Category: Paranormal

AI and Demons

You may remember our 'demonic' discussion from last summer. See  Reading Now: Demonic Foes. The comment thread runs to 61 entries, some of them excellent.

Bro Joe now wants us to read: Satanic AI: ChatGPT gives instructions.

Another topic we ought to explore is the possibility of demonic possession of AI systems. 

According to Richard Gallagher, M.D., "The essence of a possession is the actual control of the body (never the 'soul' or will') of a person by one or more evil spirits." (Demonic Foes, p. 80). Now AI systems do not have souls or wills of their own (or so I argue), but they do have bodies, albeit inorganic.  Might they then host demons?

Gallagher's book is outstanding. So if you think demonology is buncombe, you should study his book and disembarrass yourself of your illusions. 

The Dangers of Psychic Phenomena on the Spiritual Quest

The thoughts of Paul Brunton well presented in a short video. I have been reading him for years. Like Thomas Merton, the man is at his best in his journals. I have read and re-read all sixteen volumes. For some extracts see my Brunton category. 

Saturday Night at the Oldies: Ghosts and Death

Leslie Kean's Surviving Death: A Journalist Investigates Evidence for an Afterlife (Three Rivers Press, 2017) just arrived via Amazon. HT to Vito for recommending it. It looks good. Have book, will blog.  Pressed for time this evening. But not so pressed that I can't scrounge up three tunes.

Highwaymen, Ghost Riders in the Sky

Spiderbait rendition

Blood, Sweat, and Tears, And When I Die

Time for Mark Levin. 

Rod Dreher on Fr. Carlos Martins, Spiritual Warrior

Dreher quotes Martins:

Between these two goals—tempting man and gaining him for eternity—there is another evil desire that the Devil aims to satisfy: the possession of his victim. Possession is the state where the victim is under demonic control from the inside. The demon takes over the body of the one he possesses. During possession, a victim’s consciousness is suppressed, and the demon animates his body as his own. 

Given that demons exist outside of time and space, how can a demon be “inside” someone during demonic possession? While a demon’s lack of physicality frees him of the limitations to which physical objects are subject and gives him access to everything in the physical universe simultaneously, he does not have power over all things equally. When the Devil possesses a victim—and is now “inside” him—the Devil has gained legal jurisdiction over him in such a manner that he can bully and manipulate the victim from the inside. The legal control a possessing spirit has is so great that the body he possesses appears to be his own. 

I'd like to hear more about this legal jurisdiction. If the possessing demon has a legal right to occupy and use the body of the human being who is possessed, from where does the demon get this right? Suppose some children are quite innocently fooling around with a Ouija board. Are they thereby inviting demons into their lives, and granting them the legal right to oppress or possess them?  Would a good God allow these kids to be ensnared in this way? I should think not.  Is there the makings here of an anti-theistic argument from evil? My Ouija board example is quite different in obvious ways from the Faust legend or the story of Robert Johnson at the crossroads, a variant of which is here.

Dreher too is intrigued by the the legal aspect of possession, oppression, and the milder forms of demonic influence. "To me, the most fascinating aspect of this phenomenon is the legalistic one. Every experienced exorcist will tell you that the demons are extremely effective lawyers."  From 'Demons are effective lawyers' it does not follow that effective lawyers are demons, though many will be 'tempted' to embrace that non sequitur. Remember Michael Avenatti? But I digress.

Dreher quotes some more:

An exorcist must focus not on the demon but on why the demon is present. Stated differently, if a demon inhabits someone, he has been granted the right. Demons live and breathe legalism. As long as the demon enjoys the legal right to possess, he is not required to leave because he is inside a dwelling that is his. Just as someone who owns a deed to a property cannot be evicted from it, an exorcist cannot evict a demon from a victim over whom he has gained the right to possess. 

