Sonya Bahar and I have recently contributed to a large volume collecting arguments against the afterlife, edited by Michael Martin and Keith Augustine. William Hasker just reviewed it for NDPR. IMHO the review is not up to the usual NDPR standards.
Hasker dismisses the portion of the volume where our essay occurs as follows: “Non-specialists will find new and interesting details here, but the overall picture will be familiar to those who have followed the progress of the brain sciences. It is crystal clear that, in normal human life, mental function is dependent in an intimate and fine-grained way on brain function.”
Hasker does not engage in detail with any of the essays in the collection, with the partial exception of the essay by Augustine and Yonatan Fishman. His chief complaint is that while Augustine and Fishman correctly argue that the evidence that the mind depends on the brain impugns Cartesian dualism, there are other forms of dualism–such as Hasker’s “emergent dualism”–that, he claims, are consistent with such evidence.
As it turns out, Bahar and I explicitly argue against all forms of substance dualism. We don’t mention Hasker but we explicitly mention non-Cartesian dualism, of which his view is a version. In a nutshell, our argument is that mental functions take place within the brain in a way that rules out all forms of substance dualism. Neural activity is necessary for mental functions. Therefore, without a functioning brain, no mental functions are performed. (Hence, no mental life after brain death.)
One more point. Later in his review Hasker argues as follows:
If causal closure [of the physical] obtains, then evolutionary epistemology cannot be the explanation for human rationality. The reasoning is simple and compelling. If causal closure is true, then everything that happens in the brain has its complete explanation in prior physical events, no doubt mainly earlier brain-events. But this means that prior mental events play no role in determining the state of a person’s brain — and therefore, they play no role in the organism’s behavior. It follows, furthermore, that mental events and processes are irrelevant to behavior and are thus invisible to natural selection, which can only operate on physical structures and physical behavior. (emphasis original)
The only way that I can make sense of this argument is that Hasker begs the question by assuming that mental events are metaphysically independent of brain events–precisely the kind of claim that Bahar and I refute in our essay.
I almost choked when I read the passage you quote… very glad your response is now online!
thanks, Dan!
Congrats that book looks very cool, can’t wait to read some of these chapters.
Do they do peer review on these book reviews?
That quote is odd: it seems he is pushing something like Kim’s causal exclusion worry, but assuming the only solution is antimaterialistic. Instead of claiming, “The reasoning is simple and compelling”, he’d probably be better served to acknowledge the controversy, state his doubts, and move on.
Thanks, Eric!
Book reviews are not peer reviewed (nor should they be).
True, Eric. Perhaps Kim showed nonreductive physicalism to be a rather unstable position, and whether one then uses it as a moden ponens for reductivism or a modus tollens for nonphysical monism or some type of dualism will always be called begging the question from the other point of view.
I was rather stunned by the following quote from the NDPR review: “There is some discussion of the mind-body problem, but much of it could be termed cursory. The authors feel little need to engage seriously with sophisticated contemporary dualists, and they hardly pay attention to criticisms and objections to materialism…” A good part of my chapter with Yonatan Fishman deals with at least some of them, not to mention parts of other chapters (in a book over 600 pages). And I’m still not quite sure what Hasker counts as a “sophisticated” contemporary dualist. If we are right, then virtually every form of dualism is false, not merely substance dualism. Yeah, overall, a rather weak review I thought.
Thanks, Rocco. I completely agree.
