bookmark_borderDoes “Science” Make Theism Likelier than Atheism?

Victor Reppert recently linked to an article on the blog Saints and Sceptics (S&S), Why Science Makes Theism Likelier than Atheism.” In this blog post, I’m going to critically assess that article.
1. What is the Evidence to be Explained?
S&S begin their article as follows:

Should we view the order of the universe, and our ability to comprehend that order, as evidence of God?

This question suggests two related but independent items of evidence to be explained:

E1. The universe is orderly.
E2. The universe contains intelligent beings able to comprehend that order.

Regarding E1, S&S don’t clarify or explain what they mean by phrases like “the order of the universe” or, elsewhere, “the high degree of order” of the universe. In order to be charitable, I’m going to “steel man” their argument by assuming they are appealing to something similar to what Christian philosopher Richard Swinburne calls the “arguments from spatial and temporal order” in his book, The Existence of God.  The argument from temporal order appeals to the fact that “there are regular successions of events, codified in laws of nature.”[1] The phrase “regular succession of events” is key; this is why, I suppose, Swinburne calls it the argument from temporal order. In contrast, the argument from spatial order appeals to the fact that, given our universe conforms to simple, formulable, scientific natural laws, “our bodies are suitable vehicles to provide us with an enormous amount of knowledge of the world and to execute an enormous variety of purposes in it.”[2] This “steel man” interpretation seems highly charitable, since E1 seems to correspond with Swinburne’s argument from temporal order, whereas E2 is very similar to Swinburne’s argument from spatial order.[3]
Accordingly, we may clarify E1 as follows.

E1′. The universe conforms to simple, formulable, scientific laws.

With the evidence to be explained sufficiently clarified, let’s unpack their argument.
2. What, Precisely, Is the Argument?
Before I can turn to the logical structure of S&S’s argument, let’s first review some notations which will make it easier to summarize the argument in a concise form.

Pr(x): the epistemic probability of any proposition x
Pr(x | y): the epistemic probability of any proposition x conditional upon y
“>!”: “is much more probable than”
“>!!”: “is much, much more probable than”
T: theism
A: atheism. A is logically equivalent to ~T.

The first premise of the argument is a simple statement of E1′:

(1) E1′ is known to be true, i.e., Pr(E1′) is close to 1.

Let’s now return to S&S:

Let’s start with atheism. From an atheistic perspective, there doesn’t seem to be any explanation for the order in the universe; it would just be a brute fact or a ‘happy accident’ as Polkinghorne puts it.
But that doesn’t seem good enough. In the absence of an explanation, we would have no reason to expect the high degree of order that we find. But does theism fare any better? To many it seems very likely that if the universe is the product of an intelligent mind, it would exhibit order.  …

So the second premise of the argument seems to be:

(2) An orderly universe is antecedently much more probable on the assumption that theism is true than on the assumption that atheism is true, i.e., Pr(E1′ | T) > Pr(E1′ | A).

The third premise is a simple statement of the evidence E2.

(3) E2 is known to be true, i.e., Pr(E2) is close to 1.

Returning to S&S:

But does theism make an intelligible universe – especially one which is governed by comprehensible laws and which can described by mathematics – any more likely? …
If our minds are the result of design we could rely on them to discover the truth. Rational rulers used laws to govern – and God was the ruler of the universe. And it would not be surprising to discover that mathematics could describe the universe if the divine mind and human minds were analogous in at least some respects. Finally if the universe is created by a good God, he would not systematically deceive us. In light of these considerations, Kepler and his fellow scientists were surely right to think that there is much more reason to expect an intelligible universe if there is a God than if there is not.

So the next premise seems to be:

(4) An intelligible universe is antecedently much more probable on the assumption that theism is true and an orderly exists than on the assumption that atheism is true and an orderly universe exists, i.e., Pr(E2 | T & E1′) > Pr(E2 | A & E1′).

Finally, S&S concludes:

So it is obvious that any complex, valuable, beautiful and intelligible state of affairs – including our universe – is much, much more likely given theism than chance.

And so the conclusion of their argument is:

(5) Therefore, theism is a much, much more likely explanation for the order and intelligibility of the universe than chance, i.e., Pr(T | E1′ & E2)  >!! Pr(chance | E1′ & E2).

We are now in a position to concisely state the argument in its logical form.

(1) Pr(E1′) is close to 1.
(2) Pr(E1′ | T) > Pr(E1′ | A).
(3) Pr(E2) is close to 1.
(4) Pr(E2 | T & E1′) > Pr(E2 | A & E1′).
(C) Therefore, Pr(T | E1′ & E2)  >!! Pr(chance | E1′ & E2).

Let us now turn to evaluating the strength of this argument. While I have many objections to this argument, let me present just four.
3. First Objection: The Argument Ignores Intrinsic Probabilities
This argument is a deductive argument about inductive probabilities. As stated, however, the argument is incomplete. It does not contain any premises regarding the prior probabilities of theism and atheism. But Bayes’ Theorem shows that posterior or final probabilities are a function of two things: prior probability and explanatory power. S&S write much about the latter, whereas they are completely silent about the former. This invalidates their argument. It’s possible that (1) – (4) could all be true and yet the conclusion, (C), still might not follow if the prior probability is extremely low.
In order to repair the argument, S&S would need to add a premise to their argument which explicitly addresses the prior probabilities of theism and atheism. Now, applying the concept of a “prior probability” to a metaphysical hypothesis like theism is tricky. It isn’t clear from S&S’s article which propositions they would include in their background information for the purpose of assessing a prior probability, and I do not know of a non-controversial way to choose such propositions. Fortunately we don’t have to solve that problem; another option is to replace “prior probability” with “intrinsic probability.” As the name implies, an intrinsic probability is the probability of a hypothesis based solely on intrinsic factors relating to its content (i.e., what it says); it has nothing to do with extrinsic factors, such as the relationship between a hypothesis and the evidence to be explained.
In an attempt to “steel man” S&S’s argument, I propose that we adopt Paul Draper’s theory of intrinsic probability, which says that the intrinsic probability of a hypothesis is determined by its scope, its modesty, and nothing else. Draper explains modesty and scope as follows.