Uncovering demonic rights is challenging and can be the most difficult part of an exorcist’s work. A victim himself often does not know how he has acquired demons. In the case of Jeremy, this was not the case. He knew exactly why he had a demon: he had agreed to a pact with him. But it is often not that easy. An exorcist will probe a victim’s experience, personal history, and psyche to locate the legal claims a demon may have. The demon will do everything he can to remain hidden. 

I plan to return to these questions after I read the book by Martins which I expect to arrive in early December.

Jeffrey Long, M. D. on Near-Death Experiences (NDEs)

Here (under 5 minutes).

'Coded' as used by Dr. Long in this video clip is medical jargon. For a patient to 'code' is for the patient to suffer cardiac arrest. 

It is a mistake to think that if an episode of experiencing is real, then  the intentional object of that episode of experiencing is also real. The question I want to pose is whether Dr. Long is making that mistake. But first I must explain the mistake and why it really is a mistake.

Consider a perceptual illusion.  I am returning from a long hike at twilight. I am tired and the light is bad. Suddenly I 'see' a rattlesnake.  I shout out to my partner and I stop marching forward. But it turns out that what I saw was a twisted tree root. This is a typical case of a visual perceptual illusion.  (There are also auditory, olfactory, tactile, and gustatory illusions.)

What I initially 'saw' is what I am calling the intentional object. The intentional object, the object intended, is distinct from the act  (occurrent episode) of consciousness directed upon the intentional object. Act and intentional object are obviously distinct; but that is not to say that the one can exist without the other: they are, necessarily, correlates of one another.  No act without an intentional object, no intentional object without an act. 

Now not all episodes of consciousness are object-directed, or consciousnesses of something (the 'of' to be read as an objective genitive). But some conscious states of a person are object-directed. These mental states exhibit what philosophers call 'intentionality.'  (Bear in mind that 'intentionality' as here used  is a term of art, a terminus technicus, not to be confused with more specific ordinary-language uses of 'intend' and 'intentionality.') Intentionality, then,  is object-directedness.  One must not assume, however, that every object of an intentional mental state  exists. Some intentional objects exist and some do not. 

Philosophers before and after Franz Brentano have repeatedly pointed out that the intentional object of  (subjective genitive) an object-directed state of consciousness  may or may not exist.  Intentionality, we may say, has the 'non-inference property.'  From 'S is conscious of  an F,' one cannot validly infer, 'there exists an x such that x is an F.' For example, if I am imagining, or hallucinating, or dreaming, or simply thinking about a centaur, it does not follow that there exists a centaur that I am imagining, or hallucinating, or dreaming, or simply thinking about.

In my hiking example, the snake I 'saw' did not exist. But there is no denying that (i) something  appeared to me, something that caused me to shout out and stop hiking, and that (ii) what  appeared to me did not have the properties of a tree root — else I would not have shouted out and stopped moving.  I have no fear of tree roots. The intentional object had, or rather appeared to have, the properties of a rattlesnake. So in this case, the correlate of the act, the intentional object, did not exist. And this without prejudice to the reality of the act. 

If we agree that to be real = to exist extra-mentally ('outside' the mind), then in my example, the visual experience was real but its intentional object was not.

Suppose now that a person 'codes.' He suffers cardiac arrest. Oxygenated blood does not reach his brain,  and in consequence his EEG flatlines, which indicates that brain activity has ceased  and that the patient is 'brain dead.'  Suppose that at that very moment he has an NDE. An NDE is an occurrent episode of experiencing which is, moreover, intentional or object-directed.  The typical intentional object or objects of NDEs include such items as a tunnel, lights, angels, dead ancestors, and the the heavenly realm as described in Long's video, and as described in innumerable similar accounts of NDEs.  But from the occurrence and thus the reality of the near-death experiencing it does not follow that the heavenly realm and its contents are also real.  Their status might be merely intentional, and thus not real,  and this despite their being extremely vivid. 

Yes or no? This is the question I am raising.

