bookmark_borderPlantinga Calls This A Good Argument for God’s Existence?

The title of my post might come across as snarky, so I want to begin my making it clear that is not my intent. In fact, I want to go on record as saying I have great respect for Plantinga’s skill as a philosopher. Among other things, I think he succeeded in his attempt to refute Mackie’s version of the argument from evil.
Perhaps because I have to come hold Plantinga’s work to such a high standard, I continue to be surprised whenever I read Plantinga’s version of the so-called argument from beauty. In his famous lecture, “Two Dozen or So Theistic Arguments,” Alvin Plantinga sketches what he calls the “Mozart Argument.”

On a naturalistic anthropology, our alleged grasp and appreciation of (alleged) beauty is to be explained in terms of evolution: somehow arose in the course of evolution, and something about its early manifestations had survival value. But miserable and disgusting cacophony (heavy metal rock?) could as well have been what we took to be beautiful. On the theistic view, God recognizes beauty; indeed, it is deeply involved in his very nature. To grasp the beauty of a Mozart’s D Minor piano concerto is to grasp something that is objectively there; it is to appreciate what is objectively worthy of appreciation.

Plantinga doesn’t say how he rates the strength of the individual arguments; it’s possible that he views this argument as providing just a teeny-tiny bit of evidence that is just barely more probable on theism than on naturalism. Of course, it’s also possible that he views this argument as a “killer refutation” of a naturalism. Or, perhaps more likely, maybe he views it somewhere in between.
Let’s evaluate this argument the same way Plantinga evaluates arguments from evil against theism. How do we do that? By trying to clarify the claim the argument makes about the relationship between the evidence to be explained (in this case, objective beauty) and the rival explanatory hypotheses (e.g., theism and naturalism). Nothing in the passage above suggests that Plantinga claims that objective beauty is logically inconsistent with naturalism. Rather, Plantinga seems to be suggesting that objective beauty is less probable on naturalism than on theism.
I’m going to attempt to “steel man” Plantinga’s argument. The most charitable interpretation of Plantinga is that he’s offering the following argument:
(1) Objective beauty exists.
(2) Naturalism is not intrinsically much more probable than theism. [See Plantinga’s argument L]
(3) The existence of objective beauty is more probable on theism than on naturalism, i.e., Pr(beauty|theism) > Pr(beauty|naturalism).
(4) Therefore, everything else held equal, naturalism is probably false, i.e., Pr(naturalism) < 1/2.
I find this argument unconvincing; indeed, I find it so unconvincing I confess I find it hard to understand why Plantinga would endorse it.
First, I think the truth of (1) is far from certain. It’s far from obvious to me that such a thing as objective beauty exists; I don’t even have the intuition that it exists. And Plantinga offers no reason to think that it does. If it doesn’t exist, then there is nothing to explain and this argument cannot even get off the ground.
Second, I think (2) is false. Purdue University philosopher Paul Draper has convinced me that intrinsic probability is determined by modesty, coherence, and nothing else. Again, the only thing I could find in Plantinga’s lecture is a reference to Swinburne’s work on intrinsic probability. Swinburne argues that simplicity determines intrinsic probability. To be sure, there is a correlation between modesty, coherence, and simplicity. But correlation is as far as it goes. And if Draper is correct that intrinsic probability is determined by modesty and coherence, then naturalism is intrinsically much more probable than theism for the simple fact that naturalism (a/k/a “source physicalism”) is much more modest than theism, just as supernaturalism (a/k/a “source idealism”) is much more modest than theism.
Third, let’s assume, but only for the sake of argument, that (1) is true. There really is such a thing as “objective beauty.” What might be the metaphysical or ontological grounding for it? One option is Platonism, i.e., abstract objects. In other words, facts about objective beauty would be nothing more or less than necessary truths about beauty. And since Draperian naturalism (or “source physicalism”) says nothing about whether abstract objects exist, this metaphysical grounding is available not just to theists, but also to naturalists. And Plantinga offers no reason to reject this naturalistic explanation.
Instead, Plantinga considers an evolutionary explanation. Perhaps, he suggests,

our alleged grasp and appreciation of (alleged) beauty is to be explained in terms of evolution: [it] somehow arose in the course of evolution.

