bookmark_borderOpening Statement from My Debate with Frank Turek

Although I’ve recently been too busy to spend any time writing original content for this blog, I’ve decided to post my opening statement from my 2016 debate with Frank Turek. Enjoy!


Good evening! I’d like to thank Craig Freerksen for organizing this debate. I’d also like to thank Dr. Turek for agreeing to participate. Finally, I’d like to thank all veterans, including my opponent, for defending the right to have a debate like this. Now, speaking of our country, I thought I’d borrow a slogan from the presidential campaign. I’m not selling any hats, but I’m here to “make atheism great again.”


In this debate, we’ve been asked to assess what best explains reality: naturalism or theism? Before we can answer that question, we need to have some idea of what we’re talking about, so let me begin by defining some terms.
First, by “naturalism,” I mean the view that the physical exists and, if the mental exists, the physical explains why the mental exists.[1] If naturalism is true, then there are no purely mental beings which can exist apart from a physical body and so there is no God or any person or being much like God.
Second, by “supernaturalism,” I mean the view that the mental exists and, if the physical exists, the mental explains why anything physical exists.[2] If supernaturalism is true, then there is no purely physical matter which can exist without some sort of ultimate mental creator.
Third, “personal supernaturalism” is a type of supernaturalism; it adds on the claims that one or more personal mental entities exist and, if a physical world exists, it or they produced the physical world for a purpose.[3]
Fourth, “theism” is a type of personal supernaturalism; it adds on the claim that there is just one mental entity, God, who is all-powerful, all-knowing, and morally perfect.[4]
Finally, fifth, “otherism” is a catch-all category. It says that both naturalism and supernaturalism are false.[5]
Now the question before us in tonight’s debate is this. What best explains reality: theism or naturalism?
In support of a naturalistic answer to that question, I’m going to defend three basic contentions:
(1) The best explanation is the explanation with the overall greatest balance of intrinsic probability and accuracy;
(2) Naturalism is an intrinsically more probable explanation than theism; and
(3) Naturalism is a more accurate explanation than theism.

First Contention

Let’s look, then, at my first basic contention: the best explanation is the explanation with the overall greatest balance of intrinsic probability and accuracy.
By “intrinsic probability” of a hypothesis, I mean the probability independent of the evidence we have for or against it. The intrinsic probability of a hypothesis is determined entirely by its modesty and coherence.[6]
By “accuracy” of a hypothesis, I mean the degree to which a hypothesis’s predictions correspond to reality. We measure accuracy by looking at “evidence.”
By “evidence” I mean something which makes something else more probable than it would have been otherwise. Let me give you an example.[7] Imagine you have two jars of red and blue jellybeans. In the first jar, 90% of the jellybeans are blue and the rest are red. In the second jar, 90% of the jellybeans are red and the rest are blue.
Now imagine you are handed a jelly bean from one of the jars, but you don’t know which jar it came from. If it’s a blue bean, that’s evidence it came from the first jar, not the second. The blue bean doesn’t disprove that it came from the second jar because the second jar also has blue beans, but it’s more likely that it came from the first because there are more blue jellybeans in the first than in the second. Similarly, if it’s a red bean, that’s evidence it came from the second jar. The red bean doesn’t disprove that it came from from the first jar because the first jar also has red beans, but it’s more likely that it came from the second because it has many more red beans.
Mathematicians have a formula called Bayes’ Theorem, which can be used to specify the relationship between intrinsic probability, accuracy, and the overall or final probability of a hypothesis. It follows from Bayes’ Theorem that a hypothesis is probably true, just in case it has a greater overall balance of intrinsic probability and explanatory power than do its alternatives collectively.

Second Contention

Let’s look, then, at my second basic contention: naturalism is an intrinsically more probable explanation than theism.
Intrinsic probability is determined by modesty, coherence, and nothing else. By “modesty,” I mean a measure of how much the hypothesis asserts.[8] The more a hypothesis claims, the more ways there are for it to be false and so, before we start looking at evidence, the less likely it is to be true.
By “coherence,” I mean a measure of how well the parts of a hypothesis fit together.[9] If the different parts count against each other, the hypothesis is less coherent and less likely to be true.
Now consider naturalism and supernaturalism. They are symmetrical claims: naturalism claims that the physical explains the mental, while supernaturalism claims that the mental explains the physical. Both claims are equally modest and equally coherent. Before examining the evidence, both positions are equally likely to be true.[10]
With these definitions in mind, then, I can now defend my second contention. Theism is a type of supernaturalism but could be false even if supernaturalism is true. Furthermore, theism is less modest than either supernaturalism or naturalism. Therefore, before we look at evidence, it is less likely to be true than supernaturalism or naturalism.[11] But that entails that naturalism is intrinsically more probable than theism.

Third Contention

Finally, let’s move onto my third contention: naturalism is a more accurate explanation than theism for many facts.
I’d like to present seven lines of evidence that are red jellybeans, i.e., things more probable on naturalism than on theism.[12]

Physical Matter

(1) Naturalism is the best explanation for the fact that physical reality exists.[13]
If naturalism is true, then physical reality must exist. That’s just part of what naturalism means.
If theism is true, however, things look quite different. The existence of physical reality doesn’t disprove theism; if God exists, God could have created physical space, matter, and energy as part of a plan to create a universe for human beings. But God could have also chosen to create other minds without physical bodies, such as angels. Or God could have chosen to create nothing at all. In other words, God’s existence doesn’t require a physical reality.
So because the physical has to exist on naturalism but does not have to exist on theism, it follows that the existence of physical reality is evidence favoring naturalism over theism.

Success of Science

(2) Naturalism is the best explanation for the fact that science has been so successful without the supernatural.[14]
Imagine a library that contains textbooks for all of the sciences—such as physics, chemistry, and biology—and summarizes current scientific knowledge. The percentage of such knowledge which makes no appeal to the supernatural is extremely high.
Of course, one hears about specific scientific questions which (allegedly) do not have a plausible naturalistic explanation, such as cosmological fine-tuning, the origin of life, and consciousness. But, even if that is or were true, the history of science contains numerous examples of naturalistic explanations replacing supernatural ones and no examples of the reverse. Indeed, naturalistic explanations have been so successful that even most theists concede that supernatural explanations are, in general, unlikely to be true.
Such explanatory success is just what we would expect on naturalism–which entails that all supernatural explanations are false–than it is on theism.[15] And that’s my second line of evidence against theism.

