In his recent book Waking Up: A Guide to Spirituality Without Religion (Simon and Schuster, 2014), neuroscientist and philosopher Sam Harris provides some critical comments on near-death experiences (NDEs) as part of his larger exploration of spiritual experiences. Most of his discussion on NDEs involves a critical engagement with neurosurgeon Eben Alexander’s Proof of Heaven: A Neurosurgeon’s Journey into the Afterlife (Simon and Schuster, 2012). In this New York Times best seller, Alexander provides an account of his own near-death experience that occurred after contracting E. coli bacterial meningitis and falling into a weeklong coma. Alexander claims that during his coma he experienced an NDE that provides “extremely strong evidence” that consciousness is independent of the brain and so will survive physical death. Harris contends that Alexander has not succeeded in showing that his experience provides compelling evidence for these claims.
I’ve elsewhere discussed my reservations about arguments that purport to show that NDEs provide good evidence for life after death. The critical evaluation of NDEs as alleged evidence for life after death occupies an important place in my recently published Philosophical Critique of Empirical Arguments for Postmortem Survival (Palgrave Macmillan, 2015). Although my main objections to these arguments are a bit different from Harris’s particular criticisms of Alexander, I’m in agreement with Harris that the conclusions Alexander draws about his experience are simply not good inferences, much less rationally compelling ones.
Harris raises several specific objections to Alexander’s reasoning, but the central objection concerns Alexander’s controversial contention that he had his NDE while his cerebral cortex was completely shutdown and inactive. This is an important premise in Alexander’s argument for supposing that consciousness does not depend on the brain and so can survive death. Harris argues that Alexander has not provided good, much less compelling, reason to accept it. First, Alexander’s reasons for claiming that his cerebral cortex was inactive are inadequate. Second, even if we grant that Alexander’s cortex was inactive during his coma, Alexander’s reasons for claiming that his NDE occurred during the time of cortical inactivity are inadequate. It’s important to emphasize, and I’ll comment on this further below, that Harris does not argue that Alexander’s controversial claim is false. His central contention is that Alexander has not provided good enough reason to suppose that this premise is true.
It probably won’t come as a surprise that I agree with Harris. Equally unsurprising, Eben Alexander strongly disagrees with Harris and my positive evaluation of Harris’s criticisms. A couple of months ago I voiced my agreement with Harris’s critique of Alexander in a Facebook post, which prompted a response from Alexander (whom I had tagged in the post). Alexander was quite emphatic that Harris “makes no good points at all,” and he cited Bernardo Kastrup as having provided a “reasonable response to his [Harris’s] rantings.” In my correspondence with Alexander over the past two months, he strikes me as a sincere person who had a genuinely transformative experience, and his endgame—awakening people to the spiritual dimension of life—is one Harris and I actually share with Alexander. However, like Harris, I’m skeptical of how spiritual experiences, including NDEs, are used to prop up grandiose metaphysical claims.
In the present blog, I examine Bernardo Kastrup’s criticisms of Harris’s critique of Alexander. Although in a future blog I intend to provide some of my own criticisms of Alexander’s interpretation of his NDE, here I aim only to defend Harris’s critique. It’s astonishingly evident to me that Kastrup’s thinking on this matter is not merely confused; it’s profoundly confused. It’s not just that Kastrup’s punches fail to land. Harris is not even in the ring. Kastrup is engaged in little more than an elaborate exhibition of shadowboxing. Why? Kastrup simply doesn’t understand Harris’s critique. Naturally he falls victim to a whole series of misguided, fallacious counter arguments. It’s actually difficult to assess who has done more damage to Alexander’s NDE argument for an afterlife, Harris or Kastrup.
One disclaimer of sorts: this is a lengthy blog. However, given the popularity of NDE arguments for life after after death and the bad rap Sam Harris has received on this issue from a wide range of critics (who essentially reproduce the inadequacies of Kastrup’s critique), a detailed and thorough response was warranted.