a. Modesty: The modesty of a hypothesis is inversely proportional to its “content”—to how much it says. Hypotheses that say less—for example, because they make fewer claims or less specific claims or claims that are narrower in scope—are, other things being equal, more likely to be true than hypotheses that say more.
b. Coherence: The coherence of a hypothesis depends on how well its components fit together.
c. If we abstract from all factors extrinsic to a hypothesis, then the only thing that could affect the epistemic probability of that hypothesis is how much it says and how well what it says fits together. No other factors affecting probability could be intrinsic to the hypothesis.

Using these criteria, we’re now in a position to compare the intrinsic probabilities of theism and atheism. Before we do that, however, we need to start with the intrinsic probabilities of naturalism and supernaturalism. Here’s Draper:

4. The intrinsic probabilities of naturalism and supernaturalism
a. Naturalism is the statement that the physical world existed prior to any mental world and caused any mental world to come into existence.
b. Supernaturalism is the statement that the mental world existed prior to any physical world and caused any physical world to come into existence.
c. Otherism is the statement that both naturalism and supernaturalism are false.
d. Naturalism and supernaturalism are equally probable intrinsically because they are equally modest and coherent. Since the intrinsic epistemic probability of otherism is greater than zero, naturalism and supernaturalism are each less probable intrinsically than their denials. (So both naturalists and supernaturalists bear a burden of proof and that burden is equal.)
5. The intrinsic probabilities of theism and atheism
a. Theism is a very specific version of supernaturalism and so is many times (i.e. at least 10 times) less probable intrinsically than supernaturalism.
b. Naturalism is a specific version of atheism and so is many times less probable than atheism.
c. Thus, since naturalism and supernaturalism are equally probable intrinsically, it follows that atheism is many times more probable intrinsically than theism, which entails that atheism has a high intrinsic probability (certainly higher than .9) while theism has a very low intrinsic probability (certainly lower than .1)….

Let me introduce a bit more notation:

Pr(|x|): the intrinsic probability of any proposition x

Using that notation, we are now in a position to add the missing premise to S&S’s argument:

(5) Atheism is many times more probable intrinsically than theism, i.e., Pr(|A|) > .9 >!! Pr(|T|) < .1.

Unfortunately for S&S, however, it is far from obvious that the evidence to be explained, E1′ and E2, outweigh the very low intrinsic probability of theism. Accordingly, it’s far from obvious that the conclusion, (C), follows from premises (1)-(5).
4. Second Objection: Pr(E1′ | A) May Be Inscrutable
My second objection to S&S’s argument is that Pr(E1′ | A) may be inscrutable. If it’s inscrutable, then they can’t compare Pr(E1′ | T) to Pr(E1′ | A). Accordingly, the truth of (2) would be unknown. While I’m open to the possibility that (2) is true, I cannot figure out a way to defend it.
Why think Pr(E1′ | A) is inscrutable? In the context of E1′, A is a catch-all hypothesis. A is logically equivalent to A conjoined with all possible explanations for temporal order in the universe apart from theism.[4] For example:

A1: A is true, and the explanation for temporal order in the universe is naturalistic explanation #1.
A2: A is true, and the explanation for temporal order in the universe is naturalistic explanation #2.

An: A is true, and the explanation for temporal order in the universe is naturalistic explanation #n.

That’s a lot of potential explanations. Accordingly, this constitutes a prima facie reason to be skeptical of the claim that Pr(E1′ | A) can be known well enough to support a comparative claim such as (2). The only way to reject this prima facie reason would be to identify some intrinsic feature of A which either ruled out a naturalistic explanation for E1′ or which made such an explanation antecedently less likely than it would be on T. Is there such a reason?
Let’s reconsider part of what S&S write in support of (2):

From an atheistic perspective, there doesn’t seem to be any explanation for the order in the universe; it would just be a brute fact or a ‘happy accident’ as Polkinghorne puts it.

By “brute fact,” I assume that S&S mean “a fact which has no explanation.” By “happy accident,” I assume that Polkinghorne means due to chance. But “brute fact” and “happy accident” hardly constitute an exhaustive set of the possibilities. Let me add just one more to the list: factual necessity. Metaphysical naturalism (as defined in the Draper quote, above) is antecedently very probable on the assumption that atheism is true. If metaphysical naturalism is true, then it seems highly plausible that physical reality — whether that consists of just our universe or a multiverse — is factually necessary.  If physical reality is factually necessary, it seems highly plausible that temporal order could also be factually necessary. But if temporal order is factually necessary, then it is just factually necessary and there is nothing for atheism to explain.
Admittedly, the hypothesis, “our universe and its laws are factually necessary,” is highly speculative and not known to be true. But, to paraphrase a point once made by CalTech physicist Sean Carroll, theists like S&S are the ones proposing bizarre thought experiments involving the fundamental laws of nature. So we have to consider such speculative possibilities due to the very nature of the topic and the argument. In any case, this much is clear: S&S give no evidence of having even considered, much less addressed, such a possibility.
5. Third Objection: The Conclusion Confuses Atheism with Chance
My third objection is closely related to my point about factual necessity.

So it is obvious that any complex, valuable, beautiful and intelligible state of affairs – including our universe – is much, much more likely given theism than chance.