My thanks to Keith Augustine for calling this site to my attention. I shall respond briefly to the comments from Gualtiero Piccinini. Let me remind all concerned that, given a long and complex book and limited space for a review, it is inevitable that the individual essays will not be discussed in depth. First, my point about emergent dualism (and Thomistic dualism) is that on these views it is not unexpected that the brain will be involved in mental processing in a fine-grained way, something that does not seem to be expected given Cartesian dualism. Piccinini and Bahar state, “What the evidence shows is that mental functions take place in the brain in a way that rules out substance dualism” (137). I don’t challenge the localization evidence, or the evidence showing that, in the normal circumstances of human life, failure of brain function in the relevant respect results in failure to perform the associated mental activity. This raises the question, is there any possible way in which such mental activity could be supported subsequent to the death of the brain? The answer is yes. There could, for instance, be a replacement brain. Or perhaps God can sustain the mind’s life in some other way, a way we are unable to imagine in detail. But perhaps the probability of such scenarios seems to you to be vanishingly small? If so, this underscores another point made in my review, namely the importance for the overall issue of broad worldview considerations. I would expect that most, if not all, of the commentators on the blog are philosophical naturalists and non-theists, and have believed for some time that there is no afterlife. You then find the arguments in the book to be compelling, and my reservations inconsequential. That’s fine. But if this is all the book is intended to accomplish, it’s a pretty modest objective. It’s the equivalent of what religious folk sometimes term “preaching to the choir.” For those who don’t belong to the naturalist church to begin with, the situation may look quite different.
Piccinini does miss the point of the argument he cites. The argument does not assume that “mental events are metaphysically independent of brain-events.” This should have been evident from the penultimate paragraph, in which I develop the argument on the assumption that mental events are identical with physical events. The point is, that natural selection can operate only on the physical characteristics of those events, selecting the events (or rather, the associated brain-structures) that lead to behavior conducive to survival and reproduction. This, however, provides no explanation whatsoever of the fact (if it is a fact, as we all constantly assume), that the intentional content of the selected events corresponds even approximately to the actual state of the world. And yes, one can evade this argument by adopting a reductionist or eliminativist view in which there simply are no mental characteristics of events distinct from their physical characteristics.
William,
Thanks for your note and for reviewing the book.
In our chapter, Bahar and I argue against “replacement brains” and other ways “God can sustain the mind’s life” in a substantive appendix to our paper. So we are not just preaching to the choir while ignoring the literature favorable to the afterlife.
Thanks for clarifying your argument about causal closure and evolutionary epistemology. If mental properties are metaphysically dependent on physical properties, as you seem to agree they are, there is a legitimate question as to whether natural selection can operate on them. Whether natural selection can operate on them depends on the exact nature of their relation to physical properties. Surely there are possible relations such that natural selection cannot operate on mental properties–this is what you seem to be relying on. Equally surely, though, there are possible relations (including non-reductive relations) such that natural selection can operate on mental properties. This latter type of relation is the kind that sane naturalists should posit between mental and physical properties. The devil is in the details and I’m not going to enumerate all the possible options and their pros and cons here. The bottom line is that, if mental properties are metaphysically tethered to physical properties, in principle nothing prevents natural selection from operating on mental properties.
Much could be said in response to the substance of the NDPR review, so I will try to keep my own comments here focused on just two points:
First, Bill states that the tight dependence of mental functions on brain functioning is unexpected on Cartesian dualism, but not so on non-Cartesian dualisms. But this is false: my own Dualist’s Dilemma chapter with Yon should make clear that Bill’s own “emergent substance dualism” is just another way of adding ad hoc assumptions the independence thesis (the view that having a functioning brain is NOT a necessary condition for human mental life) in order to accommodate the evidence that we actually find. Emergent substance dualism is just a version of what I have dubbed “the dependence-looking independence thesis,” so named based on the “proverb” that “if it looks like a duck, swims like a duck, and quacks like a duck, then it’s probably a duck.” If all of our best evidence most parsimoniously points toward the truth of the dependence thesis, we ought to accept that thesis rather than some version of the independence thesis that can be contorted to “fit” the same evidence. For as I wrote just after introducing the term “dependence-looking independence thesis”: “if drastically diminished mental functioning following severe brain damage provides just as good evidence for the independence thesis as subsequently unaffected or considerably enhanced mental functioning would have provided…, it is hard to see how the independence thesis can stake a claim as an empirical hypothesis at all. It parallels the unfalsifiable Omphalos hypothesis that God created the world to *look like* it had an enormous prehistoric past, but really is less than ten thousand years old.” (p. 246)
For if we have two independent substances in interaction, with their own principles of operation–which we do on ANY version of interactionist substance dualism–then it straightforwardly follows that the operations of one of the substances is going to be largely *independent* of the operations of the other. Because of their interaction, their operations won’t be wholly independent (e.g., what the eyes take in will affect one’s thoughts), but independent enough, say, that one’s moral judgments ought not be compromised by PCP intoxication. But of course they *are* so compromised. Thus, in all probability, the independence thesis is false.
