Creation and Evolution (Part 15)

July 30, 2013     Time: 00:30:51

Last time we talked about the compatibility of evolutionary theory with Christian theism. I argued that, in fact, evolutionary theorists, when you press them for what the theory technically holds, does not hold that life or biological complexity on this planet originated by chance. Rather, randomness in the theory simply means that the mutations occur without a view toward the benefit of the organism in which they occur. So the theory is entirely compatible with God having a purpose or a direction or even causal influence upon the evolutionary process.

Methodological Naturalism

This raises a related question. Many scientists and philosophers would argue that science, by its very nature, is committed to a sort of methodological naturalism. Not a metaphysical naturalism, according to which supernatural entities do not exist, but simply a methodological form of naturalism. That is to say, science seeks only natural causes of the phenomena in the world. It is part of the methodology of science to simply look for natural causes of the phenomena that it investigates. Therefore, supernatural explanations of phenomena would simply be methodologically excluded from the pool of live explanatory options. So, if we had a body of empirical data to be explained, the natural scientist will assemble a pool of live explanatory options to choose from and methodologically he would include in this pool of live explanatory options only hypotheses that are appealing to purely natural causes. That is not to say that there are not non-natural or supernatural entities that exist that might provide other sorts of explanations but simply that methodologically these don’t enter into the project of science. The project of science is to find the best natural explanation of the phenomena that it seeks to explain. So these supernaturalistic hypotheses wouldn’t even come into consideration – they are not even in the pool of live explanatory options. This would hold for the Christian scientist as well. The Christian scientist must be methodologically restricted to naturalistic explanations.

What is striking about methodological naturalism is that it is a philosophical, and not a scientific, viewpoint. This is not an issue to which scientific evidence is relevant. Rather, it is about the philosophy of science. It is about the limits of science and the nature of the project of science and what science is restricted to. So this is not something that is susceptible to scientific proof or disproof. It is a philosophical question about the nature of science as such. As a philosophical question, it is extremely difficult to justify methodological naturalism. As William Dembski has pointed out, adopting methodological naturalism would prevent your inferring design of the universe even if every atom in the universe were inscribed with the label “Made by God” on it, which would seem preposterous. More seriously, suppose that life and biological complexity really were the result of creative miraculous interventions at various points in the past? Suppose we really do live in a universe like that – where God has miraculously intervened in the evolutionary process to bring about life forms that would not have otherwise evolved.[1] It would be a tragedy, don’t you think, if we were prevented from discovering the truth about reality simply because of a methodological constraint that we have adopted. This would be, I think, a tragedy not only personally but scientifically as well. We would be prevented from really knowing the truth about how life and biological complexity came about simply because of this methodological constraint that we’ve adopted. Methodology is supposed to be an aide to helping you discover the truth about reality, not to be a hindrance keeping you from discovering the truth about reality.

But, let’s leave that point aside. The more important point that I want to make is that we are not now, in this context, concerned with what a scientist as a scientist might infer is the best explanation of biological complexity. That is not the question that we are raising in this class – what a scientist as a scientist is at liberty to infer about the best explanation of biological complexity. Rather, our question that we are exploring is, “How, from a theological point of view, should we integrate what the Bible teaches with what the best scientific evidence indicates?” We are not trying to justify an inference to design. Rather, we are taking a theological standpoint – beginning with what the Bible teaches – and we are trying to integrate our theology with the empirical evidence. So even if it is true that the scientist can only work within the constraints of methodological naturalism, that doesn’t affect in any way the systematic theologian. The systematic theologian is quite at liberty to adopt non-naturalistic views of the world if those help to integrate theology and science in a more harmonious way.

It seems to me that the systematic theologian who approaches this question could admit freely that, say, the neo-Darwinian theory of evolution is in fact the best naturalistic hypothesis for explaining biological complexity. He could say that of the naturalistic options available, the neo-Darwinian theory is by far the best naturalistic theory we’ve got. If, as a result of methodological naturalism, we are constrained to looking only at naturalistic hypotheses then, until recently at least, it does seem that the neo-Darwinian theory of biological evolution which explains evolutionary development in terms of random mutation and natural selection is in fact the best naturalistic theory. Indeed, really, as we’ve said before, it is the only game in town pretty much. The rival naturalistic hypotheses cannot equal the explanatory power, the explanatory scope, and the plausibility of the neo-Darwinian hypothesis. So, one could agree that the best naturalistic account is the neo-Darwinian theory. No matter how improbable it seems relative to the evidence, no matter how enormously far its explanatory mechanisms need to be extrapolated beyond the testable evidence, and no matter the lack of evidence for many of its key tenets, nevertheless, it is still the best naturalistic explanation compared to its rivals because there isn’t any other naturalistic explanation that comes close to the standard theory in terms of its explanatory virtues.