The conclusion of the argument does not follow from the premises because the conclusion compares theism to chance, not theism to atheism. But, as we’ve just seen, atheism functions as a catch-all hypothesis. Atheism is compatible with the proposition, “The universe and its temporal order are factually necessary.” N.B. That proposition denies that the order of the universe is due to chance. And S&S provide no reason to think that chance is antecedently much more probable on atheism than factual necessity.
6. Fourth Objection: The Argument Commits the Fallacy of Understated Evidence
As is the case with E1′, I’m open to the possibility that E2, either by itself or when conjoined with E1′, is evidence favoring theism over atheism.[5] In other words, I’m open to the idea that (4) is true. I don’t think S&S have successfully shown this, however. Rather than pursue that objection here, however, I’ll leave that as an exercise for interested readers. Instead, I want to pursue a different objection: even if (4) were true, it would commit the fallacy of understated evidence.
Let’s suppose, for the sake of argument, that the intelligibility of the universe really is evidence favoring theism over atheism. Given that the universe is intelligible, the fact that so much of it is intelligible without appealing to supernatural agency is much more probable on naturalism than on theism. (I’ve defended this argument at length elsewhere, so I will refer interested readers to that defense.) Since naturalism entails atheism, it follows that this evidence favoring atheism over theism.
The upshot is this: even if the intelligibility of the universe is evidence favoring theism, there is other, more specific evidence relating to its intelligibility which favors naturalism (and hence atheism) over theism. It’s far from obvious that the former outweighs the latter.
7. Conclusion
As we’ve seen, there are four good objections to S&S’s claim that science makes theism more likely than atheism. I conclude, then, that S&S’s argument is not successful.
[1] Richard Swinburne, The Existence of God (second ed., New York: Oxford University Press, 2004), p. 153.
[2] Swinburne 2004, p. 154.
[3] The main or only difference between Swinburne’s argument from spatial order and S&S’s E2 is that the former also appeals to our ability “to execute an enormous variety of purposes” in the world, whereas the latter does not.
[4] Herman Phillipse, God in the Age of Science? A Critique of Religious Reason (New York: Oxford University Press, 2012), 258.
[5] For what it’s worth, I think E2 is much more promising than E1′ as a potential source of theistic evidence.

bookmark_borderDoes Atheism Undercut the Case for Equal Human Rights?

Philosopher Victor Reppert thinks so.  I’m not certain, but I think his argument for this claim is supposed to be found in an earlier post of his. At the same time, Reppert, like the overwhelming majority of theists who write about such topics, completely glosses over what atheist intellectuals who specialize in the topic have written. (The writings of Erik Wielenberg would be a great place to start.)
I’d have more respect for Reppert’s argument if he at least gave the appearance of interacting with his dialectical opponents. But, at least in this case, he didn’t do that. What he’s done is no more respectable than, say, an atheist giving an argument from evil and completely ignoring all defenses and theodicies.

bookmark_borderDissatisfaction with Many Arguments for and Against Dualism

Victor Reppert recently posted on his blog the following quotation of Susan Blackmore:

How can objective things like brain cells produce subjective experiences like the feeling that ‘I’ am striding through the grass? This gap is what David Chalmers calls ‘the hard problem.’ …It is a modern version of the ancient mind/body problem – but it seems to get worse, not better, the more we learn about the brain… The objective world out there, and the subjective experiences in here, seem to be totally different kinds of things. Asking how one produces the other seems to be nonsense. The intractability of this problem suggests to me that we are making a fundamental mistake in the way we think about consciousness – perhaps right at the very beginning.
Susan Blackmore, ‘What is consciousness?’, Big Questions in Science, in Harriet Swain (ed.), Big Questions in Science, (Jonathan Cape, 2002), p. 29-40.

This quotation reminds me of why I am dissatisfied with so many arguments for and against dualism. I am not an authority on the mind/body problem so take what I am about to write with a grain of salt, but in my experience most of the arguments:
a. Amount to a statement of incredulity; or
b. Beg the question.
Now, with all due respect to Susan Blackmore (whose work I have not read), the passage just quoted seems to amount to nothing more than a statement of incredulity, as opposed to an actual argument. If physicalism is true, then the mind just is the brain and, it would seem, there is no subjective experience ‘in here.’ It’s not clear to me how that statement of credulity is supposed to be any more compelling than the following:

The problem of mind/brain interaction seems to get worse, not better, the more we learn about the brain… Nothing mental happens without something physical happening. The idea of mental ‘substance’ existing wholly apart from arrangements of physical matter seems to be nonsense. Even if there were a mental ‘substance’ existing ‘out there’, how, precisely, does it interact with arrangements of physical matter?

Why is Blackmore’s passage supposed to be any more compelling than what I just wrote? What have I missed?
In spite of everything I’ve written above, I still think there is a good evidential argument against naturalism based on consciousness. At the same time, I also think there is a good evidential argument against theism based on mind-brain dependence. This suggests to me that the issue is far more complex than simple quotations of supposed ‘hostile’ authorities would seem to suggest.

bookmark_borderWhy Skeptics Do Not Need the Hallucination Theory to Reject the Resurrection