Now as I understand it, emergent substance dualism no less has the *implication* that mind and brain are two different, interacting things undergoing separate processes as any other version of the independence thesis. The processes of one can of course loosely affect the other–that is, to some extent. But to what extent? My argument is that brain processes affect mental processes so profoundly (in, for example, the case of PCP intoxication) that, in all probability, mental processes must be brought about by brain processes, and so cannot exist without them–in which case there is no mental life after brain death, to steal Gualtiero’s title. If an independently existing mental substance “emerges” from the brain after a certain point of human development, as it does on emergent substance dualism, then it exists independently of the brain, with its own principles of operation, from there on out–much like a newborn does once it “emerges” from its mother’s womb (even if it still “interacts” with its mother through its umbilical cord). If that’s the case, PCP intoxication ought not compromise one’s moral judgment on any version of the independence thesis, including emergent substance dualism. But of course it does, and so the latter is probably false.
So Bill misses the point when he writes here: “This raises the question, is there any possible way in which such mental activity could be supported subsequent to the death of the brain? The answer is yes.” In both the Introduction and “The Dualist’s Dilemma” I embrace this very answer, but qualify it thus:
“[Survivalists] miss the point that such arguments are probabilistic, and so offer inadequate explanations about how survival might *possibly* occur despite the enormous amount of strong prima facie evidence against it. Since the mere *logical possibility* of survival does nothing to dispel its empirical improbability, these responses simply do not do justice to the neuroscientific/biological case for extinction.” (p. 5)
“Our concern should not be with what is merely possible, but with what is most likely to happen given what we know about the world.” (p. 11)
Second, Bill goes on to write: “But perhaps the probability of such scenarios seems to you to be vanishingly small? If so, this underscores another point made in my review, namely the importance for the overall issue of broad worldview considerations.”
But why bring worldview considerations into it at all? One can check various theories in psychiatry against the data according to scientific principles without introducing the sorts of “worldview considerations” that might further count against those theories if one were, say, a Scientologist. One can evaluate those theories on empirical grounds alone, ignoring the “worldview considerations” that a Scientologist might want to introduce. Since those “worldview considerations” are extraempirical to begin with, and there are plenty of empirical consideration apart from them to shed light on the subject, I think it justified to give “worldview considerations” short shrift and just focus on the data. One needn’t “belong to the naturalist church” to recommend this approach; surely Francis Collins isn’t defaulting to naturalism simply because he doesn’t bring “worldview considerations” into his genetic research. (And surely neglecting theological arguments for geocentrism, which no doubt existed, would have been no real weakness in making an empirical case for heliocentrism hundreds of years ago.)
Indeed, one need not even adopt any particular theory of mind to advocate the dependence thesis; it is compatible with reductive materialism, token identity, property dualism, dual-aspect monism, Russellian monism, and even at least one form of interactionist substance dualism–what C. D. Broad called compound theory. (It is notable here that neither of the two most prominent advocates of the sort of mortalistic argument I make–David Hume and Bertrand Russell–were “materialists” in the philosophy of mind. Their reasons were empirical.)