Phillip Johnson[2], for example, has often said that he would have no objection at all to evolutionary theorists saying that neo-Darwinian evolutionary theory is the best naturalistic explanation we have of biological complexity.[3] He has no objection to a claim like that at all – that of the pool of live explanatory naturalistic options, the neo-Darwinian theory is the best. But, what Johnson objects to is saying that the neo-Darwinian evolutionary theory is the best explanation period. When you consider the non-naturalistic explanations, Johnson would contend that, if you were to include them in the pool of live explanatory options, then it would no longer be obvious that the best explanatory option is the neo-Darwinian theory. He would say then some of these supernaturalistic hypotheses may well be better.

What we are going to do in this class is we are going to approach this question from a theological point of view. We are going to ask, given the biblical data and the scientific evidence, how should we best understand the origin of life and the origin of biological complexity? As we approach these questions I want to emphasize that I am not a professional biologist. Rather, I am a theologian with a layman’s interest in these scientific questions. So I do not speak with expertise on these biological questions, but like you have a layman’s interest in them and want to do the best job I can of synthesizing my theology with what the best scientific evidence today indicates.


Question: Basically, you are talking about evidences and you have used that term of evidence but is it not also possible that there can be a bias in the collection of evidence and the presentation of evidence? We, as philosophers looking at this, have sort of an assumption that the evidence that is being accepted is true evidence properly presented. I am not saying it is not – what percentages we don’t know – but that caveat should be understood from the very beginning that not all evidence is really true evidence. It is biased by the collector.

Answer: I think that is a fair comment and it is true that sometimes people who are scientific mavericks get excluded from the mainstream discussion because they disagree and they look at anomalous data that doesn’t fit. But I must say in all honesty, I think one of the wonderful things about science is its self-correcting nature. It is true that these kinds of things happen but what you find, I think, is over a generation or so the anomalies surface and come back and subsequent scientists come to see the biases and the prejudices that blinded earlier thinkers and that evidence has to be freshly dealt with again. So these anomalies I don’t think can be suppressed forever. Science really does have a wonderful kind of self-correcting feature to it that makes it hard for the evidence to be perpetually twisted and distorted in such a way that it can’t be seen correctly. But certainly those who are going against, say, a mainstream view will need to exhibit courage and tenacity in demanding that their data be looked at and that the scientific paradigm, the mainstream view, look honestly at this anomalous data that they are presenting. I think that is right.

Question: I would be curious how you would respond to one of the most common defenses of scientific naturalism, which is that it seems to work. You will often here people comment that physics and chemistry has been so successful in describing the world around us that scientific naturalism must be the right way to go because it has been successful.[4]

Answer: This is exactly the defense that Alex Rosenberg, whom I am going to be debating at Purdue[5], takes in justification of what he calls scientism, or as you put it, scientific naturalism.[6] What I want to say about this is that this term covers a diversity of viewpoints that need to be carefully distinguished if we are not to be misled. First, there is what we can call epistemological naturalism. What is that? Well, epistemological naturalism says that we should only believe what can be scientifically proven; science is our only source of knowledge and truth. That is epistemological naturalism. Metaphysical naturalism, on the other hand, is the view that only physical things exist. There are no supernatural realities like spirits, souls, God, and so forth. So we have epistemological naturalism which says science is the only source of knowledge and truth and metaphysical naturalism which says that only physical things exist and there are no supernatural entities.

With regard to epistemological naturalism, the justification would be the success of natural science in giving us truth about the world. It has been enormously successful in telling us what the physical world is like. What I would say to that is that that goes no distance whatsoever in showing that science is the only source of knowledge and truth. What it does is show that natural science is the best way of discovering truth about the physical world. It is what will give us knowledge of the physical world. But to say that, therefore, there are no ethical truths, there are no aesthetic truths, there are no mathematical or logical truths, and there are no metaphysical truths (like that the past has existed longer than 5 minutes or that the external world is real) would be, I think, an overly restricted theory of truth and knowledge. We can know things even though they can’t be scientifically proven. And, indeed, this kind of epistemological naturalism would actually undermine science itself because science is, itself, permeated by assumptions that cannot be scientifically proven. So if you adopt this view, it would in fact undermine the very project of science.

