Evolution and Christian Belief (1)
Evolution and Christian Belief (1)
Abstract and Keywords
This chapter begins with a brief overview of the four chapters in the first part of the book, which looks into alleged conflict between religion and modern science, in particular Christian belief and science. It discusses the tensions between Christianity and evolution, and considers the sources of this conflict. It then analyzes the claims of the world's best known atheist, Richard Dawkins, and concludes that Dawkins gives us no reason whatever to think that current biological science is in conflict with Christian belief.
In the first part of this book, I propose to look into alleged conflict between religion and modern science. I’ll be concerned in particular with Christian belief and science; most of the alleged conflicts, however, have to do with theism, belief that there is such a person as God, rather than with doctrines that separate specifically Christian belief from other theistic religions such as Islam and Judaism. Most of what I say, therefore, will apply to other theistic religions as well as to Christianity. Chapters 1 and 2 will deal with tensions between Christian or theistic belief and evolution. Chapters 3 and 4 will examine the claim that God's acting specially in the world (miracles, but other kinds of direct action as well) is incompatible with science. They will also briefly address two further claims: the claim that the so-called scientific worldview (what Peter Unger calls the “Scientiphical worldview”) is incompatible with religious belief, and the claim that religion and science are incompatible because the epistemic attitudes characteristic of them are incompatible.1
It would be a serious matter if any of these alleged conflicts were genuine. First, science is widely and justly celebrated as a splendid intellectual achievement—perhaps mankind's most splendid effort along these lines; but then any human enterprise in serious conflict (p.4) with it has some explaining to do. Second, science does or should enjoy particularly high regard among Christians. A central feature of Jewish, Christian, and at least some strands of Islamic thought is the doctrine of the imago dei; we human beings have been created in the image of God. A central feature of that idea is that we resemble God not just in being persons, beings who can think and feel, who have aims and intentions, who form beliefs and act on those beliefs, and the like; we resemble God more particularly in being able to know and understand something of ourselves, our world, and God himself. Thus Thomas Aquinas:
Since human beings are said to be in the image of God in virtue of their having a nature that includes an intellect, such a nature is most in the image of God in virtue of being most able to imitate God;
Only in rational creatures is there found a likeness of God which counts as an image…. As far as a likeness of the divine nature is concerned, rational creatures seem somehow to attain a representation of [that] type in virtue of imitating God not only in this, that he is and lives, but especially in this, that he understands.2
Of course the idea of the imago dei has been understood in many ways. Some Lutheran and Reformed Creeds (e.g., the Belgic Confession, the Westminister Confession, the Heidelberg Catechism) seem to deny that we human beings still display the image of God; they speak of that image as constituted by “righteousness, knowledge and holiness” (Heidelberg Catechism) and declare that this image was lost (or mostly lost) in the fall. But here there may be less disagreement than meets the eye; the apparent disagreement may be mainly terminological. (p.5) Some Reformed thinkers distinguish a broad image of God (as with Aquinas, including personhood, rational faculties, knowledge of right and wrong) from a narrow image (righteousness, knowledge of God, and holiness); those who claim that the image of God was lost in the fall are thinking of the narrow image, and presumably would not make the same claim about the broad image. Furthermore, all the creeds presuppose that human beings display that broad image.
Although we are divine image-bearers, our knowledge and understanding is of course partial and fragmentary and often shot through with error; nevertheless, it is real. Taken naively but (so I say) accurately, modern science is an enormously impressive attempt to come to know something about ourselves and our world. (Think, for example, of the development of physics from Newton's day to ours: surely an unexcelled display of cooperative intellectual power and depth.) Modern science is therefore a most impressive way in which humankind communally reflects the divine nature, a striking development of the image of God in humanity. Accordingly it is to be prized by Christians and other theists; but then conflict between religion and science, from that perspective, is initially anomalous, disturbing, perplexing.
Like it or not, however, there is and has been at any rate apparent conflict.3 Many Christians have at least the vague impression that modern science is somehow unfriendly to religious belief; for other believers it is less a vague impression than a settled conviction. Similarly, many scientists and science enthusiasts argue that there is opposition between serious religious belief and science; indeed, some claim that religious belief constitutes a clear and present danger to science. Still others see religious belief as (p.6) steadily dwindling in the face of scientific advance. Tension between religion and science goes back at least to the seventeenth century, where the alleged conflict centered on astronomy.4 There is the famous Galileo affair, often portrayed as a contest pitting the Catholic hierarchy (representing the forces of repression and tradition, the voice of the Old World, the dead hand of the past, etc.) against the forces of progress and the dulcet voice of sweet reason and science. This way of looking at the matter dates back to Andrew Dixon White and his rancorous History of the Warfare of Science and Theology. White, in his characteristically restrained and judicious way, describes Galileo's ecclesiastical opponents as “a seething, squabbling, screaming mass of priests, bishops, archbishops, and cardinals.”5 Of course this way of looking at the matter is enormously simplistic; much more was involved.6 The dominant Aristotelian thought of the day was heavily a prioristic; hence part of the dispute was about the relative importance, in astronomy, of observation as opposed to a priori thought. Also involved were questions about what the Christian (and Jewish) Bible teaches in (p.7) this area: does a passage like Joshua 10:12–15 (in which Joshua commands the sun to stand still) favor the Ptolemaic (or Tychonic) system over the Copernican? Naturally enough, the usual struggle for power and authority was also present.7 Nevertheless there certainly did seem to be at least some degree of conflict between the developing modern science and Christian belief, or at any rate ideas closely associated, at the time, with Christian belief.