The dependence thesis nevertheless rules out any form of survival positing that we have a separable soul that could survive death. Thus I think that it misses the mark to complain that The Myth of an Afterlife doesn’t dive into the mind-body problem more than it does; there are plenty of philosophy of mind textbooks that do that already, and since there is no necessity in doing so at all to make a case against personal survival, one could simply cite works that cover these issues elsewhere in an endnote if one wanted.
A quick response to Piccinini; more later (perhaps) for Augustine.
Your article argues against replacement brains with no soul. As you know, there is a literature supporting this hypothesis, but I agree that it doesn’t work. My view is that there is indeed a soul; the replacement brain will fill the same role played by the original brain prior to death.
I take it you agree that natural selection can operate directly only on physical events, processes, and structures. What is needed, then, is a naturalistically acceptable account that guarantees that events, processes, and structures that are conducive to survival tend to be accompanied by mental contents that correctly represent the world. If there is a plausible account of this sort, then that argument of mine will go by the wayside. (I do have others!) But as you say, the devil is in the details, and I need to see some of those details before I am prepared to concede the point.
Dear Prof. Hasker, Single celled organisms sans brains can detect and pursue prey. Amazing what a single cell can do. Worms with a little over 100 neurons and some sensory organs can detect their environment to a far wider degree and react in a far more diverse manner to their environment than a single cell. So it is not improbable that mammals as a whole with far larger and more diversified brains, including primates and humans with billions of neurons and trillions of electro chemical connections between them, and input from sensory organs, might have a very wide detection and inner sense of their environment and react in a far wider variety of ways than say, single celled organisms, or worms with a little more than 100 neurons, or even living species of great apes.
Dear Prof. Hasker, I don’t think the argument from reason that you shared above, as endorsed by Plantinga and Reppert, is much of a conundrum since it seems to rely on the questionable notion that a words equal things, including the word “reason,” and also ignores different holistic levels of interaction. for instance, humans are not interacting with or perceiving individual atoms, one at a time, but sensing and interacting with whole scenes made up of atoms. And it is these broader sensations of the whole body brain mind system which we sum up with wants, needs, desires, that drives the entire organism. In our case we also have a drive we call curiosity. I explain is view more fully, along with questions concerning the differences between words and things, maps and territories, models and reality (including a brief discussion of mathematical models) here https://edward-t-babinski.blogspot.com/2011/01/prior-prejudices-and-argument-from.html
William,
Thanks for your query. You ask whether “events, processes, and structures that are conducive to survival tend to be accompanied by mental contents that correctly represent the world.” “Mental contents” is a rather contested and somewhat nebulous term so I will avoid it for now.
Here is how I would reframe and answer your question. Complex organisms adapt to their environment, in part, by collecting and processing information about it. In the present sense, an internal variable of the organism carries information about X just in case it correlates reliably with X. Information about X is accurate to the extent that the correlation with X is precise and reliable. Information in this sense is a physical quantity (in a broad sense). The more accurate the information and its processing, the more adaptive it is (other things being equal). Natural selection can act on organisms based on the information they collect and process and how accurate it is.
An important project in the philosophy of mind is aimed at reconstructing useful notions of representation and mental content based on something like that above notion of information (cf. Dretske, Millikan, Fodor, Papineau, Ryder, etc.). That project is a work in progress and therefore somewhat controversial. We don’t need to assume that that project will completely succeed to everyone’s satisfaction in order to see that complex organisms are naturally selected, among other reasons, for carrying and processing accurate information about themselves and their environments.
Keith Augustine doesn’t like my mind-body theory, emergent dualism. He’s entitled to his opinion, but some of the things he says about my view just aren’t true. He says the view is “just another way of adding ad hoc assumptions [to] the independence thesis (the view that having a functioning brain is NOT a necessary condition for human mental life) in order to accommodate the evidence that we actually find.” That is simply false. When I first formulated the view, in 1974, I was not especially concerned with anti-survivalist views like Augustine’s. I have various arguments for the view that do not depend on detailed neurological evidence of the kind that he cites. Emergent dualism is not (yet!) one of the more widely held mind-body theories, but some of the philosophers who have held it (or very similar views) should give one pause. An early advocate was Karl Popper; more recently, there is Peter Unger – neither of them religious, neither of them believers in an afterlife. Emergent dualism stands on its own metaphysical feet, regardless of afterlife arguments.