Is it logically consistent with the patient's having of that near-death experience that he not survive his bodily death as an individual person who 'goes to heaven'?  Yes it is.   That he had a real experience is not in question. The patient was near death, but he was alive when he had the experience.  He is here to answer our questions. The patient is honest, and if anyone knows  whether he had an NDE, he does. He is the authority; he enjoys 'privileged access' to his mental states. 

But unless one confuses intentio and intentum, act and object, experiencing and the experienced-qua-experienced, one has to admit that the reality of the experiencing does not guarantee the reality of heaven or of angels or of dead/disembodied souls or one's  survival of  one's bodily death.

For it could be — it is epistemically possible that — it is like this. When a patient's EEG flatlines, and he does not recover, but actually dies, then his NDE, if he had one, is his last  experience, even if  it turns out to be an experience as of  heaven. Perhaps at the moment of dying, but while still alive, he 'sees' his beloved dead wife approach him, and he 'sees' her reach out to him, and he 'sees' himself reach out to her, but he does not see her or himself, where 'see' is being used as a 'verb of success.'  ('See' is being used as a verb of success if and only if 'S sees x' is so used as to entail 'X exists.' When 'S sees x' is used without this entailment, what we have is a phenomenological use of 'see.'  Note that both uses are literal. The phenomenological use is not figurative. Admittedly, the point being made in this parenthesis needs defense in  a separate post.)

If this epistemic possibility cannot  be ruled out, then there is no proof of an afterlife from NDEs. In that case we cannot be objectively certain that our man 'went to heaven'; we must countenance the possibility that he simply ceased to exist as an individual person.

Finally, can Dr. Long be taxed with having committed the mistake of confusing the reality of the experiencing with the reality of the experienced-qua-experienced? I think he can. The video shows that he is  certain that there is a heaven to which we go after death, and that the existence of this heaven  is proven by the very large number of NDEs that have been reported by honest people. But he is not entitled to this certainty, and he hasn't proven anything.

Am I denying that we survive our bodily deaths as individual persons? No! My point is merely that we cannot prove that we do on the basis of NDEs.  There is no rationally coercive argument from the reality of NDEs to the reality of an afterlife in which we continue to exist as individual persons.  

Reading Now: Demonic Foes

By Richard Gallagher, M. D. Available via Amazon.

It arrived yesterday and I'm already 60 pages into its 247 pages.  A page-turner for sure.  I did, however, refrain from reading any of it in bed last night before drifting off — for obvious reasons.  Experiences of my own incline me to take very seriously "Unseen Warfare."
 
Dr. Gallagher comes across as a very credible witness.  Rooted as he is in Western canons of rationality and scientific method, he nonetheless appreciates that there are points at which methodological naturalism must give way in the teeth of massive evidence of super- and preter-natural phenomena.
 
This article features an interview with Dr. Gallagher.
 
UPDATE (6/14).  I am now up to p. 82.  It gets better and better. Packed with distinctions essential for clear thinking about this topic. 

Intimations of Elsewhere: Sensible Reminders of Hidden Beauty

Salzburg, Austria, December 1971. A young Austrian girl, radiant and beautiful, walked into the kitchen. I lost all desire for the food I had prepared.  My soul sprouted wings. The visible beauty triggered a memory of a timeless Beauty. Anamnesis pierced for a moment the amnesia induced by the bodily senses.

Dayton, Ohio, 1978. Gripped by the audible beauty of the Beethoven Violin Concerto in D major, the solo passage near the beginning of the Larghetto (26:33), upon return from a long, hard run, I could not eat the huge salad I had prepared. I set it down, my appetite gone.

Simone Weil (FLN, 318): "When once the whole of one's desire is turned toward God, one has no desire to eat when one is hungry."

The metaphysical elsewhere: beyond space, before time. Space- and time-bound as we are 'at present,' we must use spatial and temporal language to point beyond the spatiotemporal.