Biological Evolution

(3) Naturalism is the best explanation for the fact that complex life  evolved from simple life.[16]
I’m going to list five scientific facts which support biological evolution. Since Dr. Turek likes acronyms, I’m going to give you the evidence in an acronym, BONES.

  • B is for biogeography;
  • O is for vestigial organs;
  • N is for natural selection;
  • E is for embryology; and
  • S is for stratified fossil record.

Let’s look very briefly at each of these.


First, the evidence indicates that the habitats of plants and animals are distributed in a puzzling way. For example, why are there no land-based mammals on any island more than 300 miles away from the mainland? As University of Chicago biologist Jerry Coyne puts it, “The biogeographic evidence for evolution is now so powerful that I have never seen a creationist book, article, or lecture that has tried to refute it.”[17]

Vestigial Organs

Secondly, a variety of animals have organs which display traits that would be unnecessary if the organs had been designed from scratch, but would have been useful to an ancestor.

Natural Selection

Thirdly, when the genetic differences between living things provides an advantage, things with that advantage tend to be more successful at survival and reproduction than things without that advantage. This is the essence of the process Darwin called natural selection.


Fourthly, as Coyne points out, the evidence indicates that all vertebrate embryos begin development in the same way, looking like embryonic fish, but as they progress, they often go through strange contortions before reaching their final form.[18]

Stratified Fossil Record

Fifthly, the available fossil evidence indicates that as one goes from the oldest to the youngest layers of the fossil record, the layers show gradual change from simple to more complex life forms.
Taken together, the BONES evidence is much more probable on biological evolution (which says that complex life evolved from simple life through trans-generational genetic change)[19] than it is on special creationism (which says that God created all life virtually simultaneously).[20]
If either naturalism or supernaturalism is true, life could exist or not exist. If naturalism is true and life exists, evolution pretty much has to be true. But if theism is true, God didn’t have to use evolution. Furthermore, since theism says that at least one mind existed before any physical matter, it gives a reason to expect that any other minds are fundamentally nonphysical. But that, in turn, leads us to predict conscious life was created independently of nonconscious life, contrary to what evolution claims.[21] So theism predicts that evolution is false.
Thus, the scientific fact of evolution is more likely on naturalism than on theism, and so that’s my third line of evidence against theism.

Pain and Pleasure

(4) Naturalism is the best explanation for the biological role (and moral randomness) of pain and pleasure.[22]
I’m going to give three lines of evidence.
First, moral agents experiencing biologically useful pain and pleasure.
Suppose you are a teenager sleeping in a hotel that has caught on fire. The hotel is old and doesn’t have smoke alarms. The fire gets closer and closer to you until you are actually in pain from the smoke and the intense heat. Your pain wakes you up in time for you to escape; you survive and start a family in your twenties. Your pain in this case was biologically useful because it contributed to your survival. This is just what we would expect on naturalism (and human beings are the products of evolution by natural selection).
Second, moral patients experiencing biologically useful pain and pleasure.
Most human beings are moral agents, people who can be held responsible for their actions and their consequences. But some human beings, such as young children and humans with certain mental disabilities, as well as non-human sentient animals, such as primates and dolphins, are moral patients: sentient beings who can be harmed from their own point of view, but are not responsible for their actions.
On naturalism, we would expect that (biological) sentient beings, including moral patients, would experience pain and pleasure because moral patients are biologically similar to moral agents. On theism, however, we would predict that moral patients do not suffer the same kind of pain as moral agents because such pain plays no known moral role in the lives of the moral patients who experience it.
Third, sentient beings experiencing gratuitous pain and pleasure.
Consider, for example, an animal trapped in a forest fire, suffering horrific pain as it slowly burned to death. On the one hand, this kind of pain is biologically appropriate: it is biologically useful that animals in general feel pain when they come in contact with fire. But, on the other hand, this specific instance of pain was not biologically useful because it did not contribute to the biological goals of survival or reproduction.
On naturalism, this is just what we would expect.  If naturalism is true, all animals are the byproducts of unguided evolution by natural selection, which is both indifferent to suffering and incapable of preventing it.
But if theism is true, God could “fine tune” animals so that they only experience physical pain and pleasure when it was morally necessary. So theism leads us to expect that pain and pleasure are fundamentally moral phenomena, which just happens to be connected to the biological goals of survival and reproduction. That’s a huge coincidence that naturalism doesn’t need.
So this evidence is very much more probable on naturalism than on theism.

Mind-Brain Dependence

(5) Naturalism is the best explanation for the fact that human minds are dependent upon the physical brain.[23]
Philosopher Paul Draper of Purdue University puts it this way: “Consciousness and personality are highly dependent on the brain. Nothing mental happens without something physical happening.”[24] Now Michael Tooley, a philosopher at the University of Colorado at Boulder, has stated five lines of evidence in support of this claim.[25]

  • When an individual’s brain is directly stimulated and put into a certain physical state, this causes the person to have a corresponding experience.
  • Certain injuries to the brain make it impossible for a person to have any mental states at all.
  • Other injuries to the brain destroy various mental capacities. Which capacity is destroyed is tied directly to the particular region of the brain that was damaged.
  • When we examine the mental capacities of animals, they become more complex as their brains become more complex.
  • Within any given species, the development of mental capacities is correlated with the development of neurons in the brain.

Take together, this evidence is much more probable on physicalism, which says that the mind is made only of physical matter, than it is on dualism, which says says that the mind is made of two substances (the physical and the mental). if God exists, God is not in any sense dependent on physical arrangements of matter. So theism entails the existence of at least one unembodied mind. Furthermore, if God wanted to create other minds, he didn’t need them dependent on physical brains.
So the dependence of human minds on brains is evidence against the existence of any being who is supposed to have an unembodied mind, including God. Therefore, the physical nature of minds is evidence favoring naturalism over theism.