Here is a central argument of Augustine’s:
“For if we have two independent substances in interaction, with their own principles of operation–which we do on ANY version of interactionist substance dualism–then it straightforwardly follows that the operations of one of the substances is going to be largely *independent* of the operations of the other. Because of their interaction, their operations won’t be wholly independent (e.g., what the eyes take in will affect one’s thoughts), but independent enough, say, that one’s moral judgments ought not be compromised by PCP intoxication. But of course they *are* so compromised. Thus, in all probability, the independence thesis is false.”
This, I submit, amounts merely to a subjective, and contestable, judgment about what degree of mutual dependence is possible for the functioning of interacting substances. One might argue that the mental functions of a mathematician doing calculations on a computer are sufficiently independent of the computer’s workings that the result ought not to be affected by a glitch in the programming – but of course, it can be. Emergent dualists take the facts of dependence as they find them; these facts are not inconsistent with their mind-body theory, in spite of Augustine’s opinion.
Most egregious, however, Is his apparent attribution to me of the view that “drastically diminished mental functioning following severe brain damage provides just as good evidence for the independence thesis as subsequently unaffected or considerably enhanced mental functioning would have provided.” This is patently absurd, and I have never said or suggested anything of the sort. My view is that the neurological evidence does put pressure on mind-body dualism – even emergent dualism – and on the case for an afterlife. I don’t, however, accept that this evidence is necessarily decisive. In a sense, Augustine and I agree on this; he acknowledges that there are possible ways in which mental activity could be supported subsequent to the death of the brain. Whether such possibilities deserve consideration depends on whether one has serious reasons (not merely wishful thinking) for believing in an afterlife. And this brings me to my second main point.
One of my complaints about The Myth of an Afterlife concerns the book’s relative neglect of broader worldview concerns – especially mind-body issues, which are discussed in what I contend is a cursory and unsatisfactory fashion, and issues concerning theism, which are not discussed at all. Augustine replies, “why bring worldview considerations into it at all?” One reason for bringing them in is the strong correlation between worldview beliefs and a belief or disbelief in an afterlife. Among Western philosophers, the strong majority of believers in an afterlife are theists, and a strong majority of disbelievers are atheists. (In the East, the situation is complicated by the affirmation of reincarnation in non-theistic religions.) A majority of afterlife believers favor some variety of mind-body dualism, and disbelievers are mostly materialists of one stripe or another. These correlations may be less strong than for theism and atheism, but they are still impressive. (Hume and Russell may have been phenomenalists rather than materialists; I take it that phenomenalist views don’t get a great deal of traction at present.) Now, all of these philosophers may simply be confused in seeming to perceive a relevance of worldview considerations to the afterlife. All the same, the confusions (if that is what they are) are sufficiently widespread to merit investigation. But I don’t think the correlations are evidence of confusion: in particular, theism enhances the probability of an afterlife in a number of different ways, and the relevance of dualism is equally obvious.
Augustine, however, thinks we should ignore all this and just go with what seems most probable, based on empirical evidence alone. If this isn’t merely an idiosyncratic prejudice, it must represent the view that empirical, scientifically verifiable evidence is the only way in which we can gain knowledge of the world. And this, of course, is a cardinal tenet of naturalism, and as such is question-begging. (Quine even said that it just is naturalism; I think he was wrong about that, but it certainly is a key component of naturalism.) In any case, I don’t think that is what is really going on in the book. On the whole, I think most of the contributors are taking atheism and materialism as default assumptions. They are entitled to do this, but it underscores my contention that the book is an anti-survivalist polemic rather than a balanced investigation of the issues concerning an afterlife.
