Darwin Prosecuted: Review of Johnson's Darwin on Trial
Phillip Johnson is a professor at the University of California's prestigious Boalt Hall School of Law, and until the publication of Darwin on Trial was unknown as an evolution-basher. This book certainly establishes his credentials, however, and we will have Phillip Johnson to kick us around for a long time.
Darwin on Trial is an antievolution book, not a "scientific creationism" book. It complements the anti-evolutionism of the scientific creationists, and provides fuel for those who want to get evolution out of school classrooms. As such, it is important to get the word out as to why the book fails to prove that evolution as a scientific idea is on the skids. Also, Johnson comes from a major university and writes smoothly. As a result, his book has attracted a lot of attention, reportedly selling 40,000 hard-back copies during its first months on the market and now published in a second edition.
Like many conservative Christians, Johnson is concerned with the implications of evolution. Although he states in his book that theistic evolution (evolution that is God-directed) is possible, he doubts it. He is not a young-earth creationist, and in fact, is almost contemptuous of their point of view. He accepts that the earth is old, but rejects evolution, thus he is perhaps describable as an old-earth creationist. His concern with evolution is primarily religious: if evolution by natural selection (Darwinism) really happened, then it is not possible for life to have purpose and for the universe and Earth to have been designed by an omnipotent, personal God. He feels that life would have no meaning, and moral and ethical systems would have no foundation. Thus his goal in Darwin on Trial is to demonstrate that Darwinian natural selection is impossible; therefore evolution didn't take place; therefore his theological views are preserved. He stresses that Darwinism is inherently an atheistic, naturalistic philosophy.
Out of His ElementLet me stress that my objections to Darwin on Trial are not because its author lacks a Ph.D. in science. Science is not a secret activity that can be performed or understood only by priests in white coats — I've argued long and hard to try to make science explicable to nonscientists, and to demystify science as a way of knowing. But if one wishes to step out of one's area of expertise, scientist or nonscientist, it behooves one to make a careful study of the new area, and carefully weigh one's pronouncements. If I were to critique the newest developments on astrophysics, or medieval art history, or patent law, I would have to first acquaint myself with not only the fundamentals of physics, art history, or law, but also astrophysics, medieval art history, or patent law. Similarly, it behooves Johnson to study not only science, but that particular and complicated science known as evolution.
Johnson has grasped the general picture of evolutionary biology, and even some of the details, but he lacks the deep understanding that is required to make the criticisms he makes. A deep understanding of a field comes from careful study of relevant literature, including primary sources, and communication with specialists in the field. Indeed, Darwinism has been critiqued by evolutionary biologists, but there is a clear difference in quality and nuance between their criticisms and those parroted by Johnson. Perhaps this is because he got most of his information from a suspect source: the criticisms of evolution he offers are immediately recognizable as originating with the "scientific" creationists, (although Johnson disdains young-earth creationism, and speaks disparagingly of Biblical literalism.)
So Johnson includes the usual "gaps in the fossil record," "natural selection is a tautology," "there are no transitional fossils," "mutations are harmful," "natural selection is not creative," "microevolution does not explain macroevolution," "natural selection only produces variation within the kind," and the vertebrate eye and the argument from design, just as in any standard Institute for Creation Research (ICR) tract. Those of you who are up on creationist literature will be unsurprised to hear that Johnson even tells the tired old Colin Patterson/ American Museum of Natural History story, as an example of the "conspiracy" of scientists to "protect" Darwinism from criticism (See Reports 12(4):14-15.)
And this, frankly, is another reason why this book needs to be coped with, and not ignored. In many ways, it is a slick repackaging of scientific creationist materials, though far more sophisticated, and as a result, it holds more potential for harm. It has already been presented to one school board that I know of, as supporting "evidence" for how "arguments against evolution" should be included in the science curriculum. This, of course, is just another variant of the familiar creationist "equal time" argument. Creationist organizations from the Institute for Creation Research, to the Bible-Science Association, to Access Research Network (formerly known as Students for Origins Research) have promoted Johnson's book in various ways. Even though his views differ from theirs in important ways, "an enemy of my enemy is my friend," in the words of the Arab proverb.
In addition to creationist sources, Johnson quotes extensively from the secondary scientific literature, citing works by well-respected authors such as Gould, Futuyma, Dawkins, and others. Now, most of those cited are quite competent scientists and historians and even leaders in the field, but the works Johnson cites are usually those written for laypersons, such as Gould's Natural History columns. A casual reader would necessarily miss a great deal of the detail and nuance of the arguments, though perhaps acquiring an understanding of the broad sweep of contemporary evolutionary science.
As a result of his reliance on creationist sources, Johnson makes a lot of flat-out mistakes. Archaeopteryx is not mostly bird; the British Museum did not prevent the inspection of the Piltdown fossils; Zuckerman studied pre-1970 Australopithecines, so his comments on early human evolution are essentially irrelevant; most mutations are not harmful. But mostly the problems in his book reflect subtle misunderstanding of how science works — and knowing or unknowing misstatements of theory in evolutionary biology.
Johnsonian science assumes that something that is not currently fully understood is perhaps un-understandable. He concludes, for example, that the Cambrian fossil explosion, the origin of the first replicating molecule, and the evolution of whales or bats are "difficult problem(s)" for evolution, as if the fact that we don't know all the details of evolution somehow proves evolution didn't take place.
This ignores the consilience factor: the vast amount of detail from natural history that is compatible (only) with the idea that evolution actually took place. If we don't know every link in the fossil phylogeny of bats, why would this make us give up on the idea of evolution, when so many other sources of data support it? We have evidence that evolution occurred from comparative anatomy, geology, biogeography, biochemistry, astronomy — all shouting that change has taken place during the history of the universe. We can predict from comparative anatomy the fossil sequence tetrapod-reptile-mammal before we even look at the rocks. This entire monument is not about to be disassembled because we don't know exactly how bats evolved from primitive insectivores. Consilience is a phenomenon that creationists seem to have great difficulty with, so they ignore it. So does Johnson.
For someone who writes so extensively about fossils, he has remarkably little understanding of what paleontologists do, as shown by his treatment of the legged and footed fossil whale, Basilosaurus. In his notes at the end of the book (which provide illuminating glimpses into his mind-set) he states his skepticism that the legs and feet really belong to the specimen: "The article states that 'Limb and foot bones described here were all found in direct association with articulated skeletons of Basilosaurus isis and undoubtedly represent this species.' Although I accept the authors' description for purposes of this chapter, I confess that expressions like 'found in direct association with' and 'undoubtedly' whet my curiosity. Is it certain that Basilosaurus had shrunken hind limbs, or is it only certain that fossil foot bones were found reasonably close to Basilosaurus skeletons?" Amazing! "Found in direct association" is a term of art in archaeology and paleontology referring not only to proximity but to context (position, geological features, evidence of disturbance or intrusion, etc.) The phrase doesn't mean, "we think in an offhand manner that maybe these bones go together," but Johnson seems unaware of this. How can someone criticize the fossil record and have so little understanding of what paleontologists do? In addition, to criticize an interpretation of a specific fossil, one should know the comparative anatomy involved. The discoverers of Basilosaurus fortunately are skilled anatomists able to tell whether a set of fossil leg and foot bones did or did not articulate with the body as a whole.
Perhaps his greatest misunderstanding of evolution is his expectation of what a "transitional form" should be like. His goal, of course, is to discredit his version of Darwinism, which stresses slow, gradual evolution. (Johnson sometimes means Darwinism, and sometimes means Neo-Darwinism, but that is another issue.) Like the ICR's Duane Gish, Johnson will not accept evolution unless a lineage can be recreated showing every individual specimen from A to Z. If mammals arose from reptiles, for example (which technically, they didn't, but from a tetrapod common ancestor), then to "prove" this, evolutionists would have to show them a fossil that is 25% mammal and 75% reptile, then one that is 50:50, and one that is 25% reptile and 75% reptile — and then kindly fill in the gaps, please. What great confidence this shows in the fossil record! Futuyma (1982:191) puts it best, "The creationist argument that if evolution were true we should have an abundance of intermediate fossils is built by exaggerating the richness of paleontological collections, by denying the transitional series that exist, and by distorting, or misunderstanding, the genetical theory of evolution."
The way Darwin expected the fossil record to look is irrelevant to modern evolutionary theory; Darwin died over a hundred years ago. We can reasonably expect theory to change in 100 years. To quote Futuyma (p. 191) again, "The supposition that evolution proceeds very slowly and gradually, and so should leave thousands of fossil intermediates of any species in its wake, has not been part of evolutionary theory for more than thirty years." But Johnson flogs the gradualist horse because it serves his purpose to discredit evolution by natural selection.
Modern evolutionists, on the other hand, are more concerned with tracing the pattern of evolution, rather than tracing a specific lineage down to the gnat's eyelash. The pattern of evolution is more likely to be shown across a broad series of lineages within an evolving taxon. Transitional structures are sought, rather than individual specimens showing precise intermediacy in all anatomical structures. Evolutionists consider a transitional structure to be one that shows characteristics of an ancestor and characteristics of a descendent. Thus a number of fossils sometimes called reptile-like mammals show characteristics of mammals and also of more primitive tetrapods. These characteristics are especially clear in the skull, and particularly the lower jaw.
It would take a very long essay to criticize all or even most of the misleading, or just plain wrong, statements Johnson makes about evolutionary biology. For example, "Darwinists do not in principle deny the fundamental discontinuity of the living world, but they explain it as being due to the extinction of vast numbers of intermediates that once linked the discrete groups to their remote common ancestors" (p. 87). Wrong. First of all, the discontinuity of modern groups is not something embarrassing to "Darwinists" which they are trying to deny. Discontinuity exists, and it exists because of the process of speciation, which produces reproductively isolated groups of organisms through a number of well-understood processes of heredity. The hierarchy of taxa produced by evolution would be discrete regardless of whether we had examples of every intermediate species. It is just how we expect evolution to work, but Johnson does not understand this. As one reads the book, one stops over and over to say, "No, that's not quite right." It is as if Johnson is talking about a familiar topic, but he gives it a spin that requires careful reading- sort of like discussing a zebra as a horse-like quadreped distinguished by a stiff mane and black and red stripes.
Johnson demonstrates another problem that I have not seen discussed in many other reviews (see Hull, 1991, Hurwitt, 1991, Jukes, 1991, Quinn, 1991, Gray, 1992.) He clearly does not understand the meanings scientists give to many of their terms. He deliberately conflates pairs of ideas that properly are separate. I have selected a few of these for discussion.
Evolution is Not Evolutionism
First, Johnson defines evolution as if it were an ideology: evolutionism. Evolutionism to him is a philosophy that excludes the possibility of divine intervention occurring during evolution. Some individuals have made an ideology out of evolution, but Johnson errs in assuming that therefore evolution itself is an incorrect explanation of the history of the universe.
The quality or usefulness of a scientific idea is independent of the philosophical implications one may or may not draw from it. The fact that one can take a scientific idea and make an ideology out of it does not mean that every treatment of this idea will require an ideological treatment. If a high school teacher someplace should decide that photosynthesis is the foundation for a new religion, that doesn't mean that other teachers should cease teaching photosynthesis. Yet Johnson worries greatly that children will learn evolutionism rather than "just" evolution, and then lose their faith in there being a purpose for life. In this regard, let me reassure Johnson that in speaking with hundreds of teachers all over the country, I have found that when evolution is taught, evolution is taught, not evolutionism. Most teachers appear to be strongly (and conventionally) religious. I know of no recent national survey, though a recent survey of Texas teachers shows a high degree of church attendance (80%) (Markley, 1991).
Science is not Philosophical NaturalismJohnson protests that Darwinism cannot be extricated from atheistic, materialist philosophy. Evolution is defined in Darwin on Trial as "fully naturalistic evolution, — meaning evolution that is not directed by any purposeful intelligence" (p. 4). In this he errs, as do many "scientific" creationists, in conflating the necessary methodological materialism of science with philosophical materialism or naturalism. Naturalism is a philosophy stating that God does not have anything to do with the universe, about which science, as a non-theistic (rather than anti-theistic) enterprise, can say nothing. Like the more familiar ICR creationists, Johnson doesn't want to allow science to be a purely naturalistic, materialist exercise; he insists on the right to retain the possibility of divine intervention or guidance.
Unfortunately, for him, that is just not the way science operates in the late 20th century, and for good reason. Naturalistic explanations have been found to be far more fruitful in the explanation of natural phenomena than supernatural ones. The problem with supernatural explanations is that, correct or incorrect, they cannot be rejected, and science proceeds by rejecting explanations rather than "proving" them true. If you want to know whether the earth goes around the sun or the sun goes around the earth, you'll get a lot farther if you posit testable, natural explanations rather than untestable ones from supernatural revelation. The Hare Krishnas, based on their understanding of the Vedas, believe that the sun is closer to the earth than is the moon. Do you want revelation or empiricism to determine where to send the Apollo mission?
Evolution Is Not the Same As DarwinismJohnson conflates evolution and Darwinism, believing that by disproving Darwinism, he can demonstrate that evolution could not have occurred.
Evolution is a statement about the history of the universe: that the universe has a past. The message of evolution essentially is that change has occurred, as opposed to special creation's view that all the galaxies, solar systems, planets, and organisms in the universe were specially created all at one time. The difference between an evolutionist and a creationist is not "Did God create?", but "What is the history of the universe?" Did everything we see today occur all at one time, or is the universe of today different than it was in the past? Also, evolution refers to a very broad spectrum of natural phenomena: from galaxies and stars and solar systems, to geological phenomena, to organic life.
Darwinism is a mechanism by which part of this spectrum of history may be explained, in whole or in part. Darwinism attempts to explain organic evolution, at least in major part, by natural selection. But Darwinism is only one possible explanation for the history of life. If Darwinism were to be discovered not to explain organic evolution, this would have nothing in the universe (literally) to do with whether stellar or galactic evolution took place — or even whether organic evolution took place. Johnson does not recognize that by trying to disprove organic evolution by natural selection, he leaves untouched the explanation of organic evolution by other mechanisms. But he really doesn't care. His main concern is whether human evolution, one small component of this great sweeping theory, is adequately explained by natural causes, or requires supernatural purpose and design.
The Origin of Life is Not the Same as Evolution
Like the scientific creationists, Johnson confuses the origin of life and the Big Bang (the origin of the universe) with evolution. This is rather like confusing starting up the car's engine with driving away. It is necessary to start the engine to go anywhere, but there is nothing inherent about starting the car that tells you whether you are going to work, or to the corner store, or just idling in the driveway. The origin of life and the Big Bang are both interesting scientific problems, and, as they do with any scientific problem, scientists are attempting to explain them with natural rather than supernatural explanations. Clearly, there is much more to be learned about both, but it appears as if it is possible to explain these phenomena naturally. This possibility is offensive, however, to creationists, who demand that supernatural forces must be invoked. Still, logically, whether the origin of the universe and the production of the first replicating molecule are ever fully explained with naturalistic explanations has nothing to do with what happened subsequently. Did evolution take place, or not?