Jump directly to the Content
Jump directly to the content
ArticleComments [1]
Signature in the Cell: DNA and the Evidence for Intelligent Design
Signature in the Cell: DNA and the Evidence for Intelligent Design
Stephen C. Meyer
HarperOne, 2010
624 pp., 19.99

Buy Now

Robert Bishop and Robert O’Connor


Doubting the Signature

Stephen Meyer’s case for intelligent design.

All Christians affirm design because the entire universe is the creative work of God. However, believers differ over how to discern design, as well as the appropriate characterization of that design, whether primarily engineering or artistic. Intelligent design (ID) advocates adopt an engineering picture of design, a perspective playing a crucial role in their argument that design is empirically detectable in specific biological phenomena.

In his recent books, Signature in the Cell: DNA and the Evidence for Intelligent Design (SC), and Darwin's Doubt: The Explosive Origin of Animal Life and the Case for Intelligent Design (DD), Stephen C. Meyer, director of the Center for Science and Culture at the Discovery Institute of Seattle, articulates the case for design in its mature form. Although SC focuses on the origin of life and DD on the Cambrian explosion, Meyer's argument for ID takes the same form in both books and largely focuses on the intricacies of cells and DNA. Therefore, our attention largely will be on SC.[1] Of course the origin of life is an area of scientific research that presents a tremendous challenge to science. Meyer's response is to offer intelligent design as providing the best explanation for the extraordinary complexity and functionality embedded in DNA.

Meyer presents what he describes as "a rigorous case for intelligent design as an inference to the best explanation." He insists that an appeal to intelligent agency provides a better explanation for the exceedingly complex, albeit functionally specific structure of DNA and the nucleus of the cell. He has long championed this more modest, somewhat chastened line of reasoning, favoring ID for its explanatory excellence. Meyer compellingly articulates the probabilistic case for intelligent design: although material processes could explain these biological phenomena, and we may yet come up with just such an account, at present, the better account is provided by appeal to an intelligent agent. One strength of this claim, then, lies in its relatively modest ambitions.

Articulating the case as an inference to the best explanation serves well to highlight that Meyer's argument turns on both the case against the causal adequacy of fully natural processes as well as on the positive case favoring intelligent agency. ID has long suffered under the misconception that it engages in crude god-of-the-gaps reasoning or presents a simplistic argument from ignorance. Meyer deftly dispatches these common lines of objection. He does so by explicitly comparing the leading materialist origins-of-life accounts with the explanatory power of intelligent agency, an analysis which focuses readers' attention on the central decision point: At present, reason reveals of intelligent design to be a better explanation for the complexity of the functionally specific structure at the very heart of the biological world compared to explanations citing natural processes alone. This sets up "Premise One" of a two-premise, summary argument: "Despite a thorough search, no material causes have been discovered that demonstrate the power to produce large amounts of specified information."

"Premise Two" focuses on the competing hypothesis: "Intelligent causes have demonstrated the power to produce large amounts of specified information." What, precisely, does Meyer mean by "intelligence" in premise two? "By intelligent design I mean 'the deliberate choice of a conscious, intelligent agent or person to effect a particular outcome, end, or objective.' Clearly, intelligent agents, by their powers of choice, can make a causal difference in the outcome of events." The upshot is that reasonable assessment of the comparative strengths of each side of the ledger shows that the explanation appealing to intelligent agency trumps the promise of any currently conceivable natural process. Meyer concludes that "[i]ntelligent design constitutes the best, most causally adequate, explanation for the information in the cell."

In a head-to-head competition, Meyer contends, appeal to intelligent agency wins out primarily based on Charles Lyell's "Uniformitarian principle" which insists that the laws and principles at work in the universe in the past are the very laws and principles at work at present (this same principle figures prominently in Charles Darwin's work on evolution). We have no assurance that strictly natural processes have ever produced the kind of complex, functionally specific phenomena evident in the nucleus of the cell. Yet we do know that intelligent agency, in the person of human agents, does even now produce such functionally specific phenomena. Hence, Lyell's principle gives the nod to the latter hypothesis.

This comparative line of reasoning, the crucial move in the argument, does rest, however, on some underlying assumptions. First, as we have mentioned, the argument presupposes an engineering picture of design. This is particularly evident in Meyer's treating the nucleus of the cell as an information-processing system (i.e., DNA stores programming instructions like a hard drive; RNA reads these instructions; protein factories process DNA instructions). The inference that intelligent agency is the cause of DNA is largely based on our experience of human-designed information processing systems like computers and cell phones. Meyer draws liberally upon this metaphor (likewise in DD).