But this isn’t an apples-to-apples comparison. Plantinga isn’t comparing a naturalistic explanation of objective beauty to a theistic explanation of objective beauty. On the naturalistic side of the equation, he’s not considering the explanatory power of naturalism to account for objective beauty; rather, he’s considering the explanatory power of naturalism conjoined with an auxiliary hypothesis (about evolution) to account for our grasp and appreciation of alleged beauty. Similarly, on the theistic side of the equation, he’s not considering the explanatory power of theism to account for objective beauty; rather, he’s considering the explanatory power of theism conjoined with an auxiliary hypothesis (about God’s nature) to account for … what, precisely? Our grasp and appreciation of real, not just merely alleged, beauty? God’s causation of objectively beautiful features of the natural world? Something else? Plantinga never says.
The problem isn’t that he invokes auxiliary hypotheses; the problem is that doing so raises a whole bunch of questions which Plantinga doesn’t even ask, much less answer. For example, what’s the antecedent probability of his proffered evolutionary explanation, conditional upon the truth of naturalism? Likewise, what’s the antecedent probability of his auxiliary hypothesis to theism, that facts about objective beauty are somehow related to God’s nature, conditional upon the truth of theism? (And how does that compare to an alternative auxiliary hypothesis about theism, namely, that facts about objectively beauty are grounded in an autonomous realm of abstract objects?) Since Plantinga doesn’t answer these questions, his defense of his Mozart argument is far from complete.
Fourth, let’s assume, but only for the sake of argument, that premise (3) is true. The fact, if it is (were?) a fact, that objective beauty exists hardly exhausts what we (would?) know about “beauty.” As Draper points out, while the universe is saturated with visual beauty, it is not saturated with auditory, tactile, or other sensory beauty. Given that beauty “exists” at all, facts about the kinds and distribution of beauty favor naturalism over theism. So, once the evidence about beauty is fully stated, it’s far from obvious that it favors theism over naturalism.
In fairness to Plantinga, I want to remind readers that Plantinga was merely sketching his Mozart argument in the context of a speech about two dozen or so arguments; he wasn’t trying to give a sustained or even a precise defense of the argument. Nevertheless, I think the above objections pose significant obstacles to such an argument. Even when the argument is steel manned, as I have tried to do here, I cannot see how the argument can overcome these objections.

bookmark_borderHow Theists Can Avoid God-of-the-Gaps Arguments and Still Argue for God

Background: In the context of a review of Dan Barker’s book, Godless, Randal Rauser had a very brief, even cryptic, exchange in the combox for his about God-of-the-Gaps (GOTG) arguments. (See here and here.) That exchange led to his latest post, which you can read for yourself here. I’ve decided to post my response on my own blog here, with some edits for further clarification.


I haven’t read Barker’s book, so I can only comment on what you have quoted:

“Many of these [theistic] arguments are reduced to a ‘god of the gaps’ strategy. At most, the theists might prove the existence of a current gap in human knowledge, but this does not justify filling the gap with their god. After all, what happens when the gap closes someday? The gaps are actually what drive science–if we had all the answers there would be no more science.” (Godless, 104-5)