1. Sam Harris vs. Bernardo Kastrup
Harris originally discussed Eben Alexander’s NDE in his blog “This Must be Heaven” (October 2012), which was a response to the October 8, 2012 Newsweek article on Eben Alexander. Harris followed up with a second blog “Science on the Brink of Death” (November 2012). His discussion in his recent Waking Up is culled from these earlier blogs. I’d say it’s highly inaccurate, actually quite bizarre, to describe either of these discussions as a rant. To be sure, Harris is straightforward, and his criticisms can be hard hitting, but he’s typically fair, despite what emotionally immature religious critics would have us believe. Harris’s position on NDEs in particular is considerably more modest than the impression left by either Alexander or Kastrup. But hard-hitting criticism, even when presented with moderation and fairness, will doubtlessly sound like a rant to those who are deeply attached to extraordinary claims. And when a highly educated neurosurgeon and best-selling author running as a GOP presidential hopeful—I refer to Dr. Ben Carson—can sincerely claim that the theory of evolution originated from Satan, we clearly live in a world in which even educated neurosurgeons are not exempt from propagating extraordinary claims rooted in the fear-based metaphysics of the dark ages. The expectation that such claims should be countered by criticisms wrapped in antiseptic niceties would be unreasonable.
Kastrup’s critique of Harris appears in chapter 6 of his book Brief Peeks Beyond: Critical Essays on Metaphysics, Neuroscience, Free Will, Skepticism, and Culture (Iff Books, 2015), but the material on Harris originally appeared in Kastrup’s blog in fall 2012, first as “Sam Harris’ Critique of Eben Alexander” (October 13, 2012), and subsequently in the emotionally charged “Sam Harris Proud and Prejudiced” (November 13, 2012). These were Kastrup’s responses to Harris’s blog from the same months. Since books with forwards by Deepak Chopra land somewhere near the bottom of my reading list, it’s doubtful that Kastrup would have come on my radar had Alexander not referenced him. Alas, after reading Kastrup, books with forwards by Deepak Chopra will henceforth land at the bottom of my reading list. Kastrup’s reasoning in both his blog and book is an astonishing display of misrepresentation and philosophical obfuscation.
In the interest of accessibility for readers, in what follows I’ll primarily quote from the blog versions of the respective material, with occasional references to book material. Neither Harris nor Kastrup altered the substance of their arguments in their subsequent book publications. Unless otherwise noted, all quotes are from Harris’s “This Must be Heaven” and Kastrup’s “Sam Harris’ Critique of Eben Alexander.”
2. Kastrup’s Confusion
In his blog “Sam Harris’ Critique of Eben Alexander,” Bernardo Kastrup begins by stating his intuition that Alexander’s NDE story is “authentic.” As the immediate context and subsequent discussion make clear, Kastrup means to say that he’s inclined to accept Alexander’s claim that his consciousness really left his body or that it is/was otherwise independent of Alexander’s brain. As Alexander himself said, “I was encountering the reality of a world of consciousness completely free of the limitations of my physical brain” (Proof of Heaven, 9). Since this view is typically designated the “extrasomatic” interpretation of NDEs, I’ll henceforth refer to it as such. Like others, Alexander infers from the extrasomatic interpretation of his NDE that “the death of the body and the brain are not the end of consciousness, that human experience continues beyond the grave” (Proof of Heaven, 9). Kastrup says that Alexander’s account fits his own model of what will happen to consciousness after the cessation of brain activity. Kastrup then introduces Sam Harris as a well-known “atheist activist” who “seems to disagree.”
It’s somewhat baffling that, in an article devoted to the project of dismantling the atheist activist’s critique of Alexander, no effort is made to actually state Harris’s argument, either at the outset or at any subsequent point. But the knot of confusion has already been tightly tied because Harris is described as seeming to disagree, not with how Alexander reaches his conclusions—the extrasomatic interpretation of his NDE and the related afterlife claim—but with these conclusions themselves. It’s thereby at least insinuated that Harris denies the authenticity of Alexander’s NDE. This profound interpretive error vitiates Kastrup’s entire critique in both articles (and in his book), and it sadly inspires Kastrup’s creation of less than imaginative arguments that he incorrectly attributes to Harris.