The intimations are rare. Don't ignore them, record them, honor and remember them. To dismiss them as the worldly are wont to do strikes me as the height of spiritual foolishness.

Contemplating Suicide?

Are you quite sure that there is a way out? It may be that there is no exit.  You can of course destroy your body, and that might do the trick. But then again it might not. Or is it perfectly obvious that you are either identical to your body or necessarily dependent for your existence on its existence?  You might want to think about this before making the leap of faith in ultimate nonentity.  

Pike Other SideIt would be fairly easy to give strong arguments why TO BE is not the same as TO BE PHYSICAL. Think of so-called 'abstract objects.' It is much more difficult to argue persuasively that the identity fails in the case of persons. And yet persons are rather remarkable. The ones we are regularly acquainted with are also animals. Sunk in animality as we are, it is easy to think that we are are just highly evolved animals.  It is easy to miss the wonder of personhood. But the abyss that separates man from the animal should give one pause. 

Bishop James A. Pike's son Jim committed suicide. He supposedly communicated the following message to his father from the Other Side:

I thought there was a way out; I wanted out; I've found there is no way out. I wish I had stayed to work out my problems in more familiar surroundings.  (James A. Pike, The Other Side: An Account of My Experiences with Psychic Phenomena, Doubleday, 1968, p. 118.)

 

Pike James A.If you were around in the '60s and hip to what was happening you will recall Bishop Pike. He was a theological liberal who made quite a splash the ripples of which have long since subsided. The book I have cited  is worth reading but best consumed with a mind both open and critical.

Mortalism

According to Peter Heinegg, mortalism is "the belief that the soul – or spark of life, or animating principle, or whatever — dies with the body. . . ." (Mortalism: Readings on the Meaning of Life,  Prometheus, 2003, p. 9). Heinegg was raised Catholic and indeed was a member of the Jesuit order for seven years. In an essay prefatory to his anthology, he explains why he is a mortalist. Suppose we examine some of his statements.

That anyone should be a mortalist does not surprise me, but it does surprise me that anyone should consider it an "obvious fact" that death is the "irrevocable end" of a person. But this is what Heinegg holds: "Everybody knows that the soul dies with the body, but nobody likes to admit it." (11) Priests and metaphysicians may prate about immortality, but deep down in the bowels of the body we all know that we are mortal to the core:

     As surely as the body knows pain or delight, the onset of orgasm or
     vomiting, it knows that it (we) will die and disappear. We have a
     foretaste of this every time we fall asleep or suffer any
     diminution of consciousness from drugs, fatigue, sickness,
     accidents, aging, and so forth. The extrapolation from the fading
     of awareness to its total extinction is (ha) dead certain. (13, emphasis added)

This is as close as Heinegg comes to an argument in his personal statement, "Why I am a Mortalist." (11-14) The argument has but one premise:

   1. We experience the increase and diminution of our embodied
   consciousness in a variety of ways.

   Therefore

   2. Consciousness cannot exist disembodied.

But surely (2) does not follow from (1). If (2) followed from (1), then it would be impossible for (1) to be true and (2) false. But it is easy to conceive of (1) being true and (2) false. It might be like  this: as long as the soul is attached to the body, its experiences are deeply affected by bodily states, but after death the soul continues  to exist and have some experiences albeit experiences of a different sort than it had while embodied.  Variations in the quality of consciousness would be exactly what one would expect given the soul's embodiment.

Consider near-death experiences. A man has a massive heart attack and has a profoundly blissful experience of a white light at the end of a tunnel. Would any committed mortalist take such an experience as proving that there is life after bodily death? Of course not. The mortalist would point out that the man was not fully dead, and would use this fact to argue that the experience was not veridical. The mortalist  would point out that no conclusions about what happens after death can be drawn from experiences one has while still alive. By the same token, however, a consistent mortalist should realize that this same principle applies to his experiences of the waxing and waning of his consciousness: he cannot validily infer from these experiences that consciousness cannot exist disembodied.  For his experiences of the augmentation and diminution of of consciousness are enjoyed while the person's body is alive.