According to Victor Reppert, skeptics need the hallucination theory in order to reject the resurrection. Why? Read his blog post to find out.
I see his point, i.e., I understand where he is coming from when he says that he thinks (non-extreme) skeptics need the hallucination theory. But I disagree with him for at least two reasons.
First, Reppert assumes that the Resurrection hypothesis explains the data, but that’s merely an assumption on his part. He gives no good reasons to believe that assumption is true and there are good reasons to doubt it. The Resurrection hypothesis does not entail an empty tomb, Jesus’ alleged postmortem appearances, or the origin of the Christian faith. He is implicitly combining the Resurrection hypothesis with several extra, add-on, ‘auxiliary’ hypotheses. But then it follows that he is not making an apples-to-apples comparison when he compares the Resurrection hypothesis to its competitors.
Second, as it stands, in his post he fails to consider the full set of mutually exclusive and jointly exhaustive alternative explanations.
This is the case even if we set aside positions based upon ‘extreme skepticism’, such as Robert Price’s suggestion that 1 Corinthians 15 is a post-Pauline interpolation or the mythicist hypothesis (i.e., “Jesus never existed”). Reppert covers all of the traditional bases, such as the theft hypothesis (“the body was stolen”), the survival hypothesis (aka the “swoon theory, i.e., “Jesus survived his crucifixion”), and the wrong tomb hypothesis.
What is left? Here are two alternative explanations.
1. In my book, The Empty Tomb, I defend a hypothesis I call the “relocation hypothesis.” As explained here, the relocation hypothesis is the view that Jesus’ body was stored (but not buried) in Joseph’s tomb Friday before sunset, and moved on Saturday night to a second tomb in the graveyard of the condemned, where Jesus was buried dishonorably.
From a logical perspective, what is significant about this hypothesis is that it entails an empty tomb. In other words, if the relocation hypothesis is true, there is a 100% probability that Jesus’ female followers discovered his (first) tomb empty on Sunday morning. In contrast, the resurrection hypothesis does not entail an empty tomb. (See the paper I just linked for a defense of my last sentence.)
I do not claim that the relocation hypothesis, all by itself, explains Jesus’ alleged post-mortem appearances. The relocation hypothesis would have to be combined with an auxiliary hypothesis to explain the alleged postmortem appearances, just like the Resurrection hypothesis has to be combined with an auxiliary hypothesis. The combination hypothesis of relocation + hallucination is certainly an option, but it’s hardly the only option. One could also combine with the relocation hypothesis with a hoax hypothesis, according to which the hoaxer was neither Jesus nor his early followers.
2. A second alternative explanation is the twin hypothesis, according to which Jesus had an unknown identical twin brother who faked the Resurrection by walking around pretending to be Jesus, after the real Jesus had died. This possibility was identified by Christian historian Paul Maier — note I said “identified” not “defended” — and then defended by Robert Greg Cavin in his Ph.D. dissertation. Unlike the Resurrection hypothesis, the Twin hypothesis entails all of the data to be explained. It has an overall higher balance of prior probability and explanatory power. According to Bayes Theorem, that’s all one needs to show that the Resurrection is not the best explanation.
Christians will often object to both hypotheses by pointing out that there is no direct textual evidence for either scenario, i.e., there is no passage in the NT or in extrabiblical sources which say either of these things happened. That’s true. They don’t. And it is also true that a moment’s reflection will reveal that, if we approach the topic not as a believer in the Bible but the same way we would approach any historical question, we often believe historical claims on the basis of other kinds of evidence besides direct textual evidence. It’s a fallacy to dismiss a historical claim merely on the basis of the lack of direct textual evidence.
I don’t claim that either explanation is true. But I do claim it is far from obvious why the Resurrection hypothesis is a better explanation than either the relocation or twin hypotheses.

bookmark_borderChristian Apologists Ignore the Best Objections to the Moral Argument

(Redated post originally published on 2 August 2014)
To be precise, there are many kinds of moral arguments for theism. The question in the title is really talking about what we might call “ontological” or “metaphysical” moral arguments, the kind which claim that we need God in order to have an “ontological foundation” for objective or absolute morality.
People who defend a version of this kind of argument include a veritable “Who’s Who?” of contemporary Christian apologists: C.S. Lewis (see here and here), Alvin Plantinga (see here and here), William Lane Craig, Paul Copan, J.P. Moreland, Randal Rauser, David Baggett, Jerry Walls, Norman Geisler, Frank Turek, Roger Olson, Michael Horner, and so forth.
While there have been many critics who seem to be clueless about how to refute such arguments (see here and here for just two of probably 100+ available examples), there are many other philosophers who understand the arguments perfectly well and–gasp!–actually offer relevant objections. (What a concept!) In my opinion, the two best critics of ontological moral arguments are Erik Wielenberg (see here and here) and Wes Morriston (see here and here). Why, then, do apologists who’ve written on the topic in the last decade continue to ignore Wielenberg and Morriston?
I’m starting to think Ex-Apologist has a great explanation, albeit one he didn’t invent specifically for this topic. In fact, I think he has a great name for this great explanation. In a post entitled, “Proposal for a New Entry in the Philosophical Lexicon,” he calls this behavior “craiging.” Here is how he defines it.

craig, v. (a) to engage in dialectically illegitimate argumentative maneuvering, such as (e.g.) construing an interlocutor as offering a rebutting defeater for P when it’s more charitable to construe them as offering an undercutting defeater for P[1]; (b) to maintain a somewhat positive image of one’s positions in part by choosing not to address, mention, or cite the strongest criticisms of them; (c) to take up, critique, and/or ridicule an uncharitable construal of the theses and arguments of one’s interlocutor.

[1] Relatedly: to infer or otherwise assume that because a reply fails to rebut P, it also fails to undercut P.

It is (b) which I think applies to contemporary defenders of ontological moral arguments for theism: they simply act as if these critiques don’t exist.

bookmark_borderWeighing Theistic Evidence Against Naturalistic Evidence

In the next-to-last paragraph of his book, C.S. Lewis’ Dangerous Idea: In Defense of the Argument from Reason, Victor Reppert makes a very interesting statement:

However, I contend that the arguments from reason do provide some substantial reasons for preferring theism to naturalism. The “problem of reason” is a huge problem for reason, as serious or, I would say, more serious, than the problem of evil is for theists. (emphasis mine)