Empathy and Apathy

(6) Naturalism is the best explanation for the neurological basis of empathy and apathy, including some moral handicaps.[26]
In many cases, our ability to choose do morally good actions depends upon our having properly functioning emotional capacities, especially empathy, i.e., our ability to identify what someone else is thinking or feeling and to respond to their thoughts and feelings with an appropriate emotion.[27]
We now know, thanks to the relatively new discipline of neuroscience, that certain brain abnormalities cause people to experience less or even no empathy.[28] According to Simon Baron-Cohen of Cambridge University, “There is a consensus in neuroscience that at least ten interconnected brain regions are involved in empathy.”[29] These regions are shown on the slide.
For example, violent psychopaths may know in some abstract sense that their behavior is morally wrong, but utterly lack empathy.[30]
While theism is compatible with a neurological basis for moral handicaps, the fact that at least some moral handicaps can be explained neurologically is much more probable on naturalism than on theism. If theism is true, then that means both 

(a) God creates some human beings with moral handicaps that are not the result of the freely chosen actions of any human being;


(b) These moral handicaps make it more likely that they will harm others.

What moral justification would God have for allowing both (a) and (b) to obtain? This seems utterly surprising and completely random from a theistic, moral point of view, but precisely what we would expect on naturalism (and blind nature is indifferent to the moral consequences of brain abnormalities).[31]

Nonresistant Nonbelief

(7) Naturalism is the best explanation for nonresistant nonbelief (in God).[32]
Imagine you’re growing up in an orphanage and I told you I had met a man who claims to be your father and who really wants a relationship with you. Days, weeks, even months go by but you never actually meet your father. You never get a card, letter, phone call. In fact, the only evidence that your father is alive is my claim that he exists. Why haven’t you heard from him? Perhaps your father is ashamed for abandoning you. Or maybe he’s a prisoner of war and his captors won’t even let him write you. Although you hope your father is alive and wants to meet you, you remain skeptical.
Just as you do not believe your father is alive and wants to meet you, there are people who do not believe that God exists.[33] But notice that, whatever reasons we might invent to explain your earthly father’s absence do not explain their heavenly father’s absence.
At least some of the people who deny God’s existence are “nonresistant” nonbelievers. As philosopher John Schellenberg explains, their nonbelief is “not in any way the result of their own emotional or behavioral opposition towards God or relationship with God or any of the apparent implications of such a relationship.”[34] Such nonbelievers are open to having a relationship with God—in fact, they may even want it—but are unable to have such a relationship. But why, if God exists, does that happen?
On naturalism, blind nature doesn’t care whether anyone believes in God and so the fact of nonresistant nonbelievers is hardly surprising. On theism, however, this fact is very surprising. On theism, we would expect a perfectly loving God to always make a meaningful relationship available to those He loves.


So, in sum, we’ve seen seven lines of evidence that naturalism is true. I also happen to think there is some evidence for theism, but that it is outweighed by the evidence for naturalism.[35] In my other speeches, I will explain why I think this as I respond to Dr. Turek’s arguments.[36]


[1] I owe this definition to Paul Draper.
[2] I owe this definition to Paul Draper.
[3] This definition is similar to, but not identical with, one offered by Paul Draper.
[4] I owe this definition to Paul Draper.
[5] I owe this definition to Paul Draper.
[6] I owe this to Paul Draper.
[7] I owe this jelly bean analogy to Paul Draper. Draper’s full analogy also includes an equal number of yellow jelly beans in both jars, where yellow signifies something that is equally likely to have come from either jar and hence is not evidence that it came from either jar. I have omitted the yellow jelly beans solely in the interest of time.
[8] I owe this definition to Paul Draper.
[9] I owe this definition to Paul Draper.
[10] Paul Draper, “God and the Burden of Proof,” Secular Outpost (July 21, 2014),
[11] Paul Draper, “More Pain and Pleasure: A Reply to Otte” in Christian Faith and the Problem of Evil (ed. Peter van Inwagen, Eerdmans, 2004), 41-54 at 49.
[12] Let N stand for naturalism, T for theism, and F for any of these facts. Using the symbol “Pr(F | H)” to stand for the epistemic probability that F is true conditional upon H, then the claim that some fact is evidence favoring naturalism over theism should be understood as the claim that Pr(F | N) > Pr(F | T).
[13] Jeffery Jay Lowder, “Potential Objections to Swinburne’s Cosmological Argument,” The Secular Outpost (March 17, 2014), Note that here I am using the word “matter” as a way to provide a concrete example of something “physical.”
[14] See Keith M. Parsons, Science, Confirmation, and the Theistic Hypothesis (Ph.D. Dissertation, Kingston, Ontario, Canada: Queen’s University, 1986), 46; Paul Draper, “Evolution and the Problem of Evil” in Philosophy of Religion: An Anthology (3rd ed., ed. Louis Pojman, Wadsworth, 1997), 223-24; and idem, “God, Science, and Naturalism” Oxford Handbook of Philosophy of Religion (ed. William Wainwright, Oxford: Oxford University Press, 2004), 272-303; and Barbara Forrest, “Methodological Naturalism and Philosophical Naturalism: Clarifying the Connection” Philo 3 (2000): 7-29.
[15] Draper 2004.
[16] See Paul Draper, “Evolution and the Problem of Evil” in Philosophy of Religion: An Anthology (3rd ed., ed. Louis Pojman, Wadsworth, 1997), 219-230; cf. Louis P. Pojman, Philosophy of Religion (Mayfield, 2001), chapter 6.
[17] Jerry Coyne, Why Evolution is True (New York: Penguin, 2009), 88.
[18] Coyne 2009, 56.
[19] Draper 1997, 221.
[20] I’m using “virtually simultaneously” as a shorthand way of accounting for the seven literal days described in Genesis 1, in order to contrast that chronology with the sort of geological timescales needed for evolution.
[21] Draper 1997, 224.
[22] Paul Draper, “Pain and Pleasure: An Evidential Problem for Theists.” Nous 23 (June, 1989), 331-350.
[23] Jeffery Jay Lowder, “The Evidential Argument from Physical Minds,” The Secular Outpost (, June 13, 2012.
[24] Paul Draper, “Opening Statement” in William Lane Craig and Paul Draper, Does God Exist? (videotape, West Point, NY, 1996).
[25] Michael Tooley, “Dr. Tooley’s Opening Arguments”  in William Lane Craig and Michael Tooley, The Craig-Tooley Debate: Does God Exist? (, 1994, spotted 25 Jan 99.
[26] Jeffery Jay Lowder, “The Evidential Argument from Physical Minds,” The Secular Outpost (, June 13, 2012.
[27] Simon Baron-Cohen, The Science of Evil: On Empathy and the Origins of Cruelty (New York: Basic Books, 2012), 16.
[28] Baron-Cohen 2012, 39.
[29] Baron-Cohen 2012, 28.
[30] As Baron-Cohen points out, the neurological basis for moral handicaps challenges traditional views about moral responsibility. “If zero degrees of empathy is really a form of neurological disability, to what extent can such an individual who commits a crime be held responsible for what they have done? This gets tangled up with the free will debate, for if zero degrees of empathy leaves an individual to some extent “blind” to the impact of their actions on others’ feelings, then surely they deserve our sympathy rather than punishment.” See Baron-Cohen 2012, 160.
[31] Some theists have pointed out that moral evil, such as fallen angels or demons choosing to do evil, might explain so-called “natural evils.” This argument makes the inverse point: certain natural evils explain at least some moral evil.
[32] J.L. Schellenberg, Divine Hiddenness and Human Reason (Ithaca: Cornell University Press, 1993); idem, 2007.
[33] This sentence, of course, assumes that at least some (if not most) professions of atheism are genuine. Those familiar with intra-Christian debates on apologetic methodologies will notice that I have just ruled out the claim of some (or all?) presuppositionalists, namely, that there are no atheists and instead there are only professed atheists. I agree with  John Schellenberg: “it would take something like willful blindness to fail to affirm that not all nonbelief is the product of willful blindness (even if some of it is).” See J.L. Schellenberg, “What Divine Hiddenness Reveals, or How Weak Theistic Evidence is Strong Atheistic Proof” God or Blind Nature? Philosophers Debate the Evidence (, 2008.
[34] Schellenberg 2008.
[35] It follows from a Bayesian approach to evidence sketched in my first contention that there can be “true evidence” for a false proposition. Consider, for example, people convicted on the basis of eyewitness testimony for crimes they didn’t commit, only to be exonerated years or decades later by DNA evidence. The eyewitness testimony was some evidence for a false proposition (“The defendant is guilty”), but it was greatly outweighed by the DNA evidence against that false proposition. The fact that there can be true evidence for false propositions should serve as a “warning flag” to anyone who wants to claim that there is absolutely no evidence for naturalism (or theism). “There is no evidence for naturalism (or theism)” does not follow from “Naturalism (or theism) is false” or even “I believe naturalism (or theism) is false.”
[36] I am grateful to Paul Draper, John Danaher, Robert Greg Cavin, and Eddie Tabash for helpful comments on a previous version of this speech.