One of Keith’s examples strikes me as especially intriguing. I fully agree that Francis Collins did not, and should not, bring worldview considerations into his work at the human genome project. However, I think you will find that in other contexts – for instance, the comprehensive issue of the nature of human beings, or the point and meaning of human life – Collins’ conclusions are deeply affected by his devout Christian faith. And this, I have no doubt, includes his beliefs concerning the afterlife.
Just for the record, I don’t *dislike* emergent substance dualism; I merely think that it is likely to be false. It attempts to make room for tight mind-brain correlations that are more parsimoniously explained by the dependence thesis, since such correlations straightforwardly fall out of the truth of the dependence thesis.
Bill might not have been thinking of these correlations as evidence against dualistic survival in 1974, but many people before him have done so, and by 1983 Bill clearly elucidated the worry in his essay “Brains, Persons, and Eternal Life,” writing (among other things): “If … the mind or soul is generated by the brain and is dependent on it in all the ways already emphasized, how can it fail to perish with the brain?”
I think we’ll just have to agree to disagree on the idea that, all else held equal, two separate things performing separate processes will function largely independently of one another–and that where they are so tightly bound together, that there is anything more than a negligible probability that one could survive the destruction of the other.
To be fair, my comment about independence thesis proponents committed to holding that “drastically diminished mental functioning following severe brain damage provides just as good evidence for the independence thesis as subsequently unaffected or considerably enhanced mental functioning would have provided” was aimed at filter theory advocates like William James, Neal Grossman, and Chris Carter, who explicitly argue that the neuroscientific evidence could never count against their views, come what may. I did not have emergent substance dualism specifically in mind in making that point, though I think it applies by extension to any independence thesis proponent who denies that the existing neuroscientific evidence counts against the independence thesis (or, if you like, counts in favor of the dependence thesis).
To Dr. Hasker,
My question concerns your two objections to the premise “Nothing that goes on in the brain violates the predictions of physical science.”
You claim that the empirical evidence isn’t strong enough to warrant affirming the premise at this point in time. I assume, however, that you believe that the empirical evidence could be strong enough in the future.
My question is whether you believe that the possible empirical evidence should be taken as more compelling than your conceptual objection concerning evolutionary epistemology. If we know everything that we can know about the brain, and according to our observations, the laws of physics aren’t broken, would the conceptual objection be overridden even if a satisfying rebuttal hasn’t been developed?
For Ed Babinski: I don’t think the version of the argument from reason I presented confuses words with things, nor do I see that the other considerations you mention constitute an answer to the argument. If you think they do, please try to be more explicit.
For Gualtieri Piccinini: Thank you for your reply. For my purposes, your key statement is: “Information in this sense is a physical quantity (in a broad sense). The more accurate the information and its processing, the more adaptive it is (other things being equal).” Considering “information” in this way, I have no objection to your statements. However, this completely leaves out of account our *conscious experience* of apprehending the world as being so-and-so. It is only through such conscious experience that we (in the ordinary sense) “know” or “understand” anything. If your philosophy of mind does not take such conscious experience into account, it is unable to register the argument I’ve presented. If you translate “conscious experience” into a physical quantity, as in your quotation above, this fundamentally distorts and misrepresents my argument.
To adapt an example I’ve used before: Suppose a family of primitive hominids is threatened by a saber-toothed cat. Assuming the closure of the physical, natural selection may be able to guarantee that the physical information (in your sense) in their brains corresponds to the presence of a dangerous predator, and triggers a protective reaction, such as climbing a tree. But we have in this *no explanation whatever* of the fact that the hominids’ conscious experience is one that can be transcribed as “Let’s get out of here before that cat arrives,” rather than, “Isn’t this a delicious meal of baboon meat?”