Let’s start with the ‘god of the gaps’ (GOTG) strategy. What is a GOTG argument and why are such arguments so bad?
Theistic Argument Schema #1 (Focus on Gap in Scientific Knowledge)
GOTG arguments go like this.
(1) There is some fact, F, which science cannot explain today (in terms of naturalistic, mechanistic, unguided) causes
(2) [probable] Science will never explain be able to explain F. [inductive inference from 1]
(3) The existence of God does explain F.
(4) Therefore, the existence of God is the best explanation for F. [from 2 and 3]
(5) [probable] God exists. [inductive inference from (4)]
The key feature of schema #1 (and other schemas like it) is that “science cannot explain F today” plays a major role in the argument.
The move from (1) and (2) is weak. Science has been extremely successful in explaining a wide variety of phenomena in terms of naturalistic, mechanistic causes. Before we even get into the specifics of F, it’s already extremely likely that F has a naturalistic, scientific explanation. In Bayesian terms, “F has a naturalistic explanation” has a high prior probability. This is why I agree with the Barker quotation.
Theistic Argument Schema #2 (Focus on Content of Propositions)
(1) There is some fact F, we know to be true.
(2) The content of the proposition, “The mental exists and, if anything physical exists, explains why anything physical exists” (hereafter, “source idealism”), provides us with reason to expect F or, if it doesn’t provide a reason to expect F, makes F less surprising than it would be on “source physicalism.”
(3) The content of the proposition, “The physical exists and, if anything mental exists, explains why anything mental exists,” (hereafter, “source physicalism”), provides no reason to expect F (or it provides some reason, but less of a reason than what “source idealism” provides).
(4) Therefore, we’d expect F more on the assumption that source idealism is true than on the assumption source physicalism is true.
(5) [probable] Source physicalism is false.
The key feature of schema #2 (and other schemas like it) is that “science cannot explain F today” plays no role whatsoever in the argument. Although F might, indeed, be a fact that science has no explanation for, the lack of scientific explanation for F does zero work in the argument. (In fact, the lack of a scientific explanation for F isn’t even a premise in the argument!) What does do the work in the argument? The content of the propositions represented by the labels “source idealism” and “source physicalism.”
This is a major advantage of schema #2 over schema #1: because “science cannot explain F today” plays no role whatsoever in the argument, schema #2 makes an objection based on the history of science irrelevant. If I were a theist trying to make an argument for God’s existence based one some fact F–a fact which in principle could have a scientific explanation but currently does not (such as fine-tuning, origin of life, consciousness, free will, etc.)– I would use schema #2, not schema #1.
Example: An Argument from Consciousness Using Schema #2
For example, suppose we decide to adopt schema #2 as a “template” for theistic arguments (specifically, natural theology) and we want to try it out with consciousness. This would yield something like the following.
(1) Consciousness exists.
(2) The content of the proposition, “The mental exists and, if anything physical exists, explains why anything physical exists” (hereafter, “source idealism”), provides us with reason to expect consciousness or, if it doesn’t provide a reason to expect consciousness , makes consciousness less surprising than it would be on “source physicalism.”
(3) The content of the proposition, “The physical exists and, if anything mental exists, explains why anything mental exists” (hereafter, “source physicalism”), provides no reason to expect consciousness.
(4) Therefore, we’d expect consciousness much more on the assumption that source idealism is true than on the assumption source physicalism is true.
(5) [probable] Source physicalism is false.
In this case, source idealism not only ‘predicts’ that something mental exists, but it says that something mental explains the existence of everything physical. In other words, something irreducibly mental plays a ‘deep’ role in a theistic worldview. In contrast, source physicalism is logically compatible with the nonexistence of anything mental. If source physicalism is true, the only want to ‘get’ something mental is to have living organisms with bits of matter arranged in very specific and complex ways (e.g., organisms with brains or something very much like a brain). But source physicalism is logically compatible with all sorts of scenarios where such bits of matter never get into that kind of arrangement. For example, source physicalism is logically compatible with a possible world in which only one universe exists, the universe allows carbon-based life, carbon-based life arises through naturalistic abiogenesis mechanism, and then evolution never progresses past single-celled life. Source physicalism is also logically compatible with a similar possible world, but with no life whatsoever. And so on.
In a source physicalism world, mental phenomena like consciousness do not play the kind of ‘deep’ role that they play in a source idealism world. (That’s the whole point of source physicalism.) And so the existence of mental phenomena like consciousness–even if consciousness turns out to have a naturalistic, scientific explanation–is very surprising on source physicalism but expected on source idealism.
The ‘Catch’
If a theist decides to use schema #2, however, there is a catch: in order to maintain logical consistency, the theist is required to admit that there are good, parallel arguments against source idealism and for source physicalism.
For example, notice the symmetry in the definitions of source idealism and source physicalism: one is based upon the mental and the other based upon the physical. You might say that the argument from consciousness described above is a version of an argument family we can call ‘arguments from mentality.’ Source physicalists have a corresponding argument family of their own, what we can call ‘arguments from physicality.’ Similar to the argument I defend in this post, source physicalists can argue as follows.
(1) Matter exists.
(2) The content of the proposition, “The physical exists and, if anything mental exists, explains why anything mental exists” (hereafter, “source physicalism”), provides us with reason to expect matter or, if it doesn’t provide a reason to expect matter, it makes the existence of matter less surprising than it would be on “source idealism.”
(3) The content of the proposition, “The mental exists and, if anything physical exists, explains why anything physical exists” (hereafter, “source idealism”), provides us with no reason to expect expect matter.
(4) Therefore, we’d expect matter much more on the assumption that source physicalism is true than on the assumption source idealism is true.
(5) [probable] Source idealism is false.