I think this is a very interesting statement for two reasons. First, Reppert acknowledges that the so-called “problem of evil” — which is probably misnamed (see here) — is an evidential problem for theism. All by itself, that is a significant concession that is all too rare among theistic philosophers. But second (and more important), Reppert claims that naturalism’s ‘problem of reason’ is as big of a problem, if not a bigger problem, for naturalism as the ‘problem of evil’ is for theism. I want to focus on this second feature of interest about Reppert’s statement.
I recently asked, “Why Do So Many People Have a “Winner Takes All” Approach to Evidence about Gods?” Suppose you agree with my conclusion that there can be evidence for false propositions, so there can be evidence for atheism if God exists, and so there can be evidence for theism if God does not exist.
As soon as you admit that possibility, you have to be prepared to confront another possibility. How do you weigh competing items of evidence, especially when we don’t have numerical probability values (or likelihoods or Bayes’ factors) to work with? Here are two versions of this problem.
(1) Weighing Two Individual Items of Evidence
Suppose you have two items of evidence, E1 and E2, and two rival hypotheses, H1 and H2. E1 is evidence favoring H1 over H2, i.e., Pr(E1 | H1)  > Pr(E1 | H2). Let B1 the “Bayes’ factor” for E1 , i.e., the ratio of Pr(E1 | H1)  to Pr(E1 | H2). E2 is evidence favoring H2 over H1, i.e. Pr(E2 | H2) > Pr(E2 | H1). Let B2 be the Bayes’ factor for E2, i.e., the ratio of Pr(E2 | H1) to Pr(E2 | H2). If E1 is stronger evidence for H1 than E2 is evidence for H2, then B1 > 1/B2. Likewise, if E2 is stronger evidence for H2 than E1 is evidence for H1, then 1/B2 > B1. But how do you show that?
In some cases, it may be possible to show this is true by definition. For example, in my F-inductive argument from consciousness, I argue that Pr(consciousness | theism) =1 because theism entails the existence of consciousness. Now compare that result to a very weak argument against theism, the argument from scale. I have argued before that, as an argument against mere theism, the evidence of scale provides very weak evidence favoring naturalism over theism. So it seems obvious that if Pr(consciousness | theism) = 1, then consciousness is much stronger evidence for theism than scale is against it.
Or consider Paul Draper’s evidential argument from biological evolution. The key insight to understanding that argument is this. It is really an argument against special creationism, combined with a rigorous argument that special creationism is a viable auxiliary hypothesis to theism. In other words, theism provides a significant antecedent reason to expect that special creationism is true conditional upon the assumption that theism is true, where “antecedent” emphasizes the idea that we are abstracting away all of our evidence from biology. Draper’s evidential argument from biological evolution argues that Pr(special creationism | naturalism) = 0, whereas Pr(special creationism | theism) >= 1/2. Now suppose you have some extremely weak argument for theism, such as the argument from beauty. I don’t think beauty provides any evidence for theism, but for the sake of argument let’s pretend that it does. In that case, it would be obvious that the falsity of creationism is much stronger evidence against theism than beauty is evidence for it.
Not all comparisons of evidence will involve cases where at least one hypothesis entails neither the evidence to be explained nor the denial of the evidence to be explained. In those cases, it seems to me it will be more difficult, possibly impossible, to justify an objective comparison of evidential strength. (Whether it is impossible or merely difficult will have to be determined on a case-by-case basis.)
(2) Weighing Cumulative Cases Against One Another
Suppose now you have two “real” cumulative cases done the right way. In favor of H1, you have items of evidence E1 through E5. In favor of H2, you have items of evidence E6-E10. For example, let H1 be theism and H2 be naturalism. Then let our items of evidence be:
E1: the contingency of the universe
E2: the beginning of the universe
E3: the life-permitting conditions of the universe
E4: consciousness
E5: intentionality
E6: the hostility of the universe to life
E7: biological role of pain and pleasure
E8: falsity of special creationism
E9: mind-brain dependence
E10: psychopathy
You believe that E1-E5 are individually and collectively evidence favoring theism over naturalism. Likewise, you believe that E6-E10 are individually and collectively evidence favoring naturalism over theism.
As before, we’ll use “B” to represent the Bayes’ factor. Let B1-5 represent the ratio of Pr(E1 & E2 & E3 & E4 & E5 |T) to Pr(E1 & E2 & E3 & E4 & E5 |N). Let B6-10 represent the ratio of Pr(E6 & E7 & E8 & E9 & E10 | T) to Pr(E6 & E7 & E8 & E9 & E10 | N).
How in the world are you supposed to show that B1-5 > 1/B6-10?
(3) Is Naturalism’s ‘Problem of Reason’ as Big or Bigger than Theism’s ‘Problem of Evil’?
Let us now return to Reppert’s statement I quoted at the beginning of this post:

However, I contend that the arguments from reason do provide some substantial reasons for preferring theism to naturalism. The “problem of reason” is a huge problem for reason, as serious or, I would say, more serious, than the problem of evil is for theists. (emphasis mine)

Reppert does not attempt to defend this claim in his book, but in fairness we should note the argument from reason is a neglected topic in the philosophy of religion. It seems reasonable to devote an entire book just to (re-?)introducing the argument and defending it. But it would be a major accomplishment in the philosophy of religion, I think, if Reppert were able to successfully defend this claim. Perhaps he can devote his considerable philosophical talents to this task in a future book.

bookmark_borderWhen are Theistic Arguments “God-of-the-Gaps” Arguments?

In a recent post, Victor Reppert asks:

Is there any theistic argument [from/in natural theology] that can’t be accused of being a god-of-the-gaps argument? Is this an all-purpose reply to all natural theology?

My answers are “yes” to the first question and “no” to the second question.
I think it would helpful if everyone would agree upon or stipulate what it means for an argument to be a “God-of-the-gaps” argument.
Here’s my proposal: “God-of-the-gaps” arguments have the following logical form.

(1) There is some puzzling phenomenon P which science cannot at present explain.
(2) Theism does explain P.
(3) Therefore, P is more likely on the assumption that God exists than on the assumption God does not exist.

The key feature of this argument–and what makes it a “God-of-the-gaps” argument–is premise (1). The focus is on science’s present inability to explain P.
For example, here’s a God-of-the-gaps argument from consciousness.