bookmark_borderG&T Rebuttal, Part 5: Chapter 6

Chapter 6. New Life Forms: From the Goo to You via the Zoo?

Drawing upon the work of sophisticated Intelligent Design (ID) theorists such as William Dembski, Michael Behe, and Jonathan Wells, this chapter uses many of the state-of-the art Intelligent Design (ID) arguments against evolution by natural selection. It also defends ID against various objections.
(i) Objections to Natural Selection: G&T argue that macroevolution is defeated by the following objections: (a) genetic limits; (b) cyclical change; (c) irreducible complexity; (d) the nonviability of transitional forms; (e) molecular isolation; and (f) the fossil record.
(a) Regarding genetic limits, G&T repeat the standard creationist claim that there are natural limits to genetic change. In their words:

Unfortunately for Darwinists, genetic limits seem to be built into the basic types. For example, dog breeders always encounter genetic limits when they intelligently attempt to create new breeds of dogs. (142)

This is not a good objection to evolution, however. The dog breeding example is just confused. The whole point of dog breeding is to produce dogs, not new species of dog-like animals. But let that pass. The much more important point is this: G&T, like most creationists, admit that microevolution occurs. If microevolution occurs, then we already have good antecedent reason to expect macroevolution also occurs: macroevolution just is microevolution carried on for a longer period of time. If a species accrues enough “small” changes over time, eventually all of those “small” changes added together become “big” changes and the result is another species. In other words, the difference between microevolution and macroevolution is a difference in degree, not a difference in kind.
(b) Regarding cyclical change, G&T claim that “the changes within types appears to be cyclical.” They take this to be evidence against macroevolution since macroevolution “requires” that changes be “directional toward the development of new life forms” (144). That is a very weak objection to evolution, however.  First, while cyclical change can and does occur, it hardly follows that all evolutionary change is cyclical. Second, contrary to what G&T imply, macroevolution does not require that all evolutionary change is “directional toward the development of new life forms.” If a species lives in a cyclical environment, then evolution predicts the species would display cyclical changes in response to the cyclical environment.
(c) Regarding irreducible complexity, G&T draw upon biochemist Michele Behe’s book, Darwin’s Black Box: The Biochemical Challenge to Evolution.[1] Following Behe, they argue that the cell is an “irreducibly complex system,” i.e., a system that is “composed of several well-matched, interacting parts that contribute to the basic function, wherein the removal of any one of the parts causes the systems to effectively cease functioning” (145). Furthermore, they argue, objections to Behe’s argument, such as those made by biologist Kenneth Miller, are unsuccessful.
Contrary to G&T, however, I don’t think that Behe has successfully shown that there are any irreducibly complex systems. To say that a biological system is “irreducibly complex” assumes that if the system was missing a part, it could not have been functional in any environment forany reason. But a predecessor to that system could lack a part and yet still be functional because some part of its environment is different than the environment of its descendants. In fact, this is precisely what the Darwinian naturalist claims happened. What Behe calls “irreducibly complex systems” evolved indirectly from systems that performed slightly or very different functions in our ancestors. In order to justify his claim that a system is irreducibly complex, Behe must show that precursors could not have performed different functions in those ancestors. Behe hasn’t shown this.[2]
(d) Regarding the viability of transitional forms, G&T argue that transitional forms could not survive.