bookmark_borderHere’s One Way to Resist Naturalistic Arguments: Lack Belief that Matter Exists!

A Christian apologist writing under the pseudonym ‘InvestigativeApologetics’ stated the usual objection to atheism, namely, that it’s impossible to prove or give evidence for the non-existence of God.

The fact is that atheists who yell that “there is no evidence for God (or Christianity)” are protesting too much, so to speak, and they are, in fact, projecting the weakness of atheism onto theism. For truth be told, it is atheism, at least when in its wide and positive sense, that is the view for which there is no evidence or argumentation that could establish its position. (LINK)

I responded as follows:

Yawn. InvestigativeApologetics seems completely oblivious about the ways to establish the truth of atheism. 

LINKS: herehere

InvestigativeApologetics then doubled down on his original claim, but with a very novel justification.

Yawn all you like. I am intimately familiar both with those two links and with the various Evidential Arguments that you present at the Secular Outpost. In fact, funny enough, it was your arguments that inspired me to look into this matter and come to the conclusion that I did concerning the un-evidenced nature of atheism (when viewed broadly and positively).

Now, obviously, I cannot show this conclusion in this particular comment (although further comments may follow) and I am simultaneously–at this point in my life–beyond caring whether people are swayed by my points or not (for convincing a flesh-and-blood person is not the same as having a convincing argument). However, let me just make a few quick points:

1) First, I am not saying that we must prove that a god does not exist with certainty in order to be rational to believe that a god(s) does not exist. Rather, I am saying that the atheist cannot even show that it is more probable than not that a god does not exist…at least not without begging the question in a substantial number of ways that the theist or skeptic need not grant.

2) For example, consider all the evidential arguments that you present on the Secular Outpost in light of the Likelihood Principle (that a data/observation counts as evidence for Hypothesis 1 over Hypothesis 2 if the data/observation is more likely or expected on Hypothesis 1 than on Hypothesis 2):

a
The Evidential Argument from Scale (AS) – Given the kind of being described in my first comment, no specific scale of the universe would count as evidence against its existence, and all “scale types” would be equally expected on both naturalism and that form of theism. Thus, no evidential support for naturalism (and I know that you don’t fully or strongly endorse the argument from scale, but I wished to present it anyway). 