(1) Science cannot explain consciousness.
(2) Theism does explain consciousness.
(3) Therefore, consciousness is more likely on the assumption that God exists than on the assumption God does not exist.

But not all arguments in/from natural theology need have this logical structure. For example, they could be presented as what I have called “F-inductive arguments.” If we let B be our background information, E be the evidence to be explained, and H1 and H2 be rival explanatory hypotheses, then F-inductive arguments have the following structure.

1. E is known to be true, i.e., Pr(E) is close to 1.
2. H1 is not intrinsically much more probable than H2, i.e., Pr(|H1|) is not much greater than Pr(|H2|).
3. Pr(E | H2 & B) > Pr(E | H1 & B).
4. Other evidence held equal, H1 is probably false, i.e., Pr(H1 | B & E) < 0.5.

The key feature of this argument is premise 2, which does not make reference to science’s inability to explain P.
To make this more concrete, here’s a non-God-of-the-gaps, F-inductive version of the argument from consciousness. E is the existence of human consciousness; T is theism; and N is naturalism.

1. E is known to be true, i.e., Pr(E) is close to 1.
2. N is not intrinsically much more probable than T, i.e., Pr(|N|) is not much greater than Pr(|T|).
3. Pr(E | T & B) =1 > Pr(E | N & B).
4. Other evidence held equal, N is probably false, i.e., Pr(N | B & E) < 1/2.

Whatever problems may exist with that argument, being a God-of-the-gaps argument clearly isn’t one of them.

bookmark_borderVictor Reppert Calls the Universe Atheists Believe in “Irrational”

In a post titled, “Do you believe in magic?”, Christian philosopher Victor Reppert writes:

I don’t believe that reason could arise from nonreason, therefore I think that reason is at the foundation of the universe. According to the naturalistic view, the normative arises from the nonnormative, the logical arises from the nonlogical, the universe exists without an explanation for its existence even though it looks contingent as all heck, the universe was finely tuned for intelligent life, purposes arise where none existed before, consciousness comes from a lack of consciousness. The very foundations of science don’t even seem possible in the irrational universe that atheists believe in. Even the very fact that our thoughts are about something else is sit omething that can’t be captured by basic physics. It has always seemed to me that the atheists, not the theists, are the ones who believe in magic.

My first reaction upon reading this is that Reppert has demonstrated how to make the case for theism appear much stronger than it actually is by committing the fallacy of understated evidence. My second reaction is that my concept of metaphysical naturalism is very different than what Victor describes. As I define metaphysical naturalism:

If you continue reading past the end of Reppert’s post and into his combox, you’ll find commenters suggesting that “atheism is a form of mental illness” and atheism does not even deserve a seat at the kids’ table. As of the time of the writing of this post, Reppert had not yet responded to any of the commenters stating whether he agrees or disagrees. I hope he disagrees and states as much as in his combox.
Related Post:
Let’s Attack a Straw Man, C.S. Lewis Style!

bookmark_borderTheistic and Atheistic Conversation Killers

Both theists and atheists can make statements which are “conversation killers.” Here are two recent examples from the Blogosphere.

On the atheistic side, James Lindsay recently wrote this.

On that basis, and others like it, it is very difficult to see the matter of theism as something to treat seriously as a philosophical object. We shouldn’t. It is a theological object, and theology is only “pseudo-philosophical,” as Carrier puts it, and pseudo-academic, as I outlined above. No one is required to take such a thing seriously or engage its “best” arguments, as if it has any, as if the real contenders haven’t already been dealt with thoroughly and repeatedly, and as if any argument stands up to the simple and straightforward question that’s been waiting for them all along: “Where’s the evidence?”

But because the idea that we should engage any position’s best case is generally true in philosophy proper, and all academic debate, it is an easy value to turn into a false virtue. The principle simply doesn’t apply here because theology is pseudo-academic, though. Misapplying it as a false virtue, a moral value defining a particular kind of thinker, I think, is exactly what apologists for the philosophy of religion are doing, and I think it constitutes a confusing and unproductive avenue in the conversation that should not continue.

Victor Reppert characterizes Lindsay’s position as, “I’m right; you’re an idiot; so let’s shut the discussion down” (see here). Elsewhere, Reppert asks, “What can you say to someone who wants to shut discussion down?” In response, Lindsay clarifies that this is a close but not perfectly summary of his position:

You are very nearly correct, Victor. It’s not, though, that I want to shut this discussion down (how Orwellian). I just want it to draw to its natural conclusion, if a decade (or century) or more late in getting there.

So Lindsay’s position might be better summarized as: “Theism is obviously stupid (false), so let’s stop having serious conversations about it.”

On the other side of philosophical “aisle,” a reader of Victor Reppert’s blog named Ilion wrote something very similar from the theistic side.

“What fellowship has darkness with light?”

*All* God-deniers are intellectually dishonest with respect to their God-denial. Thus, it is as logically impossible to have a “dialogue” with atheists about God, or “religion”, as it is to have one with you over any of the things you choose to be intellectually dishonest about, such as socialized medicine … for you *will not* acknowledge any of the unwlecome (to statists/leftists such as yourself) truths about it.

I have no idea why Ilion brings up socialized medicine in reference to me (or why he calls me a “statist” or “leftist”), since I’ve never written publicly about any of those things. In any case, the conversation killer is obvious. All atheists are “intellectually dishonest” with respect to their God-denial.
In case there was any doubt about whether Ilion intended to make such a sweeping generalization, he removed that doubt in a follow-up reply.

JJL: “So if Linday’s position can be summarized as “I’m right, you’re an idiot,” yours would be, “I’m right, you’re a liar.” Correct?
It has nothing to do with me, nor with whether I am right. It has to do with the fact that you (plural, collective, inclusive) are intellectually dishonest, which is worse than mere lying.