What puzzles me about Heinegg is not that he is a mortalist, but that he is so cocksure about it.  One can of course extrapolate from the fading of consciousness to its total extinction, and not unreasonably; but that the extrapolation is "dead certain" is simply a leap of faith — or unfaith.

Related post: Near-Death Experiences:  Do They Prove Anything?

Can the Existence of God be Proven?

A reader inquires,

I was wondering whether you had any direction you could offer for rational arguments for God's existence?

If you are looking for arguments that are not merely rational, but rationally compelling, I don't believe that there are any.  I also believe that there aren't any such arguments for the nonexistence of God.  A rationally compelling argument for a proposition is a proof; a rationally compelling argument for its logical contradictory is a disproof.  When it comes to God, and not just God, there are no proofs or disproofs. There are arguments, some better than others. That's as good as it gets.

Note that my claim that this is so is not a proposition that I claim to be able to prove.  I claim merely that it is reasonable to believe.  I do believe it and will continue to believe until someone gives me a compelling reason not to believe it. If I am right, however,  that cannot happen. For my meta-philosophical thesis is substantive, and if I am right, said thesis can neither be proven nor disproven. So the the best you could do would be counter me with the contradictory of my meta-thesis. But then we would be in a stand-off.

What is it for an argument to be rationally compelling?

Philosophers make reasoned cases for all manner of propositions, but their colleagues typically do not find these arguments to be compelling.  So a reasoned case need not be a compelling case.  But it depends on what exactly is meant by 'compelling.'  I suggest that a (rationally) compelling argument is one which forces the 'consumer' of the argument to accept the argument's conclusion on pain of being irrational.  (What is it to be irrational? That's a long story I cannot now go into, but the worst form of irrationality would be the acceptance of a logical contradiction.) I will assume that the 'consumer' is intelligent, sincere, open to having his mind changed, and well-versed in the subject matter of the argument.  Now it may be that there are a few arguments that are rationally compelling in this sense, but there are precious few, and surely no arguments for or against the existence of God.
 
To appreciate this, note first that arguments have premises and that no argument can prove its own premises. (An argument of the form p therefore p is an argument valid in point of logical form in which premise and conclusion are identical, but no one will take an argument of this form as proving that p.)  Now given that no argument can prove its own premises, what reason could one give for accepting the premises of a given argument?  Suppose  deductive argument A has P1 and P2 as premises and that conclusion C follows logically from the premises.  Why accept P1 and P2?  One could adduce further arguments B and C for P1 and P2 respectively.  But then the problem arises all over again.  For arguments B and C themselves have premises.  If P3 is a premise of B, what reason could one give for the acceptance of P3? One could adduce argument D.  But D too has premises, and if you think this through you soon realize that you have brought down upon your head an infinite regress which is vicious.  The regress is vicious because the task of justifying by argument all the premises involved cannot be completed.
 
To avoid argumentative regress we need premises that are self-justifying in the sense that they are justified, but not justified by anything external to themselves.  Such propositions could be said to be self-evident.  But what is self-evident to one person is often not self-evident to another.  This plain fact forces a distinction between subjective and objective self-evidence.  Clearly, subjective self-evidence is not good enough.  If it merely seems to subject S that p is self-evident, that does not suffice to establish that p is objectively self-evident.  Trouble is, when someone announces that such-and-such is objectively self-evident that too is a claim about how it seems to that person, so that it is not clear that what is being claimed as objectively self-evident is not in the end itself merely subjectively self-evident.
 
Example.  Suppose an argument for the existence of God employs the premise, 'Every event has a cause.'  Is this premise self-evident?  No.  Why can't there be an uncaused event?  So how does one know that that premise is true?  It is a plausible premise, no doubt, but plausibility is not the same as truth.  And if you do not know that the premises of your argument are true, then your argument, even if logically impeccable in every other way, does not amount to a proof, strictly speaking.  Knowledge entails certainty, objective certainty.
 