For example, consider the Darwinian assertion that birds evolved gradually from reptiles over long periods of time. This would necessitate a transition from scales to feathers. How could a creature survive that no longer has scales but does not quite have feathers? Feathers are irreducibly complex. (148)

The question, “How could a creature survive that no longer has scales but does not quite have feathers?”, is just that: a question, not an argument.  This question can give the illusion of having refuted the possibility of transitional forms only by ignoring the relevant scientific evidence available at the time I Don’t Have Enough Faith was written: (1) the 1861 discovery of a reptile-bird Archaeopteryx, which had both feathers and reptilian features (such as teeth, claws, and a long, bony tail); and (2) the 1996 discovery of Sinosauropteryx, which had evidence of primitive feathers (“a layer of thin, hollow filaments covering its back and tail”).[3] Additionally, since the publication of the book, we may add (3) the 2009 discovery of Tianyulong, a small dinosaur with hairlike “feathers,” which some scientists believe is evidence that all dinosaurs may have had hairy or feathery bodies.[4] The fact that such creatures existed refutes the idea that such creatures could not survive.
Regarding the claim that “feathers are irreducibly complex,” G&T provide no argument to justify that claim, but it’s not hard to imagine what such an argument would look like. For example, such an argument might appeal to two claims: (1) reptile-bird transitional forms could not use their less-than-fully developed feathers (“proto-feathers”) for flight; and (2) reptile-bird transitional forms could not have used their proto-feathers for other functions (besides flight). The second claim is false. Scientists have no problem identifying other uses for proto-feathers, including insulation and sexual selection,[5] and G&T provide no reason at all to reject such explanations. But this entails that G&T have not shown that such indirect routes for the evolution of modern feathers are improbable.
(e) Regarding molecular Isolation, G&T appeal to Michael Denton ‘s 1986 book, Evolution: A Theory in Crisis.[6] Commenting on Denton’s work, they write:

If all species share a common ancestor, we should expect to find protein sequences that are transitional from, say, fish to amphibian, or from reptile to mammal. But that’s not what we find at all. (150)

In his review of Denton’s book, however, Philip Spieth, a geneticist at the University of California at Berkeley, argues that Denton’s conclusions are erroneous. It is worth quoting Spieth at length:

These conclusions are erroneous: in his interpretation of “molecular equidistance,” Denton has confused ancestor-descendant relationships with cousin relationships. The telltale clues of molecular data are not, directly, concerned with parents and offspring, intermediate forms, and “missing links.” They are, instead, reflections of relative relatedness between contemporary cousins. Twentieth-century bacteria are not ancestors of twentieth-century turtles and dogs: they are very distant cousins, and, as the data in Denton’s presentation show, the bacteria are roughly equally distant cousins of both turtles and dogs (and all the other organisms that Denton included in Table 12.1).
Cousin relationships between contemporary individuals are governed by the number of generations since there last was an ancestor in common to the individuals. Different members of a group of close relatives always have the same relationship to a more distantly related individual who stands outside the group. Two sisters are equally related to a mutual first cousin. Members of a group of siblings and first cousins are all equally related to a mutual fifth cousin. Lampreys are equally distant cousins of both fish and humans because the last ancestor that lampreys had in common with humans was the same ancestor lampreys had in common with fish. The “molecular equidistance” argument that Denton invokes is invalid, resulting from making comparisons between a single distantly related organism and various members of a more closely related group.
There is an irony in Denton’s presentation to anyone familiar with the data of molecular evolution. Reflections of genealogical relationships are so strong in molecular data that Denton, in spite of his arguments to the contrary, is unable to hide them. The missing “trace” of which he speaks is not a trace; it is a shout. Simple inspection of the data in Table 12.1 will reveal that cytochrome C found in horses, for example, is quite similar in its molecular structure to that found in turtles, slightly less similar to that in fish, still less similar to that in insects, and very much less similar to that in bacteria. The traditional evolutionary series is very much in evidence.
Denton provides a series of diagrams (pp. 282-87) in which nested e[l]lipses, arranged on the basis of molecular data, are used to illustrate his spurious “molecular equidistance” thesis. In these delightful figures organisms are seen to cluster fully in accord with the genealogical relationships that evolutionary biologists deduced from comparative anatomy and paleontological evidence long before molecular data were available. In the final figure, humans and chimps are seen side by side as each other’s closest cousin. Anyone who wants to argue that these nested groups of organisms constitute separate, distinct, and unbridg[e]able groups has to contend with obvious hierarchical patterns of relatedness among the various groups. Notions of relatedness are, of course, antithetical to a typological view of organisms.[7]

(f) Regarding the fossil Record,G&T make three points: (1) gradualism predicts that we should find “thousands, if not millions, of transitional fossils by now,” but that prediction is false; (2) the so-called “Cambrian explosion” is inconsistent with Darwinism because “nearly all of the major groups animals known to exist appear in the fossil record abruptly…, fully formed, and at the same time;” and (3) the fossil record cannot establish ancestral relationships.
I shall argue that each objection is unsuccessful.
(1) is an argument from silence. Given the enormous popularity of this argument (hereafter, “the missing links argument”) in the anti-evolution literature, it is worth showing in detail that it is not successful.
As I have pointed out elsewhere, arguments from silence are a special version of a type of inductive argument known as an explanatory argument. If we let be our background information; S be some truth about the silence of a potential source of evidence; H1 and H2 be rival explanations; Pr(x) be the epistemic probability of some proposition x;[8] and Pr(x | y) be the epistemic probability of x conditional upon y, then we can define arguments from silence according to the following argument schema.

(1) S is known to be true, i.e., Pr(S) is close to 1.
(2) The prior probability of H1 is not much greater than H2, i.e., Pr(H1 | B) is not much greater than Pr(H2 | B).
(3) H2 gives us more reason to expect S than H1, i.e., Pr(S | H2) > Pr(S | H1).
(4) Other evidence held equal, H1 is probably false, i.e., Pr(H1 | B & S) < 1/2.

Like any other explanatory argument, an argument from silence can be logically correct if there is good reason to believe that premises (1)-(3) are true.
With this schema in place, let’s return to the missing links argument. If we abbreviate “the fossil record does not contain any transitional fossils” as S and let E represent evolution, then the missing links argument can be summarized as follows.

(1′) S is known to be true, i.e., Pr(S) is close to 1.
(2′) E is not intrinsically much more probable than ~E.
(3′) ~E gives us more reason to expect S than E, i.e., Pr(S | ~E) > Pr(S | E).
(4′) Other evidence held equal, E is probably false, i.e., Pr(E | B & S) < 1/2.

In support of the first premise, G&T use another type of inductive argument, the argument from authority. Their authority is the late paleontologist Stephen Jay Gould; they claim he agrees with S on the basis of the following quotation.