Without a clue as to what Harris argues, Kastrup immediately launches his critique of Harris. The critique revolves around the accusation of unjustified assumptions on Harris’s part. “I believe,” says Kastrup, “there to be a couple of faulty assumptions and unfair, implicit suggestions in Harris’ critique.” Now arguments are indeed vulnerable to defeat if they make unjustified assumptions, so the general strategy is sound, but Kastrup’s execution is utterly unsound. To know whether Harris actually makes the assumptions Kastrup is about to attribute to him, we would need to know what Harris actually argued, and Kastrup would then need to show why Harris’s argument requires these assumptions. Kastrup hasn’t provided this important information. This is either an unscholarly goof or a deliberate attempt to misguide the reader. And it’s all down hill from here.
3. NDEs and Drug-Induced Experiences
The first of Harris’s alleged assumptions is extrapolated from a Harris quote (lifted from Harris’s “This Must be Heaven” blog), in which Harris provides evidence for there being significant similarities between Alexander’s NDE and experiences induced by anesthetics such as ketamine or, more significantly, psychedelics such as N,N-Dimethyltryptamine (commonly referred to as DMT). Harris had said that Alexander’s “experience sounds so much like a DMT trip that we are not only in the right ballpark, we are talking about the stitching on the same ball” (cf. Waking Up, 180). From this brief single quote, for which no context is given, Kastrup extrapolates the following:
Here the implicit suggestion is that, because of similarities between a psychedelic experience (DMT is an endogenous psychedelic) and Alexander’s NDE, the latter was likely generated by brain chemistry and, therefore, had no reality to it. Underlying this suggestion is the completely unsubstantiated notion, or assumption, that no valid transcendent experience can be initiated by physical means like alterations of brain chemistry.
Harris is here explicitly depicted as appealing to the similarity between DMT experiences and Alexander’s NDE in order to show that it’s likely that Alexander’s experience was not real. Let’s unpack this a bit. The chain of reasoning attributed to Harris runs like this: (1) Alexander’s NDE is sufficiently similar to experiences that are produced by brain chemistry, so it’s likely that (2) Alexander’s NDE was produced by brain chemistry. Since (3) no valid transcendent experience can be initiated by physical brain-based processes, it’s therefore likely that (4) Alexander’s NDE was not a valid transcendent experience, where (4) entails the denial of the extrasomatic interpretation of Alexander’s NDE.
Among these four claims attributed to Harris, only (1) can plausibly be attributed to him. Harris nowhere claims (2), much less on the basis of (1). Furthermore, note that Kastrup re-describes Alexander’s NDE as a “valid transcendent experience,” but this is as question begging as it is misleading. As many Advaitin Vedantins and Buddhists would inform Kastrup, “valid transcendent experience” need not entail that consciousness, especially individual consciousness, can exist independent of the body. Why must a valid transcendental experience require that we deny that the brain produces particular mental states or that states of consciousness are otherwise dependent on a functioning brain? But even if we adopt the question begging re-description of Alexander’s experience, Harris nowhere claims (3) or (4), much less (4) on the basis of (3). Harris nowhere denies the extrasomatic interpretation of Alexander’s experience. Kastrup has created, for the purposes of a clearly premeditated refutation, an entire argument that Harris never actually presented.
If we pay any attention to what Harris actually argued in his blog (and later in Waking Up), at no point did he claim that Alexander’s NDE was not authentic. Harris didn’t argue that it’s likely that Alexander’s experience was a delusion or hallucination, nor does he claim that it didn’t involve the separation of Alexander’s consciousness from his body. As Harris makes clear, though there are good reasons to suppose that consciousness is an emergent property of the brain, he remains agnostic about the relationship between consciousness and the physical world. Therefore, he is in principle open to the kind of interpretation Alexander gives to his experience (cf. Waking Up, 175-6, End of Faith, 208). What Harris argues is that Alexander has not provided compelling evidence to suppose that his experience was authentic.