My point is that there are hardly any rationally compelling arguments for substantive theses.  But one can make reasoned cases for theses.  Therefore, a reasoned case is not the same as a compelling argument.
 
Because people are naturally dogmatic and crave doxastic security, they are unwilling to accept my meta-philosophical thesis that there are hardly any compelling arguments for substantive theses.  They want to believe that their pet beliefs are compellingly provable and that people who do not accept their 'proofs' are either irrational or morally defective.  Their tendency is to accept as sound any old argument for the conclusions they antecedently accept, no matter how shoddy the argument,  and to reject as unsound arguments that issue in conclusions they do not accept.  Their craving for doxastic security swamps and suborns their critical faculties.
 
One way to refute what I am saying would be by providing a compelling argument for the existence of God, or a compelling argument for the nonexistence of God.  You won't be able to do it. 

In the absence of compelling arguments, what should one do?

I don't believe that there can be talk of proof when it comes to God, the soul, and other big topics, assuming you use 'proof' strictly.  After considering all the evidence for and against, you will have to decide what you will believe and how you will live.  The will comes into it. One freedom comes into it. I thus espouse a limited doxastic voluntarism. In the shadowlands of this life there is light enough and darkness enough to lend support to either answer, that of the theist and that of his opposite number.  So it is up to you to decide what you will believe and how you will live.

For me the following consideration clinches the matter.  Bring the theoretical question back down to your lived life, your Existenz in the existentialist sense.  How will you live, starting right now and for the rest of your days?  Will you live as if you will be utterly extinguished in a few years or will you live as if what you do and leave undone right now matters, really matters? Will you live as if life is serious, or will you live as if it is some sort of cosmic joke?  Will you live as if something is at stake in this life, however dimly descried, or will you live as if nothing is ultimately at stake?  Will you live life as if it has an Absolute Meaning that transcends the petty particular relative meanings of the quotidian round?  Will you take the norms that conscience reveals as so many pointers to an Unseen Order to which this paltry and transient sublunary order is but prelude?

It is your life.  You decide.  You can drift and not decide, but your drifting in the currents of social suggestion and according to the idols of the age is a deficient  mode of decision. Not to decide is to decide.

Now suppose that when Drs. Mary Neal and Eben Alexander die the body's death, they become nothing.  Suppose that their phenomenologically vivid paranormal after-death experiences were revelatory of nothing real, that their experiences were just the imaginings of malfunctioning brains at the outer limits of biological life.  What will they have lost by believing as they did?

Nothing! Nothing at all.  You could of course say that they were wrong and were living in illusion and giving themselves and others false hope.  But no one will ever know one way or the other.  And if the body's death is the last word, then nothing ultimately matters, and so it can't matter that they were wrong if turns out that they were.

If they were right, however, then the moral transformation that their taking seriously of their experiences has wrought in them can be expected to redound to their benefit when they pass from this sphere. 

Mary Neal’s Out-of-Body Experiences: Do They Prove Anything?

A repost from 16 December 2012 with minor edits.

………………………………………..

The personable Dr. Neal recounts her experiences during this 13 and a half minute video clip.  The following from an interview with her:

The easy explanations—dreams or hallucinations—I could discount quickly, because my experience—and the experience described by anyone who's had a near death experience or other experiences that involve God directly—is different in quality and memory from a dream or hallucination. It's just entirely different. The memory is as precise and accurate now, years later, as it is when it's happening.

So then I thought it must be due to chemical changes or chemical releases in a dying brain. I did a lot of reading about that. If my experience had lasted five, six, seven minutes, maybe even eight minutes, I am sure that no matter how real it seemed to me, I would have said that's a reasonable explanation. But the people who resuscitated me would say that I was without oxygen for up to thirty minutes.