For Keith Augustine: Certainly the notion of mind-brain correlations as evidence against dualistic survival was in play before 1974. My point was merely that emergent dualism is a metaphysical hypothesis on its own merits, not a desperation move to counter anti-survivalist arguments. Once again, the examples of Popper and Unger are telling here.
I think you are right that we must agree to disagree about the extent of functional interdependence that may be possible for two distinct substances.
Thanks for clarifying the source of the remark to the effect that “the evidence doesn’t make any difference.” In context, it looked as though you were attributing that thought to me; I’m glad to learn that you were not.
For Victor: Nice question! I think that sometimes we may be able to imagine evidence of a certain sort being produced, and yet we may be justifiably confident that such evidence will never in fact be produced. For example: if someone could predict, accurately and in great detail, the behavior of an ordinary person living in ordinary circumstances over an extended period of time, this would seriously conflict with my belief in libertarian free will. Since I am strongly convinced that we do have free will, I am confident that such evidence will never be produced. But suppose it were produced? If I were convinced that this had been done (and I admit I would be hard to convince), I would have to consider that there might be something wrong with my arguments for free will. But to say that is merely to admit that I am fallible, which is not front-page news. The key point here is, that not everything that is imaginable is metaphysically possible. I think you can see how these considerations apply to the point we are discussing.
I think there may be some limits on what questions can reasonably be considered to be empirical questions. Let’s take the Freudian view of religious belief as an example. According to Freudians, (and many other atheists as well) even those who think they believe in religious beliefs for reasons are really believing them for emotional reasons, and the “arguments” they provide are merely rationalizations. But why stop with religious beliefs? Isn’t it possible that we don’t believe any of our beliefs for reasons, but rather, we believe them for other reasons. If we looked at how we actually form beliefs, couldn’t we discover that, in fact, we never believe anything for the reasons we think we do? Is the statement “No one ever believes anything for a reason” at least possible? I like to refer to this position as hyper-Freudianism.
Unfortunately, such a position involves what Lynne Rudder Baker calls cognitive suicide. If a hyper-Freudian is asked why she believes in hyper-Freudianism, and she offers evidence for her belief, then by offering such evidence she falsifies hyper-Freudianism.
Now, I actually think that if categories are not fudged, and the material is defined, as it often is, in terms of the absence of the mental, then materialist theories of mind actually entail hyper-
Freudianism. It results in a proof that there are no proofs, which has to be nonsense.
It follows that no account of the universe can be true I unless that account leaves it possible for our thinking to be a real insight. A theory which explained everything else in the whole universe but which made it impossible to believe that our thinking was valid, would be utterly out of court. For that theory would itself have been reached by thinking, [22] and if thinking is not valid that theory would, of course, be itself demolished. It would have destroyed its own credentials. It would be an argument which proved that no argument was sound–a proof that there are no such things as proofs–which is nonsense.-C. S. Lewis
I appreciate all the dialogue!
Piccinini: Your posts were very intriguing. I’m persuaded by Plantinga’s Evolutionary Argument Against Naturalism (EAAN), so I’m always interested in criticisms of it. But before I get there, I wanted to express appreciation for your open-mindedness. Though Hasker has reservations about the neglect of Worldview Considerations in his response to Augustine, I appreciate your confession of not preaching to the choir, and not ignoring after-life literature.
Your response to Hasker’s EAAN is that if mental properties are ‘tethered’ to physical properties, then natural selection can operate on mental properties indirectly through the physical properties. In this scenario, you propose a ‘non-reductive relation’ subsisting between mental and physical properties through which natural selection can operate. Hasker responds by acknowledging the possibility of such a relation, but that natural selection needs to affect physical properties in such a way that the mental properties elicit adaptation involving survival and ‘true’ apprehension of reality/environment.