b. The Evidential Argument from the History of Science (AHS) – This argument was ripped apart in a past discussion that I remember (with Crude and CL and others, I believe…I’m sure you will disagree, but that is not surprising given that philosophy is a discipline of disagreement), and it has (at my last count) at least 10 flaws, but its worst flaw is that it assumes both that there is such a thing as “matter” and that there is such a thing as a “naturalistic” cause (or explanation), but neither of these need be accepted by the theist or skeptic, either of whom could be an immaterialist (or a-matterist) and/or an occasionalist (where God is the only true cause). So your argument rests on an assumption that need not be conceded, and hence, the argument is flawed from the start. It is also circular given that you need to deal with the objection from the occasionalist, but to do that, you cannot assume a natural cause, which is what the occasionalist denies; you would either have to disprove occasionalism or disprove the existence of any god through other means, but this, in turn, makes your argument redundant. So the argument is either redundant or begs the question. Not a good state for an argument to be in. Furthermore, even if the existence of “naturalistic” explanations was conceded, it would still be the case that if a deist non-interventionist god existed, we would expect all explanations to be naturalistic even on this type of deism, and so again, there is no evidential value in favor of naturalism or deism with this argument as naturalistic explanations would be equally likely on both worldviews.

1. InvestigativeApologetics’ comments about the AHS are confused. Theism,’ as I have defined it, is the ‘core‘ explanatory hypothesis. Sectarian doctrines like occasionalism and non-interventionism are auxiliary hypotheses, viz., theism does not entail occasionalism or non-interventionism but is compatible with both. They are at, at best, uncertain. The probability calculus specifies how we should deal with uncertain auxiliary hypotheses in a way that conforms with the pattern of probability relations specified by Bayes’ Theorem. I explain this here. What IA needs to do is provide an antecedent reason on theism for expecting that either or both of these auxiliary hypotheses are significantly more likely than their denials. Otherwise, the logically correct conclusion is to dismiss these objections as ad hoc, “just so” stories invented solely to avoid the conclusions of the arguments. “Both worldviews” might have roughly equal explanatory power, but naturalism would trump deism by virtue of having a greater intrinsic probability.
2. More important, a careful reading of my arguments will reveal that my arguments need not presuppose that material objects exist.  Supernaturalism (or “source idealism”) can be defined in a way that is neutral between dualism and idealism.  (The hypothesis that the original causes of any material objects that exist are immaterial does not entail that material objects exist.)  Similarly, naturalism or “source physicalism” can be defined in a way that is neutral between dualism and materialism.  Notice too, that even if my particular definition of supernaturalism implies the existence of material objects, that is compatible with “identity idealism”, which is far more plausible than eliminative idealism, just as identity materialism is far more plausible than eliminative materialism.  (Berkeley was an identity idealist, for example.  He believed that physical objects exist, but thought they were collections of ideas.) (I owe this point to Paul Draper.)

c. The Evidential Argument from Biological Evolution (ABE) / The Evidential Argument from Physical Minds (APM) / The Evidential Argument from Evil: The Biological Role of Pain and Pleasure (AE: APP) / The Evidential Argument from Evil: The Flourishing and Languishing of Sentient Beings (AE: AFL) / The Evidential Argument from Evil: The Self-Centeredness and Limited Altruism of Human Beings (AE: AVV) – See Point (a) – Again, none of these arguments hold any evidentiary weight against a non-interventionist god and so do not support naturalism over such a deism given that all these facts would be equally likely on naturalism or deism.

Now, to be precise, my “arguments for naturalism” are really arguments against theism, though in some sense they are of course both.

Now, you could, of course, try to claim that aspects of prior probability or modesty/coherence (from Paul Draper’s ‘Burden of Proof’ Argument, which I know you support) might make atheistic-naturalism more rational or more likely than some type of theism. But again, there are numerous problems with such maneuvers. First, prior probabilities are notoriously difficult to establish objectively, and I, on that basis alone, I would be suspicious of any argument, by an atheist, which just happens to show that atheism (or atheistic-naturalism) has a higher prior probability than theism.