But Alexander’s account is so bad—his reasoning so lazy and tendentious—that it would be beneath notice if not for the fact that it currently disgraces the cover of a major newsmagazine. . . .Again, there is nothing to be said against Alexander’s experience. It sounds perfectly sublime. And such ecstasies do tell us something about how good a human mind can feel. The problem is that the conclusions Alexander has drawn from his experience—he continually reminds us, as a scientist — are based on some very obvious errors in reasoning and gaps in his understanding. (“This Must be Heaven,” cf. Waking Up: 185)
It’s one thing to argue, as some do, that we have compelling evidence that Alexander’s experience could not be genuine, for instance because there are considerations from the philosophy of mind or cognitive neuroscience that allegedly provide overriding evidence that consciousness is reducible to or causally dependent on brain functioning. It’s quite another to argue — as Harris does — that Alexander has not provided compelling evidence to suppose that his experience was authentic. This is no minor philosophical quibble. In the first instance, we have the burden of showing that the conclusion of an argument is false. In the second instance, we only have the burden of showing that a purported argument in support of a conclusion fails to provide good reason to accept the conclusion. Having a good reason to believe that a claim is false is not the same as lacking a good reason to believe that a claim is true. While one might have other grounds for accepting the conclusion in the latter case, Harris’s position, as he makes clear, is the moderate position of the agnostic who is open to a possibility that Alexander has simply failed to show to be true.
With this in mind, we can perhaps appreciate, as Kastrup does not, why Harris has introduced the alleged resemblance between Alexander’s NDE and drug-based experiences, especially DMT experiences. To see this and how Kastrup misses it, consider first how Kastrup spins it:
So Harris’ assumption that a physical trigger cannot lead to a perfectly valid NDE seems to completely miss the point in contention. After all, most NDEs are initiated by physical events anyway. Yes, Alexander’s NDE bears similarities with psychedelic trances, at least as far as descriptions go. But psychedelic experiences can, and probably are, entirely valid transcendent experiences not generated by the brain, as the latest research suggests. The comparison does not at all defeat the validity of Alexander’s NDE.
Kastrup is here again creating an argument and attributing it to Harris, but Harris never made the argument. Apart from the resemblance thesis, Harris never made the claims attributed to him here. He does not assume, for instance, that a physical trigger cannot lead to a perfectly valid NDE. Kastrup is correct, of course, that in at least one sense the similarity between Alexander’s NDE and DMT experiences doesn’t defeat the authenticity of the former as a valid transcendent experience, even under the extrasomatic interpretation of the latter. The two claims are logically compatible, so one is not evidence against the latter.
However, Kastrup’s reasoning is a red herring, stemming from his misconstruing the dialectical structure of Harris’s critique. Kastrup thereby misses how the resemblance thesis does defeat Alexander’s argument. As Harris shows, Alexander claims — in defense of the validity of his NDE — that his experience was not like drug-induced experiences, “not even in the right ballpark” to use Alexander’s phrase. As Harris explains, “Alexander believes that his E. coli-addled brain could not have produced his visions because they were too ‘intense,’ too ‘hyper-real,’ too ‘beautiful,’ too ‘interactive,’ and too drenched in significance for even a healthy brain to conjure.” Harris draws on Terence McKenna’s account of DMT trips to show how the qualities Alexander attributes to his experience are prominent features of DMT trips.
To anticipate a likely response at this point, yes — having read Proof of Heaven — I’m aware that Alexander acknowledges that he’s had experiences on LSD and mescaline, and that he’s observed patients on DMT (Proof of Heaven, 186). But there’s nothing Alexander says about these experiences that contradicts what Harris says about the resemblance between Alexander’s description of his NDE and how others have described their experiences on DMT. Harris’s claim is compatible with Alexander knowing, on the basis of his own LSD trips, that his NDE was nothing like his experiences on LSD. And there’s nothing that Alexander could have observed in the behavior of patients on DMT that contradicts the general phenomenology of such experiences.
The central point: it’s not that Harris is inferring the improbability of the authenticity of Alexander’s experience from its resemblance to drug-induced experiences. It’s that Alexander’s argument in defense of the authenticity of his experience relies on denying this resemblance. Harris is simply rebutting this denial. It’s Alexander who has made the dialectically unwise maneuver of making his own argument depend on a premise whose falsehood even Kastrup is willing to acknowledge.