Nevertheless, talk of "genetic codes" and "information processing" with respect to the origin of life or the nucleus can be very limiting if not misleading. Taken literally, such descriptions suggest something like stored codes that are read and implemented by processors, like computers, which are rigidly deterministic processing systems. But, a deterministic information processing system is less effective or reliable in comparison with a teleological or goal-directed system. There is a clear difference between a nucleus functioning deterministically and one that functions reliably. The more steps there are to a deterministic program the more opportunities for unanticipated obstacles to render it unreliable (roughly, the human DNA "code" would be the length of tens of thousands of Meyer's books). Given the length of time over which developmental processes stretch, or the length of time over which self-replicating molecules must have formed in a pre-biotic environment, the abstracted notions of programs and processing seem inadequate to capture the exquisite precision and reliability of these processes. For example, teleology is more effective and reliable as a picture of how the nucleus' processes work so well over such extended periods of time in the face of myriad contingencies. The nucleus as a goal-oriented system appears to be able to flexibly function to produce its protein products under a wide variety of circumstances that a deterministic set of instructions wouldn't be able to accomplish with the same degree of reliability. Similarly, the more basic self-replicating molecular processes sought by origins of life researchers would also be goal-oriented. So in comparison with the limitations of the information processing metaphor, there is a powerful motivation for why so many biologists have continued using teleological vocabulary and explanations in genetics.

Shifting to a teleological view should be a welcome move for Meyer as it seems to lead naturally to his strongest point—that DNA performs a very specific function—but it comes at a cost. The information-processing picture gives us a number of intuitions that make it natural to pick out the highly specific functions that Meyer favors. In fact, Meyer appeals to the more muted teleological language of function, rather than that of goal or purpose, allowing him to cast the argument in the objective language of science. Biologists agree: The structure of DNA, however contingent, serves well to produce a functional outcome. There is nothing subjective in this. In spite of the complexity inherent in the coding regions of DNA, the specific arrangement "hits a functional target." That is, from among the vast array of possibilities, a DNA sequence that renders possible or enhances the life of an organism betokens the intentional activity of intelligent agency. Within the information processing picture, Meyer identifies precise functional targets for DNA, but there is a great deal of room for human interpretation, here, rather than an objective appeal to data. Within the context of the "life sciences," the function seems obvious: these phenomena exist for the production and promotion of life. This is what these biological phenomena do. But, can one assign a function, an intended role, to a natural phenomenon without first supposing that the broader context has a specific function? To speak of the function of particular phenomena is already to have provided an answer to this global question in favor of design.

It is indisputable that DNA works—it produces life. It is equally indisputable that the specific sequences are exceedingly improbable and that only a very small subset advances the interests of an organism. Therefore, echoing St. Thomas, ID insists: "Now whatever lacks intelligence cannot move towards an end, unless it be directed by some being endowed with knowledge and intelligence; as the arrow is shot to its mark by the archer." But, even though the archer hits this bulls-eye, why suppose that, and not some other, must have been the intended target? Thus while purporting to offer objective, scientific grounds for design detection, Meyer's ID argument retains this objectionable feature of classical teleological arguments. Inherent in the notion of a functional outcome is the presumption that life constitutes a distinguished outcome. An objective observer will realize that, if life is the goal, then that arrangement, however improbable, functions magnificently. If some other outcome were the goal, however—say the more modest goal of replication—then that outcome would have no particular value. Even though selfish gene theories have faded, a strong case still can be made on biological grounds that living organisms are a byproduct of replication in particular environments rather than the goal. Since life has value—to us—we naturally insist that any means conducive to life has distinctive value. But that's an interpretation we supply. Functional sequences do not, as Meyer maintains, "constitute an independent pattern or target"; rather, they constitute a productive means to an outcome in which we are all personally invested. ID's "functional finesse" fails to avoid the inherent interpretive nature of this underlying assumption.

Second, Meyer's comparative analysis assumes that natural processes and intelligent agency are mutually exclusive explanatory rivals. This assumption reflects an all too common dichotomy in both Christian and materialist circles that has its roots in the deistic-mechanistic picture of the world fashionable from the early 18th century forward: events in creation are brought about either by God's direct, unmediated intervention, or arise as the result of natural processes with no divine influence whatsoever. Evolutionary creationists, in contrast, argue that mechanisms such as mutation and natural selection are not, in fact, "wholly blind and undirected," so there is an alternative to the strict dichotomy. Meyer doesn't so much object to the manner by which "theistic evolution" accounts for the development and diversity of life as to its undetectability. ID is all about the signature, supposedly empirically evident in the cell, which demonstratively establishes the activity of agency. On the evolutionary creationist account, the work is signed using invisible ink.