My position is: “You’re intellectually dishonest. Correct that, and then we’ll see whether you have anything worthwhile to say.”

JJL: “If that is truly your position, then I can’t think of why any atheist would want to dialogue with you.

I’m crushed: people who are worse than liars may not want to “dialogue” with me … because I insist upon dropping the intellectual dishonesty first.

bookmark_borderMelnyk, Goetz, and Taliafero on the AFR

Lately I have been doing a book revision and in the process reflecting on the “Great Debate” between Andrew Melnyk and the Christian philosophers Stewart Goetz and Charles Taliafero. Melnyk defends the thesis of the physical realization of the mental (PRM) and Goetz and Taliafero offer criticisms. Here are my thoughts so far. Comments would be welcome. Sorry for the length and apologies also that I am too lazy to put in references in this draft. The MTB thesis is the claim, broader than Melnyk’s specific one, that minds are in some sense reducible to, caused by, identical with supervenient upon, realized by…etc. the brain.
It appears that if PRM is true, it cannot be rationally believed!
“What this [PRM] seems to imply is that everything that occurs in our mental lives, including our beliefs, is ultimately explicable in terms of physical causation alone without any explanation of that which is irreducibly mental by something else which is irreducibly mental. If physicalism is true, it seems that the ultimate explanation of M’s belief that physicalism is true will mention only neural phenomena and/or more fundamental physical constituents. There will be no mention in that explanation of anything that is ultimately and irreducibly mental. So, even if there are irreducible contents of apprehensions and beliefs which are physically realized…physicalism entails that M believes that physicalism is true, not because his apprehensions of irreducible contents ultimately cause his belief with it irreducible contents but because physical (neural) realizers of those apprehensions causally produce physical realizers of that belief. In short, physicalism seems to entail that apprehensions of contents are explanatorily impotent. Given the truth of epiphenomenalism and the explanatory impotence of apprehensions of contents, why should any of us try to reason with other about anything with the hope of changing their beliefs by having them apprehend contents of conceptual entities (Goetz and Taliafero, 4)?”
This important and subtle “argument from reason” (AFR) must be explained carefully: A common view of rationality holds that what makes our beliefs rational is that we base them on reasons. That is, you rationally believe that P when, and only when, your belief that P results from having fairly considered the reasons for (and against) P and it seems to you that the reasons, on balance, are sufficient for the truth of P. For instance, if I want to know the capital of Mongolia, I pull down my atlas and see that the capital of Mongolia is Ulan Bator. My recognition that a standard reference book, which would be very unlikely to be wrong about such a fact, tells me that the capital of Mongolia is Ulan Bator seems to me sufficient reason to accept that claim. Hence, my belief is rational. The essence of this account of rational belief is that one irreducibly mental event, belief that P is explained by another irreducibly mental event, the apprehension of the reasons for P and their sufficiency for the truth of P.
If you ask Melnyk why he accepts PRM, then, like anyone else, he will give reasons that he holds are sufficient for the truth of his claim. Let’s call those reasons R1, R2, R3…Rn. Goetz and Taliafero argue that if PRM is true, Melnyk cannot hold PRM because of reasons R1, R2, R3…Rn. Suppose that Melnyk apprehends reasons R1, R2, R3…Rn (where we will assume that those reasons include the recognition that the other reasons are jointly sufficient for the truth of PRM). It follows that, since PRM is assumed true, the cause of Melnyk’s belief is not his mental apprehension of those reasons, but the physical realization of those mental apprehensions in his neural states. This is because, if PRM is true, the mental state “belief that PRM is true” is fully realized in a physical (neural) state. Further, that neural state is caused by other neural states, namely, the physical realizations of the apprehension of reasons R1, R2, R3…Rn.
The upshot is apparently that, on PRM, the mental act of understanding a reason is an epiphenomenon of the physical cause. To say that A is an epiphenomenon of B means that B causally determines A, but A does no causal work, either back on B or on anything else. So, on PRM it cannot be the mental act of understanding per se that explains the belief; rather, it is the physical realization of that act that does all the causal work. The mental act therefore just seems a useless appendage, an epiphenomenon. Hence, if PRM is true, then Melnyk cannot believe the truth of PRM because of the reasons he cites. Melnyk does not believe because of those reasons. Instead, his belief was caused by a sequence of neural, i.e. purely physical, events in his brain. But how can a belief be rational if it is not based on reasons? Melnyk’s belief that PRM is true seems to be like the breaking of a glass bowl when it is dropped onto a hard floor. Both belief and breakage seem to be caused by brute, blind force (to indulge in a bit of rhetoric), so neither the belief nor the broken bowl can be explained in terms of reasons.
It seems to follow from this argument that the truth of PRM precludes any rational basis for believing that PRM is true. This is because the truth of PRM precludes the possibility of having any reasons for believing it because it relegates all causes of belief to a sequence of physical causes. Surely, it seems, there must be something profoundly and irremediably wrong with a theory that, if true, insures that it cannot be rationally believed to be true!
I think that the AFR articulated in the above few paragraphs is Goetz and Taliafero’s strongest argument. However, I do not think that Melnyk replies to it adequately so I will now say what I think is wrong with it.
First, note that Goetz and Taliafero’s arguments, and practically all arguments against the MTB thesis, are a priori in nature, whereas the arguments for MTB are mostly empirical. Historically, a priori arguments have fared very poorly when opposed to empirical arguments. Philosophers will draw an a priori line in the sand and scientists will gleefully jump over it. The dismal track record of a priori claims against empirical ones provides some reason to doubt the cogency of arguments like those of Goetz and Taliafero.
Further, human beings would be most unfortunate if in fact a theory as important as PRM were true and could not be rationally believed. Goetz and Taliafero appear to concede that PRM could be true, but they hold that the truth of PRM would preclude rationally believing it by our standards of rational belief. However, if our standards of rational belief are such that they can preclude us from rationally believing an important theory that (we are assuming) is in fact true, then perhaps our standards of rational belief are deficient. Standards of rational belief are supposed to permit, not preclude, rational belief in true theories. If PRM is true—and, again, Goetz and Taliafero apparently concede that it could be—then this is a very important truth and there needs to be some way that we can rationally believe that it is true.