4. Alexander’s “Cortical Inactivity” Claim
As Harris repeated in “Science on the Brink of Death,” the central weakness in Alexander’s argument is that “there is absolutely no reason to believe that his cerebral cortex was inactive at the time he had his experience of the afterlife” (cf. Waking Up, 178). Let’s be as clear as possible. The conclusion Alexander wishes to reach about the extrasomatic nature of his experience rests on his being justified in two claims: (i) there was a period of time during which Alexander’s cerebral cortex was completely inactive and (ii) Alexander had his NDE during this time. Harris does not argue that either (i) or (ii) is false. He argues that Alexander has not provided good or compelling evidence that both are true. Kastrup has simply not understood the structure of Harris’s argument, in part because he’s apparently not understood what Alexander must argue for his own conclusion.
With respect to (i), Harris writes:
Everything—absolutely everything—in Alexander’s account rests on repeated assertions that his visions of heaven occurred while his cerebral cortex was “shut down,” “inactivated,” “completely shut down,” “totally offline,” and “stunned to complete inactivity.” The evidence he provides for this claim is not only inadequate—it suggests that he doesn’t know anything about the relevant brain science . . . . The problem, however, is that “CT scans and neurological examinations” can’t determine neuronal inactivity—in the cortex or anywhere else. And Alexander makes no reference to functional data that might have been acquired by fMRI, PET, or EEG—nor does he seem to realize that only this sort of evidence could support his case. . . .Coma is not associated with the complete cessation of cortical activity, in any case. And to my knowledge, almost no one thinks that consciousness is purely a matter of cortical activity. (cf. Waking Up, 177-8)
Kastrup’s response to this is as follows:
Much of Harris criticism rests on an old materialist argument against NDEs: It cannot be shown that all of Alexander’s brain functions were off, so it is conceivable that there was enough brain function left to confabulate an unfathomable dream. This is as promissory as it is unfalsifiable, for there might indeed always be a neuron firing somewhere. But that’s not the point, is it? The point is whether the kind of brain function that ordinarily always correlates to the experience of complex dreams can be realistically expected to have been present in Alexander’s case. If chaotic, impaired, residual cortical function could explain the confabulation of a complex and coherent trip to “heaven,” then such residual cortical function would probably suffice ordinarily too, wouldn’t it?
And to claim that a bacteria-infested neocortex, at the level verified in Alexander’s case, retains enough coherent function to do this seems to stretch credulity under the materialist notion that experience is coherent brain activity. To dismiss Alexander’s experience on the basis of warped speculation about residual neocortical function amounts to dismissing extremely interesting, anomalous data. Something extraordinary has happened, and true skeptics should take a critical look at it while retaining a healthy dose of skepticism towards the standard explanations too; that’s how science historically has moved forward.
Once again, Kastrup has misrepresented the structure of Harris’s argument. Harris is not dismissing Alexander’s experience because Harris thinks Alexander had or could have had sufficient cortical activity (or sufficient activity elsewhere in his brain) to underwrite the experience. Harris is not proposing any alternative materialistic explanation of Alexander’s experience. As should be apparent from the quoted material above, Harris is simply questioning whether Alexander has provided sufficient evidence for the claims Alexander makes about the functionality of his cortex at the time of his experience. And contrary to what Kastrup says, Harris does not claim that Alexander cannot show that his brain was offline. Harris implies just the very opposite. Alexander could indeed show this, by providing data on the functionality of his brain during the time period in question.
As explicitly stated in the above quotes, Harris is quite specific as to why Alexander’s evidence for cessation of cortical activity is weak and thus far from carrying the degree of warrant that would be required to draw the conclusion that his experience provides “extremely strong evidence” for consciousness being independent of the brain or “proof” of an afterlife. Since the point here is central, here’s how Harris summed it up in Waking Up.