It took them ten or fifteen minutes to figure out, first, that I and my boat were both missing. Then once they identified where they thought I was, they started their watch. They're used to doing this—you have to know the timing so you can recognize whether you're trying to rescue someone or you're trying to go for body recovery. So on the watch it was fifteen minutes, but about thirty minutes in all. I tend to stick with the fifteen minutes, because that's an absolute timing. But even at fifteen minutes, that is way longer than can be explained by a dying brain. The human brain can hang on to oxygen for maybe five or six minutes, and so even if you give it another four minutes to go through its dying process, that still doesn't add up to fifteen minutes. And so after I looked at all that, my conclusion was that my experience was real and absolute.

To paraphrase Blaise Pascal, there is light enough for those who want to see and darkness enough for those who don't.  Atheists and mortalists will of course not be convinced by Neal's report.  Consider her first paragraph.  She underscores the unique phenomenological quality of OBEs.  Granting that they are phenomenologically different from dreams and ordinary memories, there is nonetheless a logical gap between the undeniable reality of the experiencing and the reality of its intentional object.  Into that gap the skeptic will insert his wedge, and with justification.  No experience, no matter how intense or unusual or protracted, conclusively proves the veridicality of its intentional object. 

Phenomenology alone won't get you to metaphysics.  Everything I am perceiving right now, computer, cup, cat, the Superstition ridgeline and the clouds floating above it (logically) might have a merely intentional existence.  How do I know I am not brain in a vat?  If I cannot prove that I am not a brain in a vat, how can I know (in that tough sense in which knowledge entails objective certainty)  that cat, cup, etc. are extramentally real?  The skeptic can always go hyperbolic on you. How are you going to stop him?

The other consideration Dr. Neal adduces will also leave the skeptic cold.  Her point is that her brain had to have been 'off-line' given the amount of time that elapsed, and that therefore her experiences could not be the product of a (mal)functioning brain.  We saw in an earlier post  that Dr. Eben Alexander employed similar reasoning.  The skeptic will undoubtedly now give a little a speech about how much more there is yet to know about the brain and that Neal is in no position confidently to assert what she asserts, etc.

The mortalist starts and ends with an assumption that he cannot give up while remaining a mortalist, namely, that there just cannot be mental functioning without underlying brain activity, and that therefore no OBEs can be credited if they are interpreted in a manner to support the claim that consciousness can exist without a physical substratum. How does the mortalist/materialist know this?  He doesn't. It's a framework assumption. He certainly doesn't know it from any natural-scientific investigation.  It is clear that some brain changes are followed by mental changes. That shows that embodied consciousness is dependent on the brain. But it says nothing about consciousness in its disembodied state. 

In the grip of that materialist framework assumption,  the mortalist will do anything to discount the veridicality of OBEs.  Push him to the wall and he will question the moral integrity of the reporters.  "They are just out to exploit human credulousness to turn a buck."  Or they will question the veridicality of the memories of the OBEs.  The human mind can be extremely inventive in cooking up justifications for what it wants to believe.  That is as true of mortalists as it is of anyone.  To paraphrase Pascal again, there is enough darkness and murk in these precincts to allow these skeptical maneuvers.

Our life here below is a chiaroscuro.

There is no proof of the afterlife.  But there is evidence.  Is the evidence sufficient?  Suppose we agree that evidence for p is sufficient just in case it makes it more likely than not that p.  Well, I don't know if paranormal and mystical  experience is sufficient because I don't know how to evaluate likelihood in cases like these.

So let's assume that the evidence is not sufficient.  Would I be flouting any epistemic duties were I to believe on insufficient evidence?  But surely most of what we believe we believe on insufficient evidence.  See Belief and Reason categories for more on this.)

Those who believe that it is wrong, always and everywhere, to believe anything on insufficient evidence believe that very proposition on insufficient evidence, indeed on no evidence at all.