A reliability account of warrant would seem to fill the bill. According to reliabilism, all that matters is whether a belief-forming process reliably generates true beliefs. A belief that is formed by a reliable process is warranted and therefore a rational belief. The nature of the process is irrelevant. If I can reliably form true beliefs by rolling a pair of magic dice, then rolling the dice confers warrant on my beliefs. If we accept reliabilism, then it does not matter if Melnyk is caused to believe that PRM is true by a physical process. It only matters that the process was reliable in generating true beliefs, and the reliability of physical belief-forming processes can certainly be accommodated by PRM and would seem to generate no self-referential problem. That is, there could be reliable processes causing the belief that PRM is true.
Some might object that precisely the problem with a reliability theory is that its account of warrant runs plainly against some of our deepest intuitions about rationality, such as that beliefs are rational only if they held because of the reasons for them. But what is the worth of such intuitions when they are opposed by successful theory? But other intuitions seem to go the other way. If we hold that a belief is rational only if it is held because of reasons that we apprehend and duly consider, then this entails that most of our beliefs are irrational. Certainly all of our perceptual beliefs would be. I see a cup on my desk and immediately believe that there is a cup on my desk. Apprehending reasons has nothing to do with it. It would be highly counterintuitive to say that all of our perceptual beliefs are irrational. The same thing holds for many beliefs based on testimony. As soon as my wife tells me that it is raining again I immediately believe that it is raining again. I don’t weigh her credibility against my background beliefs or anything like that. I immediately, and rationally, accept it.
Perhaps Goetz and Taliafero mean only that theoretical knowledge is rational only if we get it by apprehending and a set of reasons and recognizing the sufficiency of their support for that theory. So, let’s cut to the chase and ask whether reasons would be epiphenomena on PRM, useless danglers that have no explanatory role in accounting for our beliefs? Not at all. In fact, it seems to me that to think that reasons would be epiphenomenal given PRM is to fail to take PRM seriously and to continue to think in dualistic terms.
Let’s begin by reviewing what it means to say that the mental is physically realized. PRM first defines the mind in functional terms; a mind is anything that does mental stuff. It then identifies the human brain (or, technically, certain physical subsystems of the brain) as the object that, for human beings, performs the function of doing mental stuff (including rational thought). At bottom, then, PRM is a theory about how we think; we do it with our brains. We have a mental system fully realized in our mental organ, the brain, just as we have a digestive system fully realized in the organs of digestion. The functioning of our mental system—those orderly, causally-linked patterns of neuronal firings—is how we think, just as the functioning of our digestive system—peristalsis, the secretion of digestive juices, etc.—is how we digest. Those neural processes in our brains are not a more fundamental reality to which thought can be reduced. They are thought itself—the genuine article. Further, the fact that we think with our brains does not make thought any less real, significant, or explanatory than it is on dualism.
Let’s imagine a case of simple inference by modus ponens: Upon arising in the morning I look out the window and see that the streets are wet. I infer that it rained overnight. Generally, that inference would be immediate, but I have not had my coffee yet, so my thinking process is slow. Let’s imagine that I think it out step by step: “I see that the streets are wet. I know that if the streets are wet, then it rained last night. Therefore, it rained last night.” According to PRM, what just happened here? What caused my belief that it rained last night? That belief, “it rained last night,” is neurally realized and, of course, its proximate cause was other neural events. However, those other neural events were events of a very special sort; they were also the thoughts “the streets are wet” and “if the streets are wet, then it rained last night.” So those physical events were also mental events—because the physical events are the doing of the mental events—and so an equally good explanation is that my belief was based on my reasoning validly in accordance with modus ponens.
Given PRM there are two ways of individuating a thought (speaking precisely we should say “a thought token,” but for simplicity I will just say “thought”). We could individuate it by indicating that a particular thought-content was entertained by a particular brain at a given time, e.g. “At time T1 Parsons thought ‘the streets are wet.’” Or we could individuate it by a specifying a particular set of neural events in a particular brain, e.g. “At time T1 this particular pattern of neuronal firing occurred in Parsons’ brain.” But just because we can individuate something in two different ways does not mean that we are individuating two different things. According to PRM, it is one and the same thought that is individuated in both ways. The neural event is the mental event. Thinking “If the streets are wet, then it rained last night; the streets are wet; therefore it rained last night” just is a causally connected series of neural events.
The upshot is that physical realization does not render the mental an epiphenomenon. On the contrary, it is the physical realization of the mental that “empowers” one mental event to cause another mental event. It is in virtue of their physical realization that mental events can cause other, physically realized, mental events. But doesn’t this mean that, as Goetz and Taliafero insist, it is the physical that does all the causing and the reasons are impotent? No, because, again, the physical causing of my belief and the being convinced by reasons are one and the same thing. The physical causing is the mental causing; that is what PRM means. In short, PRM holds that being convinced by reasons is something we accomplish with our brains.
I think that Goetz and Taliafero read PRM as a thesis of the one-way causation of the mental by the physical, rendering the mental into an epiphenomenon. But this is wrong. Melnyk is not saying that the physical produces the epiphenomenal mental like a car engine produces useless noise. It seems that Goetz and Taliafero misconstrue PRM because they continue to think in dualist terms. Dualism must regard the mental and the physical as two opposite and irreconcilable properties, whereas PRM erases that distinction and asserts that the mental is something that special physical things can do. If the thought that mental and physical as mutually exclusive categories is deeply entrenched for you, the claim of PRM will be hard to understand, much less accept.