The history of most fossil species includes two features particularly inconsistent with gradualism: 1). Stasis. Most species exhibit no directional change during their tenure on earth. They appear in the fossil record looking much the same as when they appear; Morphological change is usually limited and directionless. 2). Sudden Appearance. In any local area, a species does not arise gradually by the steady transformation of its ancestors; it appears all at once and ‘fully formed.'[9]

Commenting on this quotation, G&T conclude, “In other words, Gould is admitting that fossil types appear suddenly, fully formed, and remain the same until extinction without any directional change…” (152). We shall abbreviate this conclusion as P.
The most charitable formulation of this argument from authority would be to formulate it as a special version of the inductive argument form known as the statistical syllogism.[10]

(5) The vast majority of statements made by Stephen Jay Gould concerning the fossil record are true.
(6) P is a statement made by Stephen Jay Gould concerning the fossil record.
(7) Therefore, P is true.

While some arguments from authority are inductively correct, this one is not. A careful reading of the Gould quotation does not support G&T’s interpretation. Gould wrote, “The history of most fossil species …,” not, “The history of all fossil species…” This basic distinction is crucial to a correct understanding of Gould’s point (and punctuated equilibrium in general), but anti-evolutionists often fail to recognize it. Indeed, Gould himself repeatedly stated that critics of evolution were quoting him out of context. In 1984, Gould wrote, “It is infuriating to be quoted again and again–whether through design or stupidity, I do not know–as admitting that the fossil record includes no transitional forms.”[11] He continued, “Transitional forms are generally lacking at the species level, but they are abundant between larger groups.”[12] Note that Gould does not say that transitional forms are completely lacking at the species level, only that they are generally lacking. More recently, in 1994 Gould gave a specific example of a transitional sequence in the fossil record:

I am absolutely delighted to report that our usually recalcitrant fossil record has come through in exemplary fashion. During the past 15 years, new discoveries in Africa and Pakistan have added greatly to our paleontological knowledge of the earliest history of whales. The embarrassment of past absence has been replaced by a bounty of new evidence– and by the sweetest series of transitional forms an evolutionist can find. Truly, we have met the enemy and he is now ours. Moreover, to add blessed insult to the creationists’ injury, these discoveries have arrived in a gradual and sequential fashion– a little bit at a time, step by step, from a tentative hint, 15 years ago to a remarkable smoking gun early in 1994.[13]

It is a misuse of arguments from authority to misquote or misinterpret an authority.[14] Since G&T have misquoted or misinterpreted Gould, their argument from authority is fallacious. It does not support (1’).
But G&T have an independent supporting argument for (1’). Citing molecular biologist Jonathan Wells,[15] G&T also appeal to the so-called Cambrian “explosion” in support of (1’). In their words,

… nearly all of the major groups of animals known to exist appear in the fossil record abruptly and fully formed in strata from the Cambrian period (which many scientists estimate to have occurred between 600 and 500 million years ago). (152)

Again, G&T do not provide the logical form of their argument, so, again, I will offer what I believe to be the most charitable formulation. Let RC be the reference class of “the major groups of animals known to exist” and AC be the attribute class of “appear in the fossil record abruptly and fully formed in strata from the Cambrian period.” Then we can formulate the argument in the above quotation as an inductive argument type known as the statistical generalization.[16]

(8) Nearly all of the observed members of RC are AC.
(9) Therefore, nearly all RC are AC.

I have four replies.
First, the name Cambrian “explosion” is misleading insofar as it suggests to popular audiences—who are not used to thinking in geological timescales (i.e., tens to thousands of millions of years)—that there was a single event. In fact, this “explosion” represents a series of events over the course of 15 -20 million years. Alan Gishlick explains:

The Cambrian Explosion is, rather, the preservation of a series of faunas that occur over a 15-20 million year period starting around 535 million years ago (MA). A fauna is a group of organisms that live together and interact as an ecosystem; in paleontology, “fauna” refers to a group of organisms that are fossilized together because they lived together.[17]

Second, the fact—if it is a fact—that there are no known Cambrian transitional fossils is compatible with the existence of other, later transitional fossils. In other words, even if there are no known transitional fossils which can be dated between 600 and 500 million years ago, it doesn’t follow that there are no later transitional fossils, i.e., fossils which can be dated between 500 million years ago and the present. In fact, the fossil record does contain numerous transitional forms, forms which G&T do not acknowledge, much less refute, in their book.[18]
Third, as written, this statement is false: “most of the major groups of animals known to exist” do not appear in the fossil record in strata from the Cambrian period. Amphibians, reptiles, birds, and mammals do not appear in the fossil record until very much later than the Cambrian period, just as evolution predicts. The most charitable interpretation I can give to G&T’s statement is to assume that it is a typo. Instead of “nearly all of the major groups of animals known to exist,” I assume that what G&T meant to write is “nearly all of the animal body plans known to exist.” Thus, we should revise RC as follows:

RC’: the reference class of “the animal body plans known to exist”

And the revised statistical generalization becomes:

(8’) Nearly all of the observed members of RC’ are AC.
(9’) Therefore, nearly all RC’ are AC.

I take this revised statistical generalization to be charitable, since it would make G&T’s point consistent with the recent, published work of Stephen Meyer, another leading ID theorist.[19]
Fourth, even (8’) is false. As Gishlick points out, many of the Cambrian body plans—including those of cnidrians, molluscs, sponges, wormlike metazoans, bilateral animals, and possibly arthropods—do not appear “abruptly.” We have fossilized remains of their precursors from fossils dating 10-60 million years older than their Cambrian descendants. As Gishlick explains:

Sixty million years is approximately the same amount of time that has elapsed since the extinction of non-avian dinosaurs, providing plenty of time for evolution. In treating the Cambrian Explosion as a single event preceded by nothing, Wells misrepresents fact – the Cambrian explosion is not a single event, nor is it instantaneous and lacking in any precursors.[20]

The upshot is that both supporting arguments for (1’) fail. Thus, G&T have not given any good reasons to think (1’) is true. Furthermore, again, there is very good reason to think (1’) is false, namely, all of the fossilized intermediate and transitional forms, including reptile-birds, reptile-mammals, ape-humans, legged whales, and legged seacows.[21]
Let’s move onto the missing link argument’s premise (3’). G&T write:

If Darwinism were true, we would have found thousands, if not millions, of transitional fossils by now. (2770-2771)

Since it is implied that if Darwinism is false, we would not expect to find transitional fossils, it seems reasonable to interpret G&T as asserting (3’). For convenience, here it is again.

(3′) ~E gives us more reason to expect S than E, i.e., Pr(S | ~E) > Pr(S | E).

