The Mistrial of Evolution
A review of Phillip E. Johnson's Darwin on Trial

Review by Terry M. Gray


The following essay is an expanded and less edited version of an article that appeared in the Banner, April 13, 1992 under the title, "The Mistrial of Evolution". It is a review of the book, Darwin on Trial, by Phillip E. Johnson. The review is by Terry M. Gray, associate professor of chemistry at Calvin College.

Darwin on Trial by UC Berkeley law professor Phillip E. Johnson has been hailed by one prominent evangelical as the book of the decade and must reading by Christian scholars; others in the evangelical community have called it the first serious challenge to evolutionary science to appear in the past forty years. It is not often that someone with the pedigree of Dr. Johnson takes on the scientific establishment. (He is a Harvard and University of Chicago graduate and was a law clerk for a former Chief Justice of the US Supreme Court.) One must certainly sit up and take notice.

Johnson's critique of Darwinism is a two pronged attack. He convincingly shows that at the heart of much of evolutionary science is a commitment to atheistic naturalism. To the atheist, evolution is a philosophical necessity. Chapters entitled "The Rules of Science", "Darwinist Reli gion", "Darwinist Education", and "Science and Pseudo-science" make the point that the so-called scientific theory of evolution is embedded in an all pervasive atheistic, naturalistic world view that is espoused with all the fervor of any religious belief. Even in the chapters devoted to the alleged scientific evidence, he shows how commitments to naturalism (and against any kind of theism) affect the evaluation of the data. As a second line of attack Johnson evaluates the evidence marshalled by evolutionists in support of their theory. In chapters on natural selection, mutations, the fossil record, the argument from classification, fossils of transitional forms, molecular evidence, and theories on the origin of life Johnson weighs the various arguments and finds them unconvincing. He does this from the point of view of a lawyer (which by his own description is a specialist "in analyzing the logic of arguments and identifying the assumptions that lie behind those arguments").

While creationist critics of evolution will welcome the Berkeley professor as an ally, he distances himself from the so-called scientific creationists. He writes, "I am not interested in any claims that are based upon a literal reading of the Bible...If an omnipotent Creator exists He might have created things instantaneously in a single week or through gradual evolution over billions of years." In the first pages of the book he makes very important distinctions between scientific creationists (those who believe in a young-earth, six-day special creation), creationists (including old-earth, theistic evolutionists if they acknowledge divine control and purpose), and Darwinists (those who hold to "fully naturalistic evolution, involving chance mechanisms guided by natural selection"). For Christians who are also scientists, these distinctions are of utmost importance. Too often the two extreme categories are the only ones presented and we are asked to make a choice between a six, twenty-four hour day creation and atheistic evolution. In spite of having made these distinctions at the outset and in spite of occasionally reminding the reader of them, Johnson fails to maintain them consistently himself. Perhaps this is the greatest flaw of the whole book. In many cases the decisive consideration in rejecting the scientific evidence is that the spokesman for the evidence is an atheistic, naturalist with no other alternative but to accept a weak or otherwise inconclusive argument. My guess is that the average practicing evolutionist is not so intolerant of religious belief as some of the vocal and crusading scientists that Johnson cites. In addition there are a number of Christian biologists who are persuaded by the evidence and who find it possible to fit an evolutionary scenario into their understanding of the Biblical perspective. Johnson only aims his darts at the militant atheist and says nothing regarding the latter two groups.

THE MYTH OF RELIGIOUS NEUTRALITY

Phillip Johnson has served us well in pointing out the atheistic, naturalistic, and materialistic bias of much of modern science. That this is true of modern science, however, should not surprise us. We in the Reformed tradition have always asserted that human existence is fundamentally a religious response to the revelation of God around us. We either worship and serve the living and true God or we worship and serve creatures or created things (idolatry). The teaching of Romans 1:18ff. is that apart from the special grace of God, fallen humanity will suppress the truth and will not acknowledge God as God; this is the condition of all unbelievers, including unbelieving scientists.

Evolutionary biology is not the only science that uses its conclusions to support a naturalistic worldview. The motions of the planets and other objects are well explained by Newton's laws. The behavior of matter is understood in terms of atomic and mo lecular theories. Models in molecular biology and biochemistry are very successful in accounting for inheritance, disease, much physiology, and other biological phenomenon. To the unbelieving scientist, having a scientific explanation of some natural phenomenon is tantamount to saying that God is no longer needed as part of our explanation of the phenomenon. Even the weather, once thought by all to be in the domain of God's providence, is now being modeled with sophisticated computers with some degree of success. Why don't we get uneasy when chemists say that perfume diffusing from an open bottle to all parts of the room does so as a result of random, mechanical collisions between perfume and air molecules? (Interestingly, the 17th century theologians rejected the atomic theory on the basis that atomic explanations of matter were mechanistic and left no room for God.) The scriptures would have us see all phenomena, even those with scientific explanations, as occurring by the will and under the direct control of God; He is intimately involved in the Creation's moment by moment workings (see Ps. 104; 135:5-7; 147:16,17; Jer. 31:35). Although some will object to the use of the Aristotelian categories, I think that it is helpful to think in terms of primary cause (the sovereign activity of God) and secondary cause (those aspects of reality that can be described by scientific theory). Recognizing the secondary cause, the scientific explanation, does not necessarily imply rejection of the primary cause. Sometimes we speak as if God is not involved if we can't point to a direct special intervention; Johnson with all of his excellent distinctions suggests this when he says, "A God who can never do anything that makes a difference...is of no importance to us." Those who would seek to make the Creation their god will see the secondary cause as the ultimate cause and deny God's role; this, of course, is idolatry.

In a God-created world even unbelievers, as they study that creation, stumble upon the truth. The unbeliever lacks the ultimate reference point for all knowledge, the knowledge of God, and consequently his knowledge is only knowledge after a fashion. In the words of Cornelius Van Til, "He knows nothing at all as he ought to know anything." God graciously gives the unbeliever the grace (common grace) to learn true things about his creation, things that believers can use to understand God's creation. This is why believing science looks so similar to unbelieving science. (Sometimes I think that Christian scholars use the Biblical doctrine of common grace to permit the use of the "true" scholarship of unbelievers as if that scholarship were religiously neutral. We must remember that if unbelievers experience God's common grace in their lives it will be to their judgment if they don't respond in belief to God's revelation to them. Perhaps Christian scholars need to be more explicit in making their faith commitments known even when the scholarship appears not very different from that of unbelievers.)

In principle, then, Christians can accept the ideas of evolutionary biology in the same way that they acknowledge other mechanistic ideas in the physical sciences. As long as God's sovereign control, purpose, and design in Creation is recognized, the evolutionary account is a feasible description of the secondary causes involved. We can even include ideas of chance and randomness if we recog nize that there is no such thing as chance and randomness from God's point of view (Prov. 16:33). Once the in-principle acceptance of the theory has been established it is yet another question as to whether the scientific description comports well with the scriptural account in the early chapters of Genesis. Professor Johnson has not considered this matter in his book. Suffice it to say that historically, the consensus of Reformed theologians from both the conservative American Presbyterian tradition and the Dutch Reformed tradition has never rejected evolutionary theory on the basis of a literal six twenty-four hour day interpretation of Genesis 1.

THE SCIENCE

Professor Johnson reviews the evidences for evolution in Chapters 2 8. Although he is not a sympathetic reviewer, he is fair. He has covered most of the main lines of evidence and has even included the responses of evolutionists to their critics. I found the book to be an interesting summary of the arguments for evolution even though this was not the authorial intent. Johnson is not convinced that scientists have been able to account for the evolution of new species and major groups (macroevolution) or for novel features like eyes or wings. He claims that most of the evidence only proves that organisms are similar (not necessarily related) and that the proposed mechanisms for evolution (mainly natural selection acting on random mutations) are inadequate to produce anything but minor changes (microevolution).

Before turning to some specific responses to some Johnson's critiques, it is worth noting some examples of his debating style at key junctures in the argument. In the chapter on mutations he lets scientists like Richard Goldschmidt (the inventor of the "hopeful monster") criticize the standard Darwinian model. Goldschmidt and others believed that natural selection acting on very small changes was unable to produce the major changes observed over the course of evolution. He believed that mutations that had large-scale effects on the organism (macromutations, most likely a mutation in some key gene regulating development) were required to accomplish the sorts of the changes evolution required. Johnson cites Goldschmidt approvingly. He then turns to the Darwinists and lets them criticize and even ridicule Goldschmidt and the macromutationists, pointing out that such mutations are genetic impossibilities. Interestingly, neither side of this debate believed that their opponent's criticism was a death blow to their position nor did they believe that their own criticism suggested that evolution had not occurred. Yet this is precisely how Johnson uses them.

On a second and slightly related point is Johnson's discussion of the fossil record. He cites the observation that there are few transitional forms to be found in the fossil record, and that the fossil record suggests the sudden appearance of new groups rather than a gradual evolution. Stephen J. Gould and others have proposed a modification of the neo-Darwinian model of evolution called punctuated equilibrium that attempts to account for this observation. They argue that most of the time species remain unchanged (stasis ) and that the evolution of new species occurs rapidly (on the geological time scale). Johnson calls this adjustment of evolutionary theory the attempt of evolutionists to "deal with an embarrassing fact" as if such theory adjustments were abnormal in science. Frankly, I am impressed by the response of the evolutionists to the empirical data on this point. Again Johnson freely uses the punctuated equilibriumist's arguments to criticize the standard Darwinian model of gradualism. But then he rejects their argument on the ground that it requires macromutations, which he had rejected in the previous chapter.

It is not clear to me what kind of evidence Johnson would find persuasive. At one point in the argument he writes, "Success in dividing a fruitfly population into two or more separate populations that cannot interbreed would not consititute evidence that a similar process could in time produce a fruitfly from a bacterium. If breeders one day did succeed in producing a group of dogs that can reproduce with each other but not with other dogs, they would still have made only the tiniest step towards proving Darwin ism's important claims." There are other similar comments that suggest that no amount of evidence will convince him unless we can reproduce the whole of evolutionary history in the laboratory under controlled conditions. Of course, this is impossible; we are talking about processes for which 1000-10,000 years is a short period of time.

Now let's turn to some of the scientific arguments. As indicated above Johnson's rejection of macromutational events has allowed him to reject the main alternative to natural selection as a mechanism of change in evoluton and to reject punctuated equilibrium as an interpretation of the fossil record. This rejection may have been justified forty years ago when Goldschmidt proposed his "hopeful monster" and even up to ten or fifteen years ago. However, recent advances in molecular biology, especially in the area of molecular developmental biology, have shown that, indeed, there are genes that exercise global control over the morphology of the organism. These genes have been best studied in the fruitfly Drosophila, but similar genes have been found with similar functions in organisms ranging from yeast, to worms, to vertebrates, including human beings. In addition, the molecular biology of cancer has uncovered a class of genes known as oncogenes, genes which when mutated lead to cancers. A mutation in one of these genes can result in dramatic global effects. Interestingly, some of the oncogenes have turned out to be identical with the development genes. Mainstream Darwinists are not yet prepared to accept macromutations as a key mechanism in evolution, but some biologists are. In the 1991 edition of an upper-level undergraduate textbook in developmental biology the last chapter is devoted to the evolutionary implications of some of these recent findings. The author even suggests that there is a new synthesis on the horizon bringing together neo-Darwinism, molecular biology, developmental biology, and paleontology (punctuated equilibrium).

Johnson discusses the argument for evolution from homology (similarity among groups of organisms) in the chapter entitled "The Fact of Evolution". He dismisses this argument claiming that an equally plausible explanation is that similarities among groups of organisms are due "to a sort of blueprint called the 'Archetype,' which existed only in some metaphysical realm such as in the mind of God." Thus relationship between all the mammals (vertebrates with hair or fur that produce milk to feed their young) does not imply geneological relationship, i.e. that they all descended from a common ancestor, but only that they "conform in their 'essence' to the mammalian 'type.'" It seems to me that Johnson does not address the most powerful component of the argument from homology, the so-called panda's thumb argument. Here is some of Johnson's citation of Stephen J. Gould's discussion of this argument. "Evolution lies exposed in the imperfections that record a history of descent. Why should a rat run, a bat fly, a porpoise swim, and I type this essay with structures built of the same bones unless we all inherited them from a common ancestor." (emphasis mine) The examples could be multiplied. The panda's thumb that enables the flexibility required for eating bamboo is an adaptation of a wrist bone. The panda's true thumb (i.e., anatomically comparable to human thumbs) had been adapted for a different lifestyle in the ancestral bears (as in modern bears). The existence of a new kind of thumb as a result of the loss in history of the orginal thumb argues for descent from a common ancestor. We make these kinds of conclusions all the time when we think about similar features between nearly identical objects. Take for example New Testament manuscripts. When we find extant manuscripts that have inserted sentences or paragraphs (e.g., the concluding sentence in the Lord's Prayer) and compare them with other extant manuscripts that are otherwise identical, we do not conclude that these two manuscripts are completely independent in origin. We re-create the scenario that at some point in the manuscript history, a scribe either added or deleted the inserted text. All manuscripts deriving from that errant copy would also contain the error. One more example illustrates the same point and at the same time shows that if we take the evidence seriously, the evolutionary arguments extend even to human beings. Of all the mammals only guinea pigs and primates (including human beings) must have vitamin C in their diet. All the others have the biochemical machinery to make their own. This in itself sug gests that the ancestral mammal had the vitamin C synthesis capability, but that the ancestral guinea pig and the ancestral primate lost that ability and passed that defect to its ancestors.

The story becomes even more interest ing when the powerful methods of molecular biology are used. It is possible to develop a DNA probe that uniquely recognizes the key gene that allows for vitamin C synthesis in animals that do make their own. When this probe is used to study the DNA of guinea pigs and human be ings, the vitamin C gene is found. Further analysis shows that this gene is a pseudogene, i.e., it looks like a real gene, but it is not expressed due to a mutation in the gene itself or in the region of DNA that controls the expression of that gene. Now we could argue that in God's inscrutable purpose he placed that vitamin C synthesis look-alike gene in the guinea pig or human DNA or we could admit the more obvious conclusion, that humans and primates and other mam mals share a common ancestor. (Note: Before I am accused of espousing human evolution, let me state clearly and succinctly my present position. I do believe in a historical Adam and Eve who were the parents of the whole human race. A plausible interpretation of Genesis 2 regarding the creation of Adam that takes into account these evidences for human evolution is that God used some already evolved primate as starting material in his special creation of the unique image bearer, Adam. Granted, there are some exegetical and scientific arguments against this view, but so far I have found nothing better that allows me to be faithful to scripture and to the empirical evidence.)

Let me finish with some dis cussion of the molecular data. Johnson presents the molecular data more or less fairly, but I think that he left out the two most powerful arguments for evolution that the molecular data suggest. I find it absolutely striking that the family tree of organisms generated by a consideration of classification, by a consideration of the temporal sequence of the fossil record (for this argument the existence of transi tional forms is immaterial), and by the molecular data (by comparisons of protein or DNA sequences) all turn out to be roughly the same. I think that these really are independent evidences for common ancestry. (Darwin didn't even know what a protein sequence was; the biochemical data is less than 30 years old.) The second argument is even more persuasive. Although the molecular data does not address the macroevolution question, it does present a mechanism for the observation that organisms more closely related have more similar protein sequences. Changes in protein sequences are readily explained by mutations in the DNA. The way changes are introduced into the DNA from generation to generation is fairly well understood. My own research involves the study of mutants of a particular bacterial virus protein. From work in the laboratory, we know the geneological relationship between these strains of virus and the how that geneology is manifested by comparing the sequences of those proteins. The same sort of analysis is performed in the study of human genetic diseases such as hemophilia, sickle cell anemia, or cystic fibrosis. Changes in the DNA or protein of an organism is passed on to all of its descendents. We can trace lineages of organisms the same way we can trace lineages of ancient manuscripts. Thus the more recently two groups of organisms shared a common ancestor, the more similar their sequences should be.

In my view Phillip Johnson has not succeeded in his attempt to unseat the theory of evolution as the dominant view of the development of life on earth. There is some merit in his claim that atheistic evolutionists have so much at stake in maintaining the theory as the only acceptable creation account in town. I do wish he had spent more time discussing the views of Christian scientists who have found in the theory of evolution a reasonable explanation for the origin and diversity of life. These scientists may be able to be more objective because for them the metaphysical stakes are not so high.