Unfortunately, the evidence that Alexander offers—in the [Newsweek] article, in a subsequent response to my public criticism of it, in his book, and in multiple interviews—suggests that he doesn’t understand what would constitute compelling evidence for his central claim of cortical inactivity. The proof he offers is either fallacious (CT scans do not measure brain activity) or irrelevant (it does not matter, even slightly, that his form of meningitis was “astronomically rare”)—and no combination of fallacy and irrelevancy adds up to sound science. Alexander makes no reference to functional data that might have been acquired by fMRI, PET, or EEG—nor does he seem to realize that this is the sort of evidence necessary to support his case. (Waking Up, 177-8)
The reasoning here is as straightforward as it gets. If CT scans and neurological examinations don’t provide the right kind of information to make reliable determinations about neuronal inactivity, it’s insufficient for Alexander to rely on such exams to draw conclusions about cortical activity. If functional exams provide the required information and Alexander doesn’t have this information, then his contention that his cortex was offline is at best a fairly weak conjecture about his experience. Full stop. And observe that Harris isn’t making a novel argument here. It’s echoed by a choir of other commentators (who are either neuroscientists or neurologists), including Oliver Sacks, Steven Novella, Ernst Rodin, Stanley Goldin, and even Harris’s former Ph.D advisor at UCLA, Dr. Mark Cohen, a specialist in neuroimaging.
Alexander has repeatedly refused to respond to the kind of challenge Harris presents. For example, in the debate Death is not Final (featuring Alexander and Raymond Moody up against Steven Novella and Sean Carroll), Novella raised this direct challenge to Alexander.
When you were at your worst, there wasn’t the kind of functional monitoring that we would have needed to know that your brain was not functioning at all. We don’t know that. We saw anatomically we had edema and swelling, and that certainly would have kept you unconscious, but you weren’t getting an fMRI, PET scan, or any EEG as far as I can see, in anything you’ve written or said about it, that would have documented zero brain activity. You can’t say that. Nobody can say that. (@52:00, Death is not Final).
Alexander was able to evade answering Novella’s challenge in this debate because the moderator quickly changed the topic—deus ex machina. Kastrup evades the challenge with no similar moment of dialectical redemption. To refute Harris, Kastrup would need to show one of two things: either Harris is mistaken about what CT scans and neurological examinations show about cortical activity, or Alexander has other data that make it highly improbable that his cortex was functional at any time during his coma. Kastrup does neither. Instead, he merely plays hide the ball by deploying question-begging language that illicitly shifts the burden of proof. He merely assumes that, given the facts, it’s improbable that Alexander’s cortex could have produced the experiences he reports. An argument needs to be made for this, but none is given.
So I think we can concede that Kastrup is at least correct to say that whether there could have been residual brain activity misses the point. Yes, this does miss the point. But the point is not, as Kastrup supposes, that skeptics lack compelling evidence to suppose that Alexander’s cortex was capable of producing the experience. The point is that Kastrup has not shown that the known facts make it probable that Alexander’s cortex was incapable of producing the experience.
5. Failures of Proper Argumentation
Here it’s worth emphasizing that Alexander’s original account in Proof of Heaven does no better at establishing his cortical inactivity than Kastrup does in defending this claim against Harris’s criticisms. Alexander claims that his cortex was non-functional or inactive, but his evidence for this is utterly inadequate. As Harris argued, merely citing data from CT brain scans and neurological exams, which indicate the severity of his meningitis and associated symptoms (including damage to his cortex), does not give us the kind of data that would be required for strongly supported conclusions about the extent of cortical activity over the weeklong period of Alexander’s coma.
But let me reinforce Harris’s points with further detail. Consider two specific examples of why Alexander’s reasoning is as defective as Harris claims.
(i) Alexander cites various facts that allegedly show “severe alterations in cortical function and dysfunction of extraocular motility, indicative of brainstem damage” (Proof of Heaven, 187). Even if we grant the implicit evidential claim here (note that he does not argue in support of it), it hardly follows that his cortex was completely inactive, or even so impaired that it was incapable of producing the experience in question. While terms like “damage” (which Alexander frequently uses) are imprecise, as anyone who has owned a car, stereo system, or bodily appendage understands, what is damaged is not necessarily non-functional or inactive.
(ii) Alexander repeatedly claims that the facts make it improbable or unlikely that his cortex was functioning