IA knows very well that suspicion is not an argument. And notice that IA gives no reason to doubt that intrinsic probabilities should be determined solely by scope and coherence. Furthermore, he neglects to mention that Draper’s theory of intrinsic probability does result in the conclusion that naturalism and supernaturalism have equal intrinsic probabilities. Once that fact is taken into consideration, it becomes clear that Draper’s theory is not biased against supernaturalism. The fact that theism has a smaller intrinsic probability than supernaturalism follows directly from the definitions of supernaturalism and theism. Theism entails supernaturalism but supernaturalism does not entail theism. So the probability of theism cannot be any greater than the probability of supernaturalism but could be less. This is basic, non-controversial set theory.

Second, in all your arguments (and your priors) you begin with the assumption that materialism—in the sense of metaphysical matter actually existing—is true, but I do not concede this assumption (being an a-matterist and thus lacking a belief in the existence of matter) and so this must be proven before any one of your arguments gets off the ground and before you can even set the prior probabilities that you want. Third, modesty and coherence does not favor naturalism, but rather a type of Berkelian immaterialism, for it is that view that makes the least assumptions about reality (only thinking things exist, which we cannot deny, and is thus the most modest) while remaining coherent (and it is arguable that atheistic-naturalism even is coherent), so Draper does not help you much.

Addressed above.

Fourth, even if we grant the existence of matter, given the fact that a “material god” could exist, and given that a good case could be made that the prior probability of a “material god” existing is either just as good or better than the prior probability of straight atheistic-naturalism (for consciousness, language, life, would have a higher probability of existing given the existence of a material god than given just straight atheistic-naturalism), then, once again, your arguments run into trouble.

What is a “material god”? The word “material” tells us that such a being is composed of matter. The word “god,” I gather, is supposed to tell us that such a being has supernatural powers or abilities. The hypothesis that such a being exists is a very specific version of supernaturalism and so, like theism, has a smaller intrinsic probability than supernaturalism and naturalism. (The more a hypothesis claims, the more ways there are for that hypothesis to be false and so the lower the intrinsic probability.) So-called ‘theistic evidences’ — such as consciousness, language, life, and so forth — determine the explanatory power of the ‘material god’ hypothesis, not its intrinsic probability. Furthermore, notice that IA lists only alleged theistic evidences. It seems rather one-sided to estimate the probability of a material god existing by considering only theistic evidences, while ignoring naturalistic evidences (such as pain and suffering, evolution, nonresistant nonbelief, mind-brain dependence, and so forth). Once the evidence is fully stated, it’s doubtful that IA’s “material God” exists.

Now, I am certain that you might scoff at certain proposals that I have put forward (for example, immaterialism or occasionalism) as being not worthy of consideration. And that’s fine. But my point is this: I do not need to concede to the very assumptions which are latent in so many of the arguments that you put forward, and the moment I do not concede to those assumptions, not only do your arguments lose nearly all their force (if not all), but you actually have the burden to prove the things that you are asserting. And demonstrating such things (such as the actual existence of matter, for example) is a very difficult task to say the least. Furthermore, until and unless you do demonstrate the existence of these things you just essentially assumed, I could readily contend that you hold to them with little more than blind faith. And so these are just some of the brief reasons why, when atheistic arguments are thoroughly deconstructed, and when we realize the various underlying assumptions that they make—assumptions which we need not grant—and when we also understand that the atheist is literally denying the existence of all reasonably possible gods, which could and would include a god such as a non-interventionist one, then we can begin to understand why the atheistic position, when viewed broadly and positively, lacks any evidence for its claim. 

I’m not sure about “scoffing,” but I will say this. If the best response a person has to my arguments is to doubt or deny the existence of matter, then I’m feeling pretty good about the arguments. This must be how Christians feel when atheists use certain far-fetched objections.(“If this is the lengths they have to go to in order to deny the argument, then let them have it.”)