A third assumption of Meyer's comparative argument is evident in the second prong, namely that intelligent agency has special causal powers. "A vast amount of human experience shows that intelligent agents have unique causal powers that purely material processes lack," he writes. Specifically, an agent cause possesses "self-conscious mind in possession of thoughts, will and intentions," the central components that do the explanatory work vis-à-vis those complex, functionally specific biological phenomena in question. If material processes lack such causal powers, then intelligent agency cannot be material. The analysis assumes that this present, adequate cause—mind—is fundamentally immaterial.

Two salient observations about this assumption: First, Meyer offers very little substantive support for mind having unique causal properties inasmuch as it is immaterial. Any way you look at it, what support might be available must certainly be regarded as philosophical rather than scientific. At least on this side of the ledger, ID looks more like philosophy than science.

Second, when Meyer claims that "[o]nly persons have such minds and only minds of this kind can create complex specified information," he appears guilty of begging the very question at hand. Biologists discover that, "[i]n virtue of their specific arrangements, the bases in coding regions of DNA and RNA and the amino acids in proteins enable these molecules to perform biological functions" and wonder how this might have happened. Mind, Meyer points out "now stands as the only cause known to be capable of producing" such phenomena. From this it follows that "there is only one known cause." But this phrase, "only one known cause," is crucially ambiguous. It might mean that, among all the possible causes, there is only one that we have good reason to believe is capable of producing specified complexity. This point, however, poses (could there be others?) rather than answers the question.

In contrast, Meyer stealthily uses this phrase to suggest that, among all the causes, we know that only one is capable of producing specified complexity, shifting an argument based on the epistemic limits of our knowledge to one based on the ontological limits of reality. "Logically," Meyer rightly insists, "one can infer the past existence of a cause from its effect, when the cause is known to be necessary to produce the effect in question." This would constitute a deductive proof of that account. But Meyer overreaches when he goes on to say, "If there are no other known causes—if there is only one known cause—of a given effect, then the presence of the effect points unambiguously back to the (uniquely adequate) cause." For this deductive line of reasoning to go through, "only one known cause" must be read as a gloss on "no other known causes." But this can only mean that, in fact, we have positive knowledge that no other causes are adequate. Only then would it follow that the single cause would be necessary to produce that effect. This exclusivity claim has the effect of rendering an argument of otherwise modest pretensions into exactly the sort of eliminative deduction that Dembski formulated in terms of his explanatory filter. In the end, it turns out that the mature ID argument remains true to its roots.

As a final thought, reflect on the difference between the designing of a director of an artistic performance and that of a hands-on engineer manufacturing a product. A good director guides and works through the independent personalities, talents, and skills of actors to achieve the goals of the performance. For someone familiar with the director watching the play, the "fingerprints" of the director are clearly visible. To someone unfamiliar with the director, unwilling to make unwarranted assumptions as to her desires, beliefs, goals, or values, the director's "signature" will not be evident. Creation as an artistic performance would have this same ambiguity for those who are acquainted with God and those who are not so acquainted. This is a biblical ambiguity familiar to Christians. With its preference for an engineering picture of design, this is an ambiguity that ID cannot abide.

Both SC and DD are worthwhile reads. By recounting Meyer's own journey, these books should lay to rest much of the ad hominem reaction to ID. Also, by explicitly presenting the argument as an inference to the best explanation, these books serve well to focus attention on the philosophical, as well as the scientific, side of the ledger. Their strengths are in rendering transparent the extent to which ID's argument depends on the plausibility of this alternative proposal. As is evident in Meyer's formulation, at its core, the theory of design offers a theory of mind, a not unexpected outcome from a philosopher.

1. Ralph Stearly, "Review Essay: The Cambrian Explosion: How Much Bang for the Buck?" Perspectives on Science and Christian Faith vol. 65, no. 4 (2013), pp. 245-257 contains good discussion of Myer's treatment of the Cambrian explosion. See also biologos.org/blog/the-grand-synthesis-reviewing-darwins-doubt-robert-bishop-part-1.

Robert Bishop is John and Madeleine McIntyre Endowed Professor of Philosophy and History of Science at Wheaton College. Robert O'Connor is associate professor of philosophy at Wheaton College.

Most ReadMost Shared