What I think we want to say is that the incredible, amazing track record of empirical science simply shows that science is the best tool for knowledge and truth about the physical universe but it doesn’t imply that there are other types of truth. The philosopher Ed Feser gives a wonderful analogy.[7] He says imagine you have a metal detector which is so calibrated that it will detect anything metal – it is so infallible that it is the best metal detector you could find. He asks, “Would that prove that there are no non-metallic objects? That the only things that exists are metallic things?” Well, obviously not. And that is exactly the same error that the epistemological naturalist is making. Because his metal detector, so to speak, is so good and so efficient at discovering empirical physical truth he concludes there is no other kind of truth and that there is no other source of knowledge. That is as silly as the person who thinks the metal detector would show there are no non-metallic objects. That would be epistemological naturalism.

I would also say that epistemological naturalism is self-defeating because the statement “science is the only source of knowledge” is something that cannot be scientifically proven. That is a philosophical statement. If you only believe what science could prove then you would not believe that statement. Therefore epistemological naturalism is really self-refuting.

What I want to say in addition to that is, with respect to metaphysical naturalism, even if you were an epistemological naturalist, that doesn’t imply metaphysical naturalism because I think you can have arguments that appeal to modern science for positing non-physical realities.[8] A paradigm example of this was the Harvard philosopher W. V. O. Quine who was the most famous epistemological naturalist of the 20th century. Quine said we should only believe what the natural sciences discover and teach us. Nevertheless, Quine showed himself remarkably and commendably open to the existence of non-physical, immaterial entities. He said if you could show him the indirect explanatory benefit of soul, of a creator, he said he would joyfully accord to them scientific status along with quarks and black holes.[9] As you know, many of the arguments that I use for God’s existence, like the arguments for the origin of the universe and the fine-tuning of the universe, precisely follow Quine’s prescription. They try to show the explanatory benefit of theism with regard to scientifically established facts like the origin and fine-tuning of the universe. In fact, Quine himself actually did believe in the existence of non-physical, immaterial entities. In particular, he thought that modern science requires us to believe in the existence of mathematical objects like sets and that these must also be part of our view of what actually exists. So Quine himself was not a metaphysical naturalist in that sense. He believed that in addition to physical entities, there are these non-physical, mathematical entities like sets. So that is how I would respond to the person who attempts to show on the basis on scientism that belief in God is not reasonable.

Question: We touched on this but aren’t both of these forms of naturalism contradictory? If you are totally a naturalist, any form of knowledge you say you compile from the natural world is illusory – you have no guarantee that what happened years ago or today will happen in the next 30 seconds.

Answer: Yeah, I agree with you. As I said, I think epistemological naturalism is self-defeating in the way I explained. But I also think metaphysical naturalism is ultimately self-defeating because I think Rosenberg is right that in a world of only physical entities there would not be what philosophers call intentional states. What does that mean you ask? Well, intentional states are states that have intentionality or the property of being about something or of something. It signifies the object directedness of our thoughts. I can think about my summer vacation. Or I can think of my wife. So my conscious states, my thoughts, have this sort of intentionality to them. They have this object directedness. They are about something. They are thoughts of something. Now, think about this. No physical object has intentionality. A chair isn’t about something. A stone isn’t about something. A glob of tissue like the brain sitting in your skull isn’t about something. Intentionality is a feature of consciousness, of mental states. So in a world in which only physical objects exist, there would not be any intentional states – there wouldn’t be any thoughts about anything. In that respect, I think Rosenberg is right. But then it just seems to follow clearly that metaphysical naturalism is false because I can think about metaphysical naturalism! Right? I have thoughts about metaphysical naturalism – whether it is true or false. So the very fact that I can think about this theory shows that the theory is false! Because, on the theory, there would be no intentional states. So I think you are absolutely right. Both of these ultimately reduce to self refutation and absurdity.

Question: That intentionality is with a “t” as opposed to an “s,” right?[10]

Answer: Yes, that is right - with a “t.”[11]

Followup: I was wondering if metaphysical naturalists have tried to reduce aboutness to a physical state of affairs.