As it stands, however, (3’) is not obviously true. By itself, evolution doesn’t predict how many transitional fossils we would find today. Rather, by itself, evolution predicts that there were “thousands, of not millions,” of transitional forms, i.e. living beings. After a living being dies, its remains may or may not be destroyed (such as being eaten by other animals or by decay). If its remains are not destroyed, the remains may or may not become fossilized. If a dead organism is fossilized, that fossil may or may not survive intact to the present day. If the fossil survives intact to the present day, that fossil may or may not be found. If the fossil is found, it may or may not have preserved enough information to determine whether it is transitional. If the fossil preserves enough information to identify it as transitional, it may or may not have been examined yet by someone knowledgeable enough to identify it as such.[22]
The hypothesis of evolution says nothing about any of this. We get predictions about the number of transitional fossils only when we combine evolution with one or more auxiliary hypotheses about the frequency of fossilization, fossil preservation, fossil discovery, and fossil classification. G&T do not defend any of these auxiliary hypotheses and so their case for (3′) is, at best, incomplete.
So why should we believe (3’) is true? According to G&T, the answer is “because Darwin said so.”

… [Charles Darwin] did recognize that the fossil record posed a big problem for his theory because it didn’t show gradualism. That’s why he wrote, “Why then is not every geological formation and every stratum full of such intermediate links? Geology assuredly does not reveal any such finely graduated organic chain, and this, perhaps, is the most obvious and gravest objection which can be urged against my theory.”(152)

There is little doubt that G&T’s quotation of Darwin has great rhetorical value; it is analogous to the courtroom strategy of obtaining testimony from a hostile witness. What this quotation has in rhetorical value, it lacks in logical or evidential value.  Once again G&T making an argument from authority and, once again, the argument is logically incorrect because G&T have quotemined that authority.
The quotation appears in Darwin’s Origin of Species, sixth edition, in chapter 10, “On the Imperfection of the Geological Record.” As Jon Barber points out, “Darwin’s writing style was to ask a rhetorical question and then give an answer.”[23]  In order to show Darwin’s tendency “in action,” I’m going to quote a longer excerpt of the book than G&T did, with the portion quoted by G&T in italics.

But just in proportion as this process of extermination has acted on an enormous scale, so must the number of intermediate varieties, which have formerly existed, be truly enormous. Why then is not every geological formation and every stratum full of such intermediate links? Geology assuredly does not reveal any such finely graduated organic chain; and this, perhaps, is the most obvious and serious objection which can be urged against my theory. The explanation lies, as I believe, in the extreme imperfection of the geological record.
In the first place, it should always be borne in mind what sort of intermediate forms must, on the theory, have formerly existed. I have found it difficult, when looking at any two species, to avoid picturing to myself forms DIRECTLY intermediate between them. But this is a wholly false view; we should always look for forms intermediate between each species and a common but unknown progenitor; and the progenitor will generally have differed in some respects from all its modified descendants. To give a simple illustration: the fantail and pouter pigeons are both descended from the rock-pigeon; if we possessed all the intermediate varieties which have ever existed, we should have an extremely close series between both and the rock-pigeon; but we should have no varieties directly intermediate between the fantail and pouter; none, for instance, combining a tail somewhat expanded with a crop somewhat enlarged, the characteristic features of these two breeds. These two breeds, moreover, have become so much modified, that, if we had no historical or indirect evidence regarding their origin, it would not have been possible to have determined from a mere comparison of their structure with that of the rock-pigeon, C. livia, whether they had descended from this species or from some other allied species, such as C. oenas.
So with natural species, if we look to forms very distinct, for instance to the horse and tapir, we have no reason to suppose that links directly intermediate between them ever existed, but between each and an unknown common parent. The common parent will have had in its whole organisation much general resemblance to the tapir and to the horse; but in some points of structure may have differed considerably from both, even perhaps more than they differ from each other. Hence, in all such cases, we should be unable to recognise the parent-form of any two or more species, even if we closely compared the structure of the parent with that of its modified descendants, unless at the same time we had a nearly perfect chain of the intermediate links. (boldface mine)

The extended passage, especially the sentence I’ve boldfaced  above, exposes the inaccuracy in G&T’s selective quotation of Darwin. Not only does the extended passage fail to support (3’); it provides clear and decisive evidence against it. Furthermore, Darwin’s explanation also directly refutes the familiar creationist claim, parroted by G&T, that “All animal groups appear separately, fully formed, and at the same time” (###).
G&T also object to the fossil record as evidence for evolution for another reason. Following Michael Denton and Jonathan Wells, G&T argue that “the fossil record cannot establish ancestral relationships” (###).  As Mark Vuletic has argued, however, Denton relies upon “unreasonably strict criteria” for recognizing transitional forms. I will quote Vuletic at length.

Now to the fossil record. Similar to the creationists, Denton proposes that there are not enough transitional forms in the fossil record, and that what transitional forms do exist are rather dubious in nature because they do not show soft organ changes (since organs aren’t fossilized) and are not intermediate in every single characteristic. Thus, Archaeopteryx lithographica, perhaps the most famous transitional form of all time, is inadequate because its wings and feathers were fully formed. Never mind that Archaeopteryx sported more reptilian skeletal characteristics than it did avian ones, and ignore the fact that its skeletal characteristics very closely match a class of wingless reptiles called therodonts that existed around the same time and in the same geographical location. It is apparent, then, that Denton’s standards for labeling a fossil a “transitional form” are unreasonably restrictive.
As far as soft organ characteristics go, researchers can indeed also obtain information on a fossilized organism’s soft anatomy and behavior by paying attention to structural characteristics. Thus, the recent find of Ambulocetus natans (Berta, 1994) lends further credence to the ungulate-to-whale transition that Denton finds so incredulous, because the skeletal arrangement of the creature is such that it could undulate its spine to produce a motion not unlike that of the whale’s tail motion (not to mention that Ambulocetus was found geographically and temporally just about where evolutionists hoped to find it). Similarly, examination of the configuration of basal ridges in fossilized reptile-mammal transitional form skulls shows how endothermy developed gradually, even though the evolution of the soft, complex endothermic apparatus could not be directly observed (Hillenius, 1994).
Denton’s denial of the fish-to-amphibian transition as demonstrated by Eusthenopteron (a late Devonian fish) and Icthyostega (a late Devonian amphibian) is a striking example of the excessive demands he makes on transitional forms. He echoes creationist Duane Gish’s criticism that Icthyostega has well developed limbs for terrestrial movement, while Eusthenopteron has mere fins. In the first place, it is unreasonable to expect a transitional form to be transitional in every single skeletal characteristic it exhibits. Secondly, the correlation between the skull and vertebral characteristics of the two creatures is impossible to account for in a framework of typology:
The crossopterygian fish Eusthenopteron is linked to the early amphibian Icthyostega by a number of characteristics: (1) same pattern of skull bones as Icthyostega, (2) internal nostrils (found only in land animals and sarcopterygians – a taxonomic group encompassing lungfish and crossopterygians), (3) teeth like amphibians’, (4) a two-part cranium (icthyostegids are the only other vertebrates that have this characteristic), and (5) same vertebral structure. (derived from McGowan, 1984, 152-153)
Every once in a while, a new transitional form turns up and strengthens the evolutionary pattern inherent in the fossil record . But in any case, to deny that the ones that already exist are what they appear to be is a sure indication of unreasonably strict criteria for transitional forms.[24]

In summary, then, all of G&T’s objections to biological evolution fail.

Rebuttal to Geisler’s and Turek’s “I Don’t Have Enough Faith to be an Atheist”

[1] Michael J. Behe, Darwin’s Black Box: The Biochemical Challenge to Evolution (New York: Free Press, 1996).
[2] Paul Draper, “Irreducible Complexity and Darwinian Gradualism: a Reply to Michael J. Behe,” Faith and Philosophy 22 (2002), 3–21.
[3] Carl Zimmer, “Evolution of Feathers: The Long Curious Extravagant Evolution of Feathers,” National Geographic  (February 2011). Republished electronically at
[4] Zimmer 2011.
[5] Zimmer 2011.
[6] Michael Denton, Evolution: A Theory in Crisis (Chevy Chase, Maryland: Adler & Adler, 1986).
[7] Philip T. Spieth, “Review: “Evolution — A Theory in Crisis” Zygon 22 (1987), 249-68. doi:10.1111/j.1467-9744.1987.tb00849.x. Republished electronically at
[8] By “epistemic probability,” I mean this. “Relative to K, p is epistemically more probable than q, where K is an epistemic situation and p and q are propositions, just in case any fully rational person in K would have a higher degree of belief in p than in q.” See Paul Draper, “Pain and Pleasure” in The Evidential Argument from Evil (ed. by Daniel Howard-Snyder, Bloomington, IN: Indiana University Press, 1996), 27.
[9] Stephen J. Gould, “Evolution’s Erratic Pace,” Natural History 86 (1977): 13-14, quoted in G&T 2004, 152.
[10] See Wesley C. Salmon, Logic (third ed., Englewood Cliffs: Prentice-Hall, 1984), 98.
[11] Stephen Jay Gould, Hens Teeth and Horse’s Toes (New York: Norton & Co., 1983), 260. Reprinted in “Evolution as Fact and Theory” in Science and Creationism (ed. Ashley Montagu, New York: Oxford University Press, 1984), 123-24. Italics are mine.
[12] Gould 1983, 261.
[13] Stephen Jay Gould, “Hooking Leviathan by its Past” Natural History 5/94, 11.
[14] Salmon 1984, 98.
[15] Jonathan Wells, Icons of Evolution: Science or Myth?: Why Much of What We Teach About Evolution Is Wrong (Washington, D.C.: Regnery, 2000).
[16] Salmon 1984, 90.
[17] Alan Gishlick, “Icons of Evolution? Why Much of What Jonathan Wells Writes About Evolution is Wrong” National Center for Science Education (October 23, 2008),, 11-12.
[18] See L. Beverly Halstead, “Evolution–The Fossils Say Yes!” Science and Creationism (ed. Ashley Montagu, New York: Oxford University Press, 1984), 240-254; Roger J. Cuffey, “Paleontologic Evidence and Organic Evolution” Science and Creationism (ed. Ashley Montagu, New York: Oxford University Press, 1984), 255-281; Laurie R. Godfrey, “Creationism and Gaps in the Fossil Record” Scientists Confront Creationism (ed. Laurie R. Godfrey, New York: W.W. Norton & Company, 1983), 193-218.
[19] Meyer argues that Cambrian animal forms contain “functionally specified information” and so are irreducibly complex systems; moreover, this morphological irreducible complexity is independent of the sort of biochemical irreducible complexity argued by Behe. Meyer’s argument, however, fails for the following reasons. (i) Even if the origin of Cambrian animal forms were evidence favoring ID over naturalism, at best Meyer’s argument commits the fallacy of understated evidence. Meyer neglects to mention other known facts about Cambrian animal forms, facts which favor naturalism over ID. For example, (a) the Cambrian era did not include animal forms much more impressive than known Cambrian forms; (b) the creation of new information is habitually associated with embodied minds; and (c) all living animals on Earth are the gradually modified descendants of Cambrian animals. (ii) According to Meyer, an unknown Intelligent Designer used an unknown, mysterious mechanism to design Cambrian animal forms for an unknown purpose. It follows, therefore, that Meyer’s intelligent design “hypothesis” is, at best, an explanation name, not an actual explanation, because the Intelligent Designer’s methods and purposes are unknown and, indeed, mysterious. As philosopher Paul Draper pointed out (in an unrelated context), “Mystification is the opposite of explanation.” See Stephen L. Meyer, Darwin’s Doubt: The Explosive Origin of Animal Life (New York: Harper One, 2013); and Paul Draper, “A Darwinian Argument from Evil,” unpublished paper. Cf. Gregory W. Dawes, Theism and Explanation (New York: Routledge, 2009).
[20] Gishlick 2008, 13.
[21] See Douglas Theobald, “29+ Evidences for Macroevolution: Part 1: The Unique Universal Phylogenetic Tree,” The TalkOrigins Archive (2013),
[22] Mark Isaak, “Index to Creationist Claims: Claim CC200.1” The TalkOrigins Archive (2005),
[23] See Jon Barber, “Quote #75” in The Quote Mine Project: Or Lies, Damned Lies, and Quote Mines at The Talk.Origins Archive (2003-2004),
[24] Mark I. Vuletic, “Review of Michael Denton’s Evolution: A Theory in Crisis,” The Talk.Origins Archive (1996-97),