It’s at this point you make very interesting points. You propose to reframe the question by construing information quantitatively. In that context, an organism’s adaptation amounts to collecting/processing information about an environment relative to an ‘internal variable’. This ‘internal variable’ in the organism collects/processes information about an environment only if such information ‘correlates’ with the environment. Correlation in this case entails ‘accuracy’ of information. The greater the accuracy of the information, the better an organism’s adaptation. Natural selection could simply be a function of said accuracy. This is the story that should underlie the project of reconstructing terms in philosophy of mind like mental content and representation.
Hasker responds by disagreeing that information should be understood in the quantitative sense, because information in the quantitative sense doesn’t take into account the role ’conscious experience’ plays in EAAN. Conscious experience involves, among other things, knowing/understanding things in an environment. Hasker illustrates with an example involving hominids threatened by the presence of saber-tooth tigers in their environment. If the causal-closure thesis is true, then natural selection ensures accurate information regarding their environment, where ‘accurate information’ means ‘correlation between information-content and environment-content’. But according to Hasker’s EAAN, accuracy of information is not necessary/sufficient to/for understanding/knowing that the proper interpretation of information-content in response to environment-content is that one should should seek protection from a predator, rather than running toward the predator for food (other things being equal). Therefore, natural selection could ensure accuracy of information to the utmost, but that wouldn’t ensure proper interpretation of the accuracy of information in the form of true beliefs.
Augustine: Your contributions were also very helpful in understanding your criticisms of Hasker’s Emergent Substance Dualism (ESD). You voice concerns regarding the alleged expectation of mental functioning depending on brain functioning. I do agree with Hasker that dualists in general (or, those that I’ve read) don’t add ad hoc assumptions to accommodate emerging neuroscientific or biological evidence of the dependency thesis. Your direct critique of the independence thesis according to which brain functioning is not necessary for mental functioning is that it falls victim to what you call the ‘dependence-looking independence thesis (DLIT).
You note that philosophers of mind have noticed that diminished brain functioning has affected diminished mental functioning, and that dualists have interpreted this relationship as supporting the ‘independence thesis’ and the thesis that ‘enhanced brain functioning enhances mental functioning’. Though Hasker denies having said this, I do think that your equation of this interpretation with the Omphalos Hypothesis interesting, implying that this version of dualism is not an empirical hypothesis, and so not falsifiable. But I think Hasker is correct in noting that empirical/neurological evidence is not decisive against dualism, since the possibility of survival implied by dualism depends on metaphysical reasons, rather than empirical ones only.
Your other point regards the interaction between two substances implying partial dependence, as evidenced by the effect of PCP on compromising moral judgments. But as Hasker intimates, this partial-dependence point depends on metaphysical considerations not dependent on neurobiological considerations alone. Thus, if mental substance is partially dependent on physical substance in a way analogous to a mathematician partially depending on a computer for solving equations, and the computer glitches, then the mathematician’s operations will be incapacitated, even though the mathematician herself is unscathed. Thus, it could possibly be the case, given the soundness of metaphysical arguments for dualism, that the mental substance will live on after the death of the physical substance in the same way that the mathematician would live on even if the computer on which she conducted mathematical operations were destroyed.
I do think that these so-called metaphysical arguments/reasons are necessarily tied to what Hasker would call relevance of Worldview Considerations to theory adjudication, depending on the theory. You rightly denounce the impropriety of importing such Worldview Considerations to theory adjudication where such importation is not necessary, such as Scientology’s with Psychiatry, or Christianity with Francis Collins’ research with the Genome Project. It seems as if Hasker thinks that the propriety of such Worldview Considerations is partially determined by correlations between belief/disbelief in a worldview and belief/disbelief in a theory such that the degree of such correlations are lopsided enough to be worth looking into. I agree with this. It’s interesting that naturalists/materialists/atheists tend to disbelieve in life after death, and Christians/theists tend to believe in life after death, and it seems prima facie the case that bolstering Christian Theism as a whole increases the probability that life after death will occur.
Thanks a bunch, God bless, and Happy New Year!