Answer: I think some would say that aboutness can be explained simply in terms of behavior or function. That, to have a thought about something is to behave in a certain way – a kind of behaviorist view. But that is obviously, I think, incorrect. When I think about something it has nothing to do with my behavior; it is the object directness of my thoughts.

Followup: So there is pretty good support that it is irreducible? Intentionality even among many philosophers of the mind is pretty much irreducible?

Answer: Obviously, there are proponents of every view. I mean, look at Rosenberg. He thinks you don’t exist. Everything is controverted. But I would say that the view that intentional states are not something that is characteristic of a physical object is pretty solid and that, therefore, they require some sort of mental states. And the question would be whether or not the naturalist can make room for mental states in his view. Rosenberg thinks not and therefore he says they are illusory.

Followup: I sense supervenience is different than reducibility, right?

Answer: Right.

. . . I didn’t expect to be talking about these things today but it is just as well, they have been on my mind. If I have a mind; I think I do. [laughter]

Question: Would you say methodological naturalism denies agent causation altogether?

Answer: I would prefer to say that metaphysical naturalism would deny agent causation because there isn’t any intentionality if there are just brain states and there are no mental states. You said methodological naturalism – I don’t think that that has to deny these other things. It could admit that there are these non-natural entities and theories and truths about them but I, as a scientist, just can’t consider them. So you have to understand how weak methodological naturalism is. I think a great many Christian scientists would accept it. They would say, and I’ve heard them say, when I go into the laboratory and put on my white coat, I have to only consider what would naturally explain what is going on in this lab experiment. The project of science is just to find natural causes. It doesn’t mean there aren’t any non-natural causes but I, as a scientist, just am not looking for them. So methodological naturalism, I think, is very, very weak and would be completely consistent with saying there are agents who have causal effects upon things but you would not be able to appeal to them in your physical theory. You would just be able to talk about the brain.

Followup: That seems to be a problem because if you just say I can’t really talk about agents – while there might be agents, I can only recognize in my data event causation – isn’t the scientist acting as an agent to bring a set of circumstances about in which an experiment is conducted and therefore really undermining the project all together?

Answer: Well, now, except think about it. The methodological naturalist isn’t offering a theory about what he, himself, is doing. So you might be right that it would imply the reality of agents but he is not denying that and he is not offering a theory about that. So the neurobiologist or the neurosurgeon can offer theories about the brain and why these neurons fire and so forth even if that requires a self-conscious agent to carry out those physical biological experiments. I don’t think that that is self-defeating. That would just be to say that this neuroscientist is adopting a very limited project just like the man with the metal detector is looking for metallic objects and he is not looking for wooden or plastic objects.

To recap, I am not persuaded that the scientist needs to be committed to methodological naturalism. As I say, it could lead to very odd situations where we would be prevented from knowing the truth about the world simply because of our methodology which seems perverse. But, in any case, that is not our project in this class. What we want to do is look at things from a theological standpoint and ask how can we, as Christian theologians, best integrate our theology and the best evidence of contemporary science concerning the origin of life and biological complexity. With that said, what we will do next time is to open the question of the origin of life. How did life come about on this planet and how is this best understood from a Christian point of view? That will be the question that we will begin to explore next time.[12]

[1] 5:13

[2] Phillip E. Johnson is best known as one of the founders of the intelligent design movement and is a staunch opponent of Darwinism.

[3] 10:11

[4] Another example of this can be seen in Q&A #205 “Is Scientism Self-Refuting” on – see – where Dr. Craig addresses the same question/objection.

[5] For a video of this debate, see (accessed July 31, 2013).

[6] 15:16

[7] Dr. Feser uses this analogy as part of his refutation to Alex Rosenberg’s scientism as defended in Rosenberg’s book The Atheist’s Guide to Reality. See Dr. Feser’s blog post at (accessed January 28, 2013)

[8] 20:15

[9] “If I saw indirect explanatory benefit in positing sensibilia, possibilia, spirits, a Creator, I would joyfully accord them scientific status too, on a par with such avowedly scientific posits as quarks and black holes.” W. V. O. Quine, “Naturalism; or, Living within One’s Means,” Dialectica 49 (1995): p. 252.

[10] 25:03

[11] This question is just asking for clarification that the concept being discussed is “intentionality” not “intensionality.”

[12] Total Running Time: 30:50 (Copyright © 2013 William Lane Craig)