT. So we would say that Darwinian biology could in-principle challenge theism, but because the theory is empirically false, it doesn’t.

So the debate is over whether Darwinian biology could challenge theism. He thinks it can’t. We think it could. This isn’t a trivial debate: Since most biologists endorse Darwinian biology, this is a very important question.

Thus, in my opinion, our disagreement isn’t over a “tree” but rather over something as important as the “forest.” Also, our disagreement shows that the only way to defeat “unguided” evolution is on the science, by showing it’s empirically wrong. I think that’s a much sounder approach than ignoring how leading evolutionary biologists like Ayala define Darwinian theory, and then trying to convince people that Darwinism isn’t really unguided after all.


Casey Luskin

Associate Director and Senior Fellow, Center for Science and Culture
Casey Luskin is a geologist and an attorney with graduate degrees in science and law, giving him expertise in both the scientific and legal dimensions of the debate over evolution. He earned his PhD in Geology from the University of Johannesburg, and BS and MS degrees in Earth Sciences from the University of California, San Diego, where he studied evolution extensively at both the graduate and undergraduate levels. His law degree is from the University of San Diego, where he focused his studies on First Amendment law, education law, and environmental law.