FIGURE 18.6
Comparison of persistent morphological isolation in two animal forms that first arose in the Cambrian period, and similar morphological isolation in two technological systems.
The persistent morphological disparity and isolation of animal body plans is completely unexpected by neo-Darwinian, and all other gradualist, evolutionary theories, at least. Given such models of evolutionary change, theorists should expect the fossil record to exhibit forms of life that grade imperceptibly from one to another. Indeed, absent either a compelling version of the artifact hypothesis or an adequate mechanism of punctuated large-scale evolutionary change, “morphospace” should be mostly filled in. The fossil record should not display mostly morphologically disparate or separate forms of animal life.
Yet, if living systems did arise as the result of intelligent design, then such morphological isolation, and such persistent isolation over time, is just what we should expect to see—precisely because that is what we do see in the history of other intelligently designed systems (see Fig. 18.6). Indeed, experience suggests that designed objects have a functional integrity that makes the modification of some of their essential parts and their basic organization and architecture difficult or impossible. Though the Model-A has been replaced by everything from the Yugo to the Honda Accord, the automobile “body plan” with several essential functional and/or structural elements has remained unchanged from its first appearance in the late nineteenth century.
Further, despite the design of many innovative variations, automobiles have retained their “morphological distance” or structural disparity from other functionally distinct technological devices. Indeed, persistent morphological disparity in biological systems (manifested as stasis in the fossil record) has a direct parallel in our own technology. In biology, what we recognize as different organismal body plans are systems that differ fundamentally from each other in their overall organization. A crab and a starfish, for example, may exhibit some similarities in their low-level protein parts, but they differ fundamentally in their digestive and nervous systems and in the overall organization of their organs and body parts. In the same way, automobiles and airplanes may have many similar parts, even as they differ in the composition of their distinguishing parts and overall organization.
The presence of such structural disparities and isolation among complex functionally integrated systems represents another distinctive feature of the intelligently designed systems known from our own world of technology. For example, the basic technology of the CD-ROM (as employed in audio systems and computers) did not “evolve” incrementally from earlier technologies, such as magnetic media (e.g., digital tape or disc storage) or analog systems such as the once standard long-playing (LP) record. Indeed, it could not. In an analog recording, information is stored as three-dimensional microscopic grooves in a vinyl surface and is detected mechanically by a diamond stylus. This means of storing and detecting information differs fundamentally, as a system, from the digitally encoded pits storing data in the silvered surface of a CD-ROM, where information is detected optically, not mechanically, by a laser beam. The CD-ROM had to be engineered from scratch and, as a result, displays a striking structural difference and isolation from other technological devices, even those that perform roughly the same function. Although minor new features may “accrete” to its basic design architecture, a deep and impassable functional gulf separates the CD-ROM as a system from other technological systems. As biologist Michael Denton expresses it, “What is true of sentences and watches is also true of computer programs, airplane engines, and in fact of all known complex systems. Almost invariably, function is restricted to unique and fantastically improbable combinations of subsystems, tiny islands of meaning lost in an infinite sea of incoherence.”32 In fact, such structural disparity or morphological isolation constitutes a diagnostic of designed systems—that is, a feature of systems for which only one kind of cause—an intelligent cause—is known.
Acts of Mind
Studies in the history and philosophy of science have shown that to explain an event or a set of facts, scientists must typically cite a cause capable of producing that event or those facts. When scientists do not have the luxury of directly observing the cause of a particular event or effect under study, as historical scientists typically do not, they must cite a cause that is otherwise known to produce the facts in question. That means historical scientists must show that the event or facts of interest must in some way represent the expected outcome of a particular cause having acted in the past—that the event or facts should have occurred “as a matter of course.”
To many scientists, especially those steeped in the materialistic assumptions of contemporary scientific culture, the idea of intelligent design seems inherently implausible or even incoherent. Science to them involves not only observing and studying material entities and phenomena, but explaining them by reference to materialistic entities. For these scientists, it makes no sense even to consider the idea of intelligent design, with its explicit reference to the activity of a designing mind.
Yet it turns out that both the Cambrian animal forms themselves and their pattern of appearance in the fossil record exhibit precisely those features that we should expect to see if an intelligent cause had acted to produce them (see Fig. 18.7). Further, the Cambrian animal forms and their manner of appearance contradict what we should expect to find in the fossil record and in the animal world given a purely materialistic “bottom-up” process of evolution. Thus, despite its potential for disturbing the materialistic sensibilities of many scientists, it is hard logically to avoid the conclusion that the design hypothesis actually provides a better, more casually adequate explanation for key features of the Cambrian event.
When Darwin first acknowledged the problem of the Cambrian fossil record, and the small but persistent doubt it raised for him about his theory, his nemesis Louis Agassiz not only rejected his theory of evolution, but also affirmed an alternative understanding of the nature and origin of animal life. To Agassiz, the pattern of animal classification and the fossil record reinforced the idea that living forms exemplified basic “types”—ideas that had originated in the mind of a designing intelligence. Thus, he would argue that the Cambrian fossils tell of “acts of mind.”33
As noted in Chapter 1, Darwin himself acknowledged both Agassiz’s immense paleontological knowledge and the validity of the problems that Agassiz raised. Even so, his affirmation of a positive alternative to Darwin’s theory in the form a design hypothesis might well have seemed premature in the 1860s and certainly did reflect something of the prejudice of the times. But more than a century and a half later, after many failed attempts to discover—and explain away—the missing fossil ancestors, and after discoveries in molecular and developmental biology have revolutionized our understanding of the complexity of animal life, continuing to regard the Cambrian explosion as merely a niggling problem for established theory—a lone question mark or negative clue—now seems not so much cautious, as simply unresponsive to the evidence.
FIGURE 18.7
Both the Cambrian animal forms and their pattern of appearance in the fossil record exhibit distinctive features or hallmarks of designed systems—features that we should expect to see if an intelligence acted to produce them.
The animal forms that arose in the Cambrian not only did so without any clear material antecedent; they came on the scene complete with digital code, dynamically expressed integrated circuitry, and multi-layered, hierarchically organized information storage and processing systems.
In light of these marvels and the persistent pattern of the fossil record, should we now continue, as Darwin did (who knew nothing of them), to regard the Cambrian explosion as just an anomaly? Or may we now consider the features of the Cambrian event as evidence supporting another view of the origin of animal life? If so, is there now a compelling logic for considering a different kind of causal history?
In fact, there is. The
features of the Cambrian event point decisively in another direction—not to some as-yet-undiscovered materialistic process that merely mimics the powers of a designing mind, but instead to an actual intelligent cause. When we encounter objects that manifest any of the key features present in the Cambrian animals, or events that exhibit the patterns present in the Cambrian fossil record, and we know how these features and patterns arose, invariably we find that intelligent design played a causal role in their origin. Thus, when we encounter these same features in the Cambrian event, we may infer—based upon established cause-and-effect relationships and uniformitarian principles—that the same kind of cause operated in the history of life. In other words, intelligent design constitutes the best, most causally adequate explanation for the origin of information and circuitry necessary to build the Cambrian animals. It also provides the best explanation for the top-down, explosive, and discontinuous pattern of appearance of the Cambrian animals in the fossil record.
19
The Rules of Science
The argument of the previous chapter raises an obvious question. If intelligent design provides such a clear and satisfying resolution to the mystery of the Cambrian explosion, why have so many brilliant scientists missed it?
While reflecting on this question, I came across a short story by G. K. Chesterton called “The Invisible Man,” which may cast some light on it. In “The Invisible Man,” Chesterton tells the story of someone who is murdered in an apartment with only one entrance, an entrance watched by four honest men. These men insist that during their watch no one entered or left the building. A brilliant French detective investigates the case, along with his friend, a dusty little Catholic priest. They query the guards, each of whom insists that no one entered or exited the building. But then the unimpressive looking priest, Father Brown, all but forgotten in the background, pipes up to ask, “Has nobody been up and down stairs, then, since the snow began to fall?”
“Certainly not,” they assure him.
“Then I wonder what that is?” Father Brown asks, gazing at the white snow on the outside entrance stairs. Everyone turns to find a “stringy pattern of grey footprints” there.
“God!” one of them cries, “An invisible man!”
After asking a few more questions, Father Brown quickly unravels the mystery. “When those four quite honest men said that no man had gone into the Mansions, they did not really mean that no man had gone into them,” Father Brown explains to his detective friend. “They meant no man whom they could suspect of being your man. A man did go into the house and did come out of it, but they never noticed him.”
“An invisible man?”
“A mentally invisible man,” the priest explains.
What does a mentally invisible man look like?
“He is dressed rather handsomely in red, blue and gold,” the priest explains, “and in this striking, and even showy, costume he entered Himylaya Mansions [the name of the apartment complex] under eight human eyes; he killed … [the murder victim] in cold blood, and came down into the street again carrying the dead body… . You have not noticed such a man as this.”
At that moment, he reaches out and puts his hand on “an ordinary passing postman,” one who had almost slipped by them unnoticed.
“Nobody ever notices postmen somehow,” Father Brown muses. “Yet they have passions like other men, and even carry large bags where a small corpse can be stowed quite easily.”1
The passing postman, of course, is the murderer. He walked up and down the stairs under the four men’s noses, but because of their mental blinders telling them whom to consider and whom to ignore, they overlooked the postman entirely.
The theme is a favorite of detective-story authors: the obvious possibility missed by the experts, because their assumptions prevent them from considering what might otherwise seem to be an obvious possibility. Could something like that be at work in the investigation of the Cambrian explosion? Could evolutionary biologists and paleontologists be wearing a set of mental blinders that keeps them from considering a possible explanation of the Cambrian mystery?
Odd as it may seem, that is exactly what has been going on in the investigation of the Cambrian explosion. In this case, however, those wearing the mental blinders have elevated an unwillingness to consider certain explanations to a principle of scientific method. That principle is called “methodological naturalism” or “methodological materialism.” Methodological naturalism asserts that to qualify as scientific, a theory must explain phenomena and events in nature—even events such as the origin of the universe and life or phenomena such as human consciousness—by reference to strictly material causes. According to this principle, scientists may not invoke the activity of a mind or, as one philosopher of science puts it, any “creative intelligence.”2
To see how adherence to this principle has prevented scientists from considering a possibly true (even “causally adequate”) explanation for the Cambrian explosion, let’s revisit the case reported in Chapter 11 of Richard Sternberg (see Fig. 19.1), the evolutionary biologist at the Smithsonian’s National Museum of Natural History. After Sternberg published my article arguing for intelligent design as the best explanation of the Cambrian information explosion in the technical journal Proceedings of the Biological Society of Washington,3 he suffered professional retribution at the hands of Smithsonian administrators.4 The Biological Society of Washington, the governing body that oversees the publication of the journal that Sternberg then edited, also issued a public statement repudiating his decision.5 Its statement did not, however, cite any factual errors in the article or seek to rebut it. Further, the president of the society, Smithsonian zoologist Roy McDiarmid, wrote Sternberg privately and told him that he (McDiarmid) had reviewed the file containing the peer-review reports and had found everything to be in order.6
What, then, had Sternberg done to deserve public rebuke?
Sternberg published a paper that violated a presumed rule of science: methodological naturalism. Without saying it in so many words, the Biological Society made crystal clear that this was the crucial issue. When it distanced itself from Sternberg and the review essay, it did not invite a scientific refutation of the article, as if the problem had been a misrepresentation or misinterpretation of the evidence. Instead, it attempted to settle the issue by releasing a policy statement. As a writer in the Wall Street Journal reported at the time, “The Biological Society of Washington released a vaguely ecclesiastical statement regretting its association with the article. It did not address its arguments but denied its orthodoxy, citing a resolution of the American Association for the Advancement of Science that defined ID [the theory of intelligent design] as, by its very nature, unscientific.”7
FIGURE 19.1
Richard Sternberg. Courtesy Laszlo Bencze.
The Biological Society of Washington “deemed the paper inappropriate for the pages of the Proceedings.”8 The Society attempted to justify this claim, first, on thin procedural grounds, claiming that a paper about the origin of animal body plans represented a “departure” from its more typical concern with issues of animal classification. Second, and more tellingly, it cited the policy statement of the American Association for the Advancement of Science (AAAS) “calling upon its members to understand the nature of science” and to recognize “the inappropriateness of ‘intelligent design theory’ as subject matter for science education.”9 Setting aside the obvious point that my paper was written not as a curricular manifesto but as an evidence-based scientific argument, the AAAS statement affirmed an implicitly and strictly materialistic understanding of the nature of science. It did so to disqualify intelligent design from consideration—not only in science education, but in science itself.
The Sternberg case—like numerous others in which the academic freedom of scientists advocating intelligent design has been abridged10—goes a long way to answering the question of why so many otherwise brilliant and knowledgeable scientists have overlooked such a seemin
gly obvious possible answer to the Cambrian conundrum. As in Chesterton’s story about the invisible postman, they have accepted a self-imposed limitation on the hypotheses they are willing to consider. These scientists think they are doing their duty to science. Yet if researchers refuse as a matter of principle to consider the design hypothesis, they will obviously miss any evidence that happens to support it. And the cultural pressure within biology to avoid considering the intelligent design hypothesis has long been nontrivial. Francis Crick, for example, famously admonished biologists to “constantly keep in mind that what they see was not designed, but rather evolved.”11 In 1997, in an article in the New York Review of Books, Harvard geneticist Richard Lewontin made explicit a similar commitment to a strictly materialistic explanation—whatever the evidence might seem to indicate. As he explained in a now often quoted passage:
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 counterintuitive, no matter how mystifying to the uninitiated. Moreover, that materialism is absolute, for we cannot allow a Divine Foot in the door.12
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