In the seventeenth century, the main source of debate and conflict was astronomical; since the middle of the nineteenth it has been biological, centering on the theory of evolution. Many Christian fundamentalists and evangelicals find incompatibility between the contemporary Darwinian evolutionary account of our origins and their version of the Christian faith. Many Darwinian fundamentalists (as the late Stephen Jay Gould called them) second that motion: they too claim that Darwinian evolution is flatly inconsistent with classical Christian or even theistic belief. Contemporaries who champion this conflict view include, for example, Richard Dawkins (The Blind Watchmaker, A Devil's Chaplin), Daniel Dennett (Darwin's Dangerous Idea), and, far to the opposite side, Phillip Johnson (Darwin on Trial). In Darwin's own day, this opposition and strife could assume massive proportions. Now Darwin himself was a shy, retiring sort who hated public controversy and confrontation; but given what he had to say, he was often embroiled in violent controversy. Fortunately for him, there was his friend Thomas H. Huxley, who defended Darwin with such fierce tenacity that he came to be called “Darwin's bulldog.” Huxley himself continued the canine allusion by referring to some of Darwin's opponents as “curs who will bark and yelp.”8 The canine (p.8) connection has proved resilient, or at least durable, extending all the way to the present, where we have Discover Magazine (September 2005) calling Richard Dawkins “Darwin's Rottweiler,” and Gould referring (no doubt unkindly) to Daniel Dennett as “Dawkins's lapdog.”
Many have claimed, therefore, that there is deep incompatibility between evolution and Christian belief and hence between religion and science; but are they right? To investigate the question we must know how to think of Christian belief. Suppose we take it to be defined or circumscribed by the rough intersection of the great Christian creeds: the Apostle's Creed, the Nicene Creed, and the Athanasian Creed, but also more particular creeds such as the Catholic Baltimore Catechism, the Reformed Heidelberg Catechism, the Belgic Confession and Westminster Confession, Luther's Small Catechism, and the Anglican Thirty-Nine Articles; the result would be something like the “Mere Christianity” of which C. S. Lewis spoke.
In the same way, we must specify how we are to think of evolution. The term covers a multitude—not necessarily a multitude of sins, but a multitude nevertheless. (1) There is the claim that the earth is very old, perhaps some 4.5 billion years old: the ancient earth thesis, as we may call it. (2) There is the claim that life has progressed from relatively simple to relatively complex forms (though in terms of sheer bulk or weight the simple forms still vastly overshadow the complex; bacteria outweigh all other living creatures combined). In the beginning there was relatively simple unicellular life, perhaps of the sort represented by bacteria and blue-green algae, or perhaps still simpler unknown forms of life. (Although bacteria are simple compared to some other living beings, they are in fact enormously complex creatures.) Then more complex unicellular life, then relatively simple multi-cellular life such as seagoing worms, coral, and jellyfish, then fish, then amphibia, then reptiles, birds, mammals, and finally, (p.9) as the current culmination of the whole process, human beings: the progress thesis, as we humans may like to call it (jellyfish might have a very different view as to where the whole process culminates). (3) There is the thesis of descent with modification: the enormous diversity of the contemporary living world has come about by way of offspring differing, ordinarily in small and subtle ways, from their parents.
Connected with the thesis of descent with modification is (4) the common ancestry thesis: that life originated at only one place on earth, all subsequent life being related by descent to those original living creatures—the claim that, as Gould puts it, there is a “tree of evolutionary descent linking all organisms by ties of genealogy.” According to the common ancestry thesis, we are all cousins of each other—and indeed of all living things. Horses, bats, bacteria, oak trees, and even poison ivy—we are all cousins of them all; you and the summer squash in your backyard are cousins under the skin (rind).9 (5) There is the claim that there is a naturalistic mechanism driving this process of descent with modification: the most popular candidate is natural selection operating on random genetic mutation, although some other processes are also sometimes proposed. Since a similar proposal was characteristic of Darwin (“Natural selection,” he said, “has been the main but not exclusive means of modification”), call this thesis Darwinism.
Finally (although this thesis is not part of evolution strictly so-called), it is often assumed that (6) life itself developed from nonliving matter without any special creative activity of God but just by virtue of processes described by the ordinary laws of physics and chemistry: call this the naturalistic origins thesis. These six theses are (p.10) of course importantly different from each other. They are also logically independent in pairs, except for the third and fifth theses: the fifth entails the third, in that you can’t sensibly propose a mechanism for a process without supposing that the process has indeed occurred. Suppose we use the term “evolution” to denote the first four of these; the fifth thesis, Darwinism, is stronger than evolution (so defined) and points to the mechanism allegedly underlying evolution; and the sixth isn’t really part of the theory of evolution.
So where does real or apparent conflict arise? Many Christian evangelicals or fundamentalists accept a literal interpretation of the creation account in the first two chapters of Genesis (as well as the genealogies in the next few chapters); they are inclined therefore to think the earth and indeed the universe vastly younger than the billions of years of age attributed to them by current science.10 This seems to be a fairly straightforward conflict, and hence part of the answer to our question is that current scientific estimates of the age of the earth and of the universe differ widely (not to say wildly) from scripturally based beliefs on the part of some Christians and other theists (Muslims for example). Of course Christian belief just as such doesn’t include the thought that the universe is young; and in fact as far back as Augustine (354–430) serious Christians have doubted that the scriptural days of creation correspond to 24-hour periods of time.11
(p.11) A more important source of conflict has to do with the Christian doctrine of creation, in particular the claim that God has created human beings in his image. This requires that God intended to create creatures of a certain kind—rational creatures with a moral sense and the capacity to know and love him—and then acted in such a way as to accomplish this intention. This claim is clearly consistent with evolution (ancient earth, the progress thesis, descent with modification, common ancestry), as conservative Christian theologians have pointed out as far back as 1871. Thus, for example, Charles Hodge, the distinguished Princeton theologian, speaking of the design of plants and animals: “If God made them, it makes no difference how He made them, as far as the question of design is concerned, whether at once or by a process of evolution.”12 What is less obvious is that it is also consistent with Darwinism, the view that the diversity of life has come to be by way of natural selection winnowing random genetic mutation. For example, God could have caused the right mutations to arise at the right time; he could have preserved populations from perils of various sorts, and so on; and in this way he could have seen to it that there come to be creatures of the kind he intends.
You might wonder whether random genetic mutations could be caused by God: if these mutations are random, aren’t they just a matter of chance? But randomness, as construed by contemporary biologists, doesn’t have this implication. According to Ernst Mayr, the dean of post-WWII biology, “When it is said that mutation or variation is random, the statement simply means that there is no correlation between the production of new genotypes and the adaptational needs of an organism in a given environment.”13 Elliott Sober, one of the most respected contemporary philosophers of biology, (p.12) puts the point a bit more carefully: “There is no physical mechanism (either inside organisms or outside of them) that detects which mutations would be beneficial and causes those mutations to occur.”14 But their being random in that sense is clearly compatible with their being caused by God.
What is not consistent with Christian belief, however, is the claim that this process of evolution is unguided—that no personal agent, not even God, has guided, directed, orchestrated, or shaped it. Yet precisely this claim is made by a large number of contemporary scientists and philosophers who write on this topic. There is a veritable choir of extremely distinguished experts insisting that this process is unguided, and indeed insisting that it is a part of contemporary evolutionary theory to assert that it is unguided, so that evolutionary theory as such is incompatible with Christian belief. According to Gould, “Before Darwin, we thought that a benevolent God had created us.”15 After Darwin, though, he says, we realize that “No intervening spirit watches lovingly over the affairs of nature.”16 Gould's sentiments are stated more clearly by the biologist George Gaylord Simpson:
Although many details remain to be worked out, it is already evident that all the objective phenomena of the history of life can be explained by purely naturalistic or, in a proper sense of the sometimes abused word, materialistic factors. They are readily explicable on the basis of differential reproduction in populations (the main factor in the modern conception of natural selection) and of the mainly random interplay of the known processes of (p.13) heredity…. Man is the result of a purposeless and natural process that did not have him in mind.17
Among the most eloquent and influential spokespersons for this incompatibility claim (the soloists, we might say) are Richard Dawkins in The Blind Watchmaker (1986), River Out of Eden (1996), Unweaving the Rainbow (1998), and A Devil's Chaplain (2003), and Daniel Dennett in Darwin's Dangerous Idea (1995). Both Dawkins and Dennett assert, loudly and slowly, as it were, that evolution and Christian belief are incompatible. But are they right? Is this claim true? Is there any reason to believe it? Here the best course is to look carefully at what these writers actually say, thus avoiding the danger of attacking straw men. Let's begin with Dawkins.
Richard Dawkins has retired from his post as Charles Simonyi Professor of the Public Understanding of Science at Oxford. Dawkins is the world's best known atheist (for what that's worth) and the world's most popular science writer. He is also an extremely gifted science writer; his account in The Blind Watchmaker, for example, of bats and their ways is a brilliant and fascinating tour de force.18 In the series of books I just mentioned he states his claim: the enormous variety of the living world has been produced by natural selection winnowing some form of genetic variability—unguided by the hand of God or any other person. Probably his most widely known declaration to that effect is to be found in The Blind Watchmaker: (p.14)
All appearances to the contrary, the only watchmaker in nature is the blind forces of physics, albeit deployed in a very special way. A true watchmaker has foresight: he designs his cogs and springs, and plans their interconnections, with a future purpose in his mind's eye. Natural selection, the blind, unconscious automatic process which Darwin discovered, and which we now know is the explanation for the existence and apparently purposeful form of all life, has no purpose in mind. It has no mind and no mind's eye. It does not plan for the future. It has no vision, no foresight, no sight at all. If it can be said to play the role of watchmaker in nature, it is the blind watchmaker.19
The very subtitle of this book trumpets his theme: “Why the evidence of evolution reveals a universe without design.” Now it is part of Christian and other theistic belief that God has created human beings, and created them in his own image. Obviously, if Dawkins's claim is true, this claim is false. The latter requires that God intended to create creatures of a certain kind—creatures “in his image”—and then acted in such a way as to see to it that they come into existence. This claim does not require that God directly created human beings, or that he didn’t do it by way of an evolutionary process, or even that he was especially interested in creating precisely our species (or even you and me). But if he created human beings in his image, then at the least he intended that there be creatures of a certain sort, and acted in such a way as to guarantee that creatures of that sort came to be. Dawkins's claim—that the living world emerged by way of unguided natural selection—is clearly incompatible with this claim. We shall have to look into his reasons. Why does he think that natural selection is blind and unguided? Why does he think that “the evidence of evolution reveals a universe without design”? How does the evidence of evolution reveal such a thing?
(p.15) Well, what, exactly, does current evolutionary science claim? That's not entirely easy to say; you can’t find an authoritative statement of it emblazoned on the walls of the National Academy of Science or anywhere else; there is considerable diversity of opinion as to what, precisely, are the essentials of contemporary evolutionary theory. Dawkins, for example, apparently thinks once life began, it was more or less inevitable that we would wind up with a living world very much like the one we see. Gould disagreed: he thought that if “the tape were rewound and then let go forward again,” chances are we’d get something wholly different. Writers also differ as to how much natural selection explains, how much must be explained in other ways, and how much is left unexplained.
For simplicity (and because we are thinking about Dawkins, an enthusiast for natural selection), let's stick with what above I called “Darwinism,” the idea that the main or possibly even only mechanism driving the whole process of evolution is natural selection culling random genetic mutation. A Darwinist will think there is a complete Darwinian history for every contemporary species, and indeed for every contemporary organism.20 Start with the population of prokaryotes (e.g., bacteria and blue-green algae) to be found on earth some 3 billion years ago. There is in principle a complete history specifying which genetic mutations occurred with respect to each member of that population, which of these mutations were heritable and adaptive, and which then successfully spread through the population. This history would go on to specify (vagueness aside) when, as a result of this process, the first single-celled eukaryotes (creatures with a proper nucleus) appeared; it would then describe how, in this way, the first new species came to be, the first new genera, the first new phyla, and so on. It would proceed through the Cambrian explosion, specifying in complete (p.16) detail which adaptive and heritable mutations arose at what times and in which creatures, and how they then spread through the population, eventually issuing in that remarkable eruption of life forms. Continuing over the eons, this history would trace in detail the development of all forms of life: the invertebrates, the various forms of vertebrate life including fish, reptiles, birds, and mammals; it would end with a description of all the contemporary forms of life.
This history, if written, would occupy an enormous library: call it the Library of Life. The claim is not, of course, that we are or ever will be in possession of that library. We don’t have anything like detailed knowledge of any of the books it contains, or even of any chapters or passages in any of those books. The Darwinian claim is only that (1) there is such a history, (2) there is good evidence for current views as to the overall shape of the history, and (3) we have some informed guesses as to how, at a high level of abstraction, some of the transitions occurred: examples would be the sorts of guesses made by Dawkins as to the origin and development of the mammalian eye, or the common suggestion that the bones in the mammalian middle ear developed from the reptilian jawbone.
Now there is nothing here, so far, to suggest that this whole process was unguided; it could have been superintended and orchestrated by God. For all the library says, God could have achieved the results he wanted by causing the right mutations to arise at the right times, letting natural selection do the rest. Another possibility: Thomas Huxley, Darwin's bulldog, was an agnostic (and in fact invented the term); nevertheless he suggested that God could have set things up initially so that the right mutations would be forthcoming at the right times, leading to the results he wanted.21 No (p.17) doubt there are other ways in which he could have directed and orchestrated the process. Dawkins's claim, of course, is that there is no such intelligent agent guiding the process; “the evidence of evolution,” he says, “reveals a universe without design.” What makes him think this is true? How does he propose to argue for this claim?
Not, naturally enough, by specifying chapter and verse in relevant volumes of the library and showing or even arguing that the processes involved in those transitions were not in fact overseen or guided by such an agent; our powers are a bit slim for that. Instead, he tries to show that it is possible that unguided natural selection should have produced all these wonders; it could be that they have all come to be just by virtue of unguided natural selection. He does this, first, by attacking arguments for the conclusion that natural selection could not have done so. Or rather, he attacks certain kinds of such arguments, ignoring others. Among those he ignores, for example, is John Locke's claim that “it is as impossible to conceive that ever pure incogitative Matter should produce a thinking intelligent Being, as that nothing should of itself produce Matter.”22 Many have concurred with Locke, but Dawkins fails to so much as mention this kind of claim. Nor does he try to show either that there is no such person as God, or that, if there is, it is not possible that he should have somehow set up and directed the whole process.23 And why should he? After all, he's a biologist and not a philosopher.
Instead, Dawkins tries to refute some of the more specific and specifically biological arguments to the effect that unguided natural (p.18) selection could not have produced certain of the wonders of the living world—the mammalian eye, for example, or the wing, or the bat's sonar. He argues that the objectors have not made their case. Here he sometimes stumbles; for example, he apparently confuses the question “What good is 5 percent of an eye?” with “What good is 5 percent vision?”: “An ancient animal with 5 per cent of an eye,” he says, “might indeed have used it for something other than sight, but it seems to me at least as likely that it used it for 5 per cent vision.”24 But not just any old 5 percent of an eye will produce 5 percent vision; indeed there may not be any 5 percent of an eye that produces 5 percent vision.
Just for purposes of argument, let's concede that Dawkins succeeds in refuting each of these claims of impossibility. Clearly that doesn’t entail that the impossibility claims are false; it shows only that certain arguments for them are not cogent. The question still remains: is it possible that unguided natural selection generate all the stunning marvels of the living world? Dawkins puts this question in the following tripartite fashion:
(3) Is there a continuous series of Xs connecting the modern human eye to a state with no eye at all?
(4) Considering each member of the series of hypothetical Xs connecting the human eye to no eye at all, is it plausible that every one of them was made available by random mutation of its predecessor?
(5) Considering each member of the series of Xs connecting the human eye to no eye at all, is it plausible that every one of them worked sufficiently well that it assisted the survival and reproduction of the animals concerned?25
(p.19) Compressing things a bit, we could put the question as follows. Imagine a three-dimensional space—“organic space,” as we might call it—where each of the countably infinite points is a possible life form. Then the Big Question is:
(BQ) Is there a path through organic space connecting, say, some ancient population of unicellular life with the human eye, where each point on the path could plausibly have come from a preceding point by way of a heritable random genetic mutation that was adaptively useful, and that could plausibly then have spread through the appropriate population by way of unguided natural selection?26
A couple of comments on (BQ). First, the human eye is just a stand-in for life forms generally; the question is not merely whether the human eye could have developed in this way, but whether all the current life forms could have. Second, we must start with an actual (not merely possible) population of unicellular life, a population that did in fact exist: the claim is that human beings (and hence the human eye) could have developed via unguided natural selection from some population of unicellular organisms that actually existed. Third, the other life forms on the path—the ones “between” the population of unicellular organisms and human beings—must be possible, but need not be actually existent. (That is, they need not be actually instantiated or exemplified; it's enough if they are possibly instantiated.) Dawkins is really asking whether it is plausible that the human eye develop in this way, starting from some population of unicellular organisms. Of course if in fact the eye did develop in this way, there would have to be such a path connecting life forms that had existent (p.20) instantiations. Fourth, the points on the path will have to be temporally indexed, with the temporal distance between a pair of points on the path being sufficient for the relevant mutation to spread through the population in question. That means that the time elapsed from that initial population of unicellular organisms to the appearance of the eye imposes a constraint on the number of points the path in question can contain and the temporal distance between them; the number of points the path contains and the temporal distance between them can be large but is not unlimited.
Finally, and crucially, what is the force of “could plausibly” in “each point along the path is such that it could plausibly have come from a preceding point on the path by way of a heritable random genetic mutation?” We’re not talking broadly logical possibility, of course; we’re not asking whether there is a possible world in which this development takes place. That would be much too weak; to use a Dawkinsian example, there are possible worlds in which the bronze statues in the park (constituted just as they presently are) wave goodbye when you leave. We are instead talking about something like biological possibility, and, as Dawkins thinks of biological possibility, it is to be explained in terms of probability. A given point on a path could plausibly have come from a preceding point by way of genetic mutation just if it is not too improbable that it do so. It might be possible in the broadly logical sense that a sufficiently complex single mutation take us all the way from a paradigm reptile to a paradigm mammal—possible, but far too unlikely. So the mutations must be reasonably probable, not too improbable, with respect to the previous point. Not too improbable, of course, apart from any special divine aid or special divine action. The mutation in question would have to occur and be caused in the usual way—by way of cosmic radiation, or x-ray, or chemical agent or whatever—but not by way of special divine action. How much improbability is too much? Here one can answer only in the vaguest terms. Dawkins suggests, sensibly enough, that (p.21) the improbability would have to be much less than that of that statue waving at us as we leave the park.
How does Dawkins answer (BQ), or rather, his tripartite version of it? (3), you recall, was the question “Is there a continuous series of Xs connecting the modern human eye to a state with no eye at all?” His reply: “It seems to me clear that the answer has to be yes, provided only that we allow ourselves a sufficiently large series of Xs.”27 No doubt he's right about (3); surely there is such a relevant series. We can see this as follows: consider a particular human eye—one of Dawkins's, for example; assign a number to each cell contained in that eye (as with certain kinds of build-it-yourself toy kits); let the first member of the series be a creature that has cell number 1, the second be one that contains cells number 2 and number 1; the third contain cell number 3 plus cells number 1 and 2, and so on. This won’t quite work; for this eye to function, there will also have to be an appropriate brain or part of a brain to which it is connected by an optic nerve. But you get the idea: clearly there is such a series. Of course that by itself doesn’t show much; if it's to be relevant, the length of the series will have to be constrained by the time available, and each step in the series will have to be such that it can arise by way of genetic mutation from a previous step. Furthermore (and crucially), each mutation will have to be fitness-conferring (or at least not unduly costly in terms of fitness), so that it's not too improbable that they be preserved by natural selection. This is where his answers to (4) and (5) come in.
Dawkins's answer to (4), (Considering each member of the series of hypothetical Xs connecting the human eye to no eye at all, is it plausible that every one of them was made available by random mutation of its predecessor?): “My feeling is that, provided the difference between neighboring intermediates in our series leading to the eye is sufficiently (p.22) small, the necessary mutations are almost bound to be forthcoming.” Finally question (5): Considering each member of the series of Xs connecting the human eye to no eye at all, is it plausible that every one of them worked sufficiently well that it assisted the survival and reproduction of the animals concerned? As Dawkins notes, some people claim that the obvious answer is “no”; he argues that they are mistaken. These people point to a particular structure or organ and claim that there isn’t a Darwinian series for that structure or organ; Dawkins makes suggestions as to how such a series might in fact go.
There are two basic ways in which Dawkins's argument is weak. First, returning to BQ, there is surely no guarantee that there is a not-too-improbable path through organic space from some early population of unicellular organisms to human beings, or, for that matter, to fruit flies. It might be, as Michael Behe claims, that some structures simply can’t be reached by way of small steps (each advantageous or not too disadvantageous) from preceding life forms.28 Among his proposed examples: the bacterial cilium, the cascade of electrical activity that occurs when a light sensitive spot is hit by a photon, blood clotting, the mammalian immune system, and the complicated molecular machines to be found in any living cell. Many have rejected Behe's specific arguments here; still, perhaps he's right. (I consider some of Behe's arguments in chapter 7.) Perhaps no matter how small you make the steps, there are life forms that can’t be reached from previous forms, except at the cost of astronomical, prohibitive improbability. How could we tell that this isn’t so? True, Dawkins says that his feeling is that indeed it isn’t so; but how much confidence can we put in feelings and guesses?
So the first weakness in Dawkins's argument is that the premises, his answers to questions (4) and (5) above, are controversial, (p.23) unsupported, and pretty much guesswork. There is no attempt at the sort of serious calculation that would surely be required for a genuine answer. No doubt such a calculation and hence an answer to those questions is at present far beyond our knowledge and powers; no doubt it would be unreasonable to require such a calculation; still, the fact remains we don’t have a serious answer.
But Dawkins's answers to (4) and (5) are correct; the argument is still in trouble. Recall that his answer to question (3) is yes, “provided only that we allow ourselves a sufficiently large series”; his answer to (4): “My feeling is that, provided the difference between neighboring intermediates in our series leading to the eye is sufficiently small…” But even if he is right about the answers to (3) and (4), it doesn’t follow that the whole path is plausibly possible in his sense—that is, it doesn’t follow that the path is not astronomically improbable. That is because of the temporal constraint imposed. Suppose there have been multicellular organisms for, say, a billion years. This means that the series can’t be arbitrarily long and the distance between the points arbitrarily small.
Dawkins's argument, therefore, is pretty weak. But what about the truth of his conclusion? Is there a Darwinian series for the eye, and for the other forms of life? Is Dawkins right? How can we tell? How could we determine a thing like that? Michael Behe is by no means the only biologist who thinks it's at best extremely unlikely that there is such a series; for example, according to the biologist Brian Goodwin,
It appears that Darwin's theory works for the small-scale aspects of evolution: it can explain the variations and the adaptations with species that produce fine-tuning of varieties to different habitats. The large-scale differences of form between types of organism that are the foundation of biological classification systems seem to require another principle than natural selection operating on small (p.24) variation, some process that gives rise to distinctly different forms of organism. This is the problem of emergent order in evolution, the origins of novel structures in organisms, which has always been one of the primary foci of attention in biology.29
Others, like Dawkins, think there is such a series.
On this point there is likely to be a difference between theists and nontheists. For the nontheist, undirected evolution is the only game in town, and natural selection seems to be the most plausible mechanism to drive that process. Here is this stunningly intricate world with its enormous diversity and apparent design; from the perspective of naturalism or nontheism, the only way it could have happened is by way of unguided Darwinian evolution; hence it must have happened that way; hence there must be such a Darwinian series for each current life form. The theist, on the other hand, has a little more freedom here: maybe there is such a series and maybe there isn’t; God has created the living world and could have done it in any number of different ways; there doesn’t have to be any such series. In this way the theist is freer to follow the evidence where it leads.
But the main point here lies in another direction. Dawkins claims that the living world came to be by way of unguided evolution: “the Evidence of Evolution,” he says, “Reveals a Universe Without Design.” What he actually argues, however, is that there is a Darwinian series for contemporary life forms. As we have seen, this argument is inconclusive; but even if it were air-tight it wouldn’t show, of course, that the living world, let alone the entire universe, is without design. At best it would show, given a couple of assumptions, that it is not astronomically improbable that the living world was produced by unguided evolution and hence without design.
(p.25) But the argument form
p is not astronomically improbable
is a bit unprepossessing. I announce to my wife, “I’m getting a $50,000 raise for next year!” Naturally she asks me why I think so. “Because the arguments against its being astronomically improbable fail! For all we know, it's not astronomically improbable!” (Well, maybe it is pretty improbable, but you get the idea.) If he's successful, what Dawkins really shows is that the arguments against there being a Darwinian series are not conclusive. What he shows, if he's successful, is that for all we know there is such a series, so that for all we know it's possible that the living world came to be in this fashion. We could put it like this: what he shows, at best, is that it's epistemically possible that it's biologically possible that life came to be without design. But that's a little short of what he claims to show.
It is perhaps worth noting and stressing the difference between claim and performance here. Dawkins claims that he will show that the entire living world came to be without design; what he actually argues is only that this is possible and we don’t know that it is astronomically improbable; for all we know it's not astronomically improbable. But mere possibility claims are not impressive. To put to better use an example proposed by Bertrand Russell and mentioned by Dawkins in his book The God Delusion, it's possible that there is a china teapot orbiting the sun between Earth and Mars, out of reach of our telescopes; this ought not to dispose us favorably to the thought that indeed there is a china teapot orbiting the sun between Earth (p.26) and Mars.30 But the same goes for the claim that a certain state of affairs is not astronomically improbable. Perhaps it isn’t; but that, so far, gives us no reason whatever to endorse it, and in fact doesn’t so much as make it sensible to endorse that claim.
Have I perhaps misinterpreted Dawkins? Some with whom I have discussed his argument have thought that he couldn’t possibly have intended an argument as weak as the one I’ve attributed to him; he must have additional premises in mind. Perhaps they are right; of course it is difficult to consider an argument when one is obliged to guess at its premises. Still, what might be other possibilities? What might Dawkins be thinking? Yehuda Gellman and Dennis Monokroussos have suggested (in personal communication) that perhaps Dawkins intends an argument connected with his claim, made in The Blind Watchmaker, that an attempt to explain the stunning variety of life by a hypothesis involving design is misguided in that any being able to create life would itself have to be too complex:
Organized complexity is the thing that we are having difficulty in explaining. Once we are allowed simply to postulate organized complexity, if only the organized complexity of the DNA/protein replicating machine, it is relatively easy to invoke it as a generator of yet more organized complexity…. But of course any God capable of intelligently designing something as complex as the DNA/protein machine must have been at least as complex and organized as that machine itself… To explain the origin of the DNA/protein machine by invoking a supernatural Designer is to explain precisely nothing, for it leaves unexplained the origin of the Designer.31
Design doesn’t explain organized complexity (says Dawkins); it presupposes it, because the designer would have to be as complex as what it creates (designs). Perhaps, therefore, Dawkins means to argue along the following lines: there are really just two explanations of life: unguided Darwinism and an explanation, (p.27) guided Darwinism, perhaps, that involves design. But the latter is really no explanation at all. Therefore the only candidate is the former.
Here there are two problems. First, this argument doesn’t depend on the facts of biology; it is substantially independent of the latter. Is it likely that Dawkins would be offering an argument of that sort? If so, why would he claim that it is “the Evidence of Evolution” that “Reveals a World Without Design”?
Set that problem aside for the moment; there is another and deeper problem with this argument. Suppose we land on an alien planet orbiting a distant star and discover some machine-like objects that look and work just like a 1941 Allis Chalmers tractor; our leader says “there must be intelligent beings on this planet—look at those tractors.” A sophomore philosophy student on the expedition objects: “Hey, hold on a minute! You have explained nothing at all! Any intelligent life that designed those tractors would have to be at least as complex as they are!” No doubt we’d tell him a little learning is a dangerous thing and advise him to take the next rocket ship home and enroll in another philosophy course or two. For of course it is perfectly sensible, in that context, to explain the existence of those tractors in terms of intelligent life, even though (as we can concede for present purposes) that intelligent life would have to be at least as complex as the tractors. The point is we aren’t trying to give an ultimate explanation of organized complexity, and we aren’t trying to explain organized complexity in general; we are only trying to explain one particular manifestation of it (those tractors). And (unless you are trying to give an ultimate explanation of organized complexity) it is perfectly proper to explain one manifestation of organized complexity in terms of another. Hence it is not the case, contra Dawkins, that an explanation in terms of divine design is a nonstarter. Such an explanation doesn’t constitute an ultimate explanation of organized complexity (if God is complex, nothing could constitute such an explanation); but it is none the worse for that.
A second point: Dawkins argues that “the main thing we want to explain” is “organized complexity.” He goes on to say that “the one thing that makes evolution such a neat theory is that it explains how organized complexity can arise out of primeval simplicity,” and he faults theism for being unable to explain organized complexity. Now first, in biology we are attempting to describe and explain terrestrial life, not organized complexity generally. And second: mind would be an outstanding example of organized complexity, according to Dawkins. Of course it is uncontroversial that if there is such a person as God, he would be a (p.28) being who thinks and knows; so suppose we take Dawkins to be complaining that theism doesn’t offer an explanation of mind. It is perfectly obvious that theists won’t be able to give an explanation of mind in general—they won’t be able to offer an explanation for the state of affairs consisting in there being at least one mind—because, naturally enough, there isn’t any explanation of the existence of God. But that is certainly not a point against theism. Explanations come to an end; for theism they come to an end in God. For any other view of the same level of generality they also come to an end. The materialist or physicalist, for example, doesn’t have an explanation for the existence of elementary particles or, more generally, contingent physical or material beings; that there are some is, from that perspective, a brute fact. It isn’t easy to say precisely what counts as begging the question; but to fault theism for failing to have an ultimate explanation of mind is as good a candidate as any.
Here is a second attempt to reconstrue Dawkins's argument.32 In The God Delusion he argues that the existence of God is monumentally improbable—about as probable as the assembly of a flight-worthy Boeing 747 by a hurricane roaring through a junkyard. Now it is not monumentally improbable, he says, that life should have developed by way of unguided Darwinism. In fact the probability that the stunning complexity of life came to be in that fashion is greater than the probability that there is such a person as God. An explanation involving divine design, therefore, is less probable than the explanation in terms of unguided Darwinism; therefore we should prefer unguided Darwinism to an explanation involving design; but these two are the only viable candidates here; therefore by an inference to the best explanation, we should accept unguided Darwinism.
Clearly a host of considerations clamor for attention here. Concede, for the moment, that unguided Darwinism is more probable than an explanation involving design; does it follow that the former is to be preferred to the latter? There is more to goodness in explanation than the probability of the explanans. And how secure is this alleged inference to the best explanation, as an argument form, or, more likely, maxim? If all the explanations are highly unlikely, am I obliged, nonetheless, to pick and endorse one of them? I hear a great roar from the Notre Dame stadium; either the Irish have scored a touchdown, or an extra point, or a field goal, or a safety, or completed a long pass, or made a long run (p.29) from scrimmage, or tackled the opposing runner for a loss, or intercepted a pass. Suppose these eight explanations exhaust the field, and suppose the first is slightly more probable than any of the other seven; its probability, on the evidence is .2. Am I obliged to believe that explanation, just because it is more probable than the rest, and even though its probability is much below .5? Whatever happened to agnosticism, withholding belief?
And why think the existence of such a person as God is unlikely in the first place? Dawkins is presumably speaking here of some kind of objective probability, not epistemic probability. Statistical probability hardly seems relevant; presumably, therefore, he's thinking of something like logical probability, something like the proportion of logical space occupied by the possible worlds in which there is such a person as God; his idea is that the more complex something is, the smaller that proportion is. (“God, or any intelligent, decision-taking calculating agent, is complex, which is another way of saying improbable.”)33 But the first thing to note is that according to Dawkins's own definition of complexity, God is not complex. According to his definition something is complex if it has parts that are “arranged in a way that is unlikely to have arisen by chance alone.”34 Here he's clearly thinking of material objects. Setting aside the excesses of mereological universalism, however, one thinks that immaterial objects, e.g., numbers, don’t have parts. But of course God isn’t a material object; strictly speaking, therefore, God has no parts. God is a spirit, an immaterial spiritual being; hence God has no parts at all. A fortiori God doesn’t have parts arranged in ways unlikely to have arisen by chance. Therefore, given the definition of complexity Dawkins himself proposes, God is not complex.
God has no parts; but isn’t God in some sense complex? Much ink has been spilled on this topic; but suppose, for the moment, we concede for purposes of argument that God is complex. Perhaps we think the more a being knows, the more complex it is; God, being omniscient, would then be highly complex. Perhaps so. But then why does Dawkins just assume that any such being would have to be such that its logical probability was small? Given materialism and the idea that the ultimate objects in our universe are the elementary particles of physics, perhaps a being that knew a great deal would be improbable—how (p.30) could those particles get arranged in such as way as to constitute a being with all that knowledge? But of course we aren’t given materialism.
So why think God would have to be improbable? According to classical theism, God is of course a being with knowledge—the maximal degree of knowledge—but is also a necessary being; it is not so much as possible that there should be no such person as God; God exists in every possible world. If God is a necessary being, if he exists in all possible worlds, then the (objective) probability that he exists, naturally enough, is 1, and the probability that he does not exist is 0. On the classical conception, God is a being who has maximal knowledge, but is also maximally probable. Dawkins doesn’t so much as mention this classical conception; he altogether fails to notice that he owes us an argument for the conclusion that this conception is impossible, or anyhow mistaken, so that there is no necessary being with the attributes of God. This version of his argument, therefore, fares no better than the others.
The conclusion to be drawn, I think, is that Dawkins gives us no reason whatever to think that current biological science is in conflict with Christian belief.
Of course Dawkins is not the only thinker to trumpet such conflict. Dawkins together with Daniel Dennett constitute the touchdown twins of current academic atheism: and Dennett follows Dawkins in claiming that evolutionary theory is incompatible with traditional theistic belief.35 In the next chapter we will see how Dennett develops this theme.
(1.) See, e.g., Unger's All the Power in the World (New York: Oxford University Press, 2005) and chapters 1 and 5 of Beyond Inanity, forthcoming.
(2.) Aquinas, Summa Theologiae Ia q. 93 a. 4; Summa Theologiae Ia q.93 a.6.
(3.) How, exactly (or even approximately) shall we understand conflict? Conflict comes in more than one form. There is straightforward inconsistency, there is inconsistency in the presence of obvious truths, there is probabilistic incompatibility, and more. I address these questions in chapters 5 and 6.
(4.) It is commonly claimed that the Copernican revolution signified a demotion for humanity by virtue of earth's being removed from the center of the universe; that is just one way among others, so goes the claim, in which earth's privileged place in the universe was compromised by the advance of science. This seems to be a mistake; in the earlier Aristotelian scheme of things, being at the center of the universe was definitely not an honor. It was the heavier, grosser elements that sank to the center; in Dante's Divine Comedy, the lowest circle of hell is at the very center of the universe; and according to Pico della Mirandola, Earth-dwellers inhabit “the excrementary and filthy parts of the lower world.” See Dennis R. Danielson, “The Great Copernican Cliché,” American Journal of Physics 69 (10) October 2001, pp. 1029ff.
(5.) White, History of the Warfare of Science with Theology in Christendom (New York: D. Appleton and Co., 1898). Quoted in Michael Murray's “Science and Religion in Constructive Engagement” in Analytic Theology, ed. Oliver Crisp and Michael Rea (New York: Oxford University Press, 2009), p. 234.
(6.) John Brooke, Science and Religion: Some Historical Perspectives (Cambridge: Cambridge University Press, 1991), pp. 8–9. See also the account of the Galileo affair in Jerome Langford, Galileo, Science and the Church (South Bend: St. Augustine's Press, 1998).
(7.) “If any simple explanation existed, it would rather be in terms of the customary ruthlessness of societal authority in suppressing minority opinion, and in Galileo's case with Aristotelianism rather than Christianity in authority” (Stillman Drake, Galileo (Oxford: Oxford University Press, 1980), v.
(8.) Thomas H. Huxley, letter to Darwin, November 23, 1859.
(9.) Why not suppose that life has originated in more than one place, so that we needn’t all be cousins? This suggestion is occasionally made, but the usual idea is that life originated just once—if only because of the astounding difficulty in seeing how it could have originated (by exclusively natural processes) at all.
(10.) Creationists often suggest that when God Created the world 6,000–10,000 years ago, he created it in a “mature state,” complete with crumbling mountains, fossils, and light apparently travelling from stars millions of light years distant. Here they can appeal to an unlikely ally: in The Analysis of Mind (London: Routledge, 1921), p. 159, Bertrand Russell wrote that we can’t disprove the proposition that the universe popped into being just five minutes ago, again, complete with apparent memories and other apparent traces of a much longer past.
(11.) Those Christians who think the world is much younger than current scientific estimates will indeed find a conflict here; they can see it as a superficial conflict as outlined in chapter 6. Concerning Augustine, see The Literal Meaning of Genesis, translated and annotated by John Hammond Taylor, S. J., 2 vols. (New York: Newman Press, 1982), vol. 1, chapter 1.
(12.) Hodge, What is Darwinism (New York: Charles Scribner, 1871).
(13.) Mayr, Towards a new Philosophy of Biology: Observations of an Evolutionist (Cambridge: Harvard University Press, 1988), p. 98.
(14.) Sober, “Evolution Without Metaphysics?” in J. Kvanvig (ed.), Oxford Studies in Philosophy of Religion, vol. 3.
(15.) Gould, Ever Since Darwin (New York: Norton, 1977), p. 267.
(16.) Gould, “In Praise of Charles Darwin,” in Darwin's Legacy (San Francisco: Harper & Row, 1983), pp. 6–7.
(17.) Simpson, The Meaning of Evolution (New Haven: Yale University Press, rev. ed., 1967), pp. 344–45.
(18.) Dawkins, The Blind Watchmaker (New York and London: Norton, 1986).
(19.) Dawkins, The Blind Watchmaker, p. 5.
(21.) Huxley as cited in Brooke, Science and Religion, p. 36. Clearly this suggestion raises difficult questions about determinism, the chanciness (if any) involved in quantum mechanics, the existence of counterfactuals of chance (that is, propositions specifying what would have happened, if a given chance process had occurred), and so on; some of these questions will be addressed in chapter 3.
(22.) Locke, Essay Concerning Human Understanding IV, x, 10.
(23.) Although in his later book The God Delusion (New York: Bantam, 2006) he offers some sophomoric arguments for the conclusion that it is extremely unlikely that there is such a person as God; see reviews by Thomas Nagel (“The Fear of Religion,” The New Republic, October, 2006), H. Allen Orr (“A Mission to Convert,” New York Review of Books, January, 2007), and myself (“The Dawkins Confusion: Naturalism ad Absurdum,” Books and Culture, March/April, 2007).
(24.) Dawkins, The Blind Watchmaker, p. 81.
(25.) Dawkins, The Blind Watchmaker, pp. 78–9.
(26.) Well, not quite. The relevant pathways through organic space need not be such that each step is a step towards the human eye; there could be brief regressions, feints in irrelevant directions, and so on; the process need not be entirely monotonic, to use Elliott Sober's term.
(27.) Dawkins, The Blind Watchmaker, p. 78.
(28.) Behe, Darwin's Black Box (New York: The Free Press, 1996); The Edge of Evolution (New York: The Free Press, 2007).
(29.) Goodwin, How the Leopard Changed its Spots (Princeton: Princeton University Press, 1994), p. ix.
(30.) Russell's “Is There a God?” was commissioned by Illustrated magazine in 1952, but never published; see Dawkins, The God Delusion, p. 52.
(31.) Dawkins, The Blind Watchmaker, p. 140.
(32.) Suggested in conversation (but not necessarily endorsed) by Sharon Street.
(33.) Dawkins, The God Delusion, p. 109.
(34.) Dawkins, The Blind Watchmaker, p. 7.
(35.) Although others also vie for that dubious distinction: among them are Sam Harris (The End of Faith (New York: Norton, 2004) and Christopher Hitchens (God Is Not Great (New York: Hachette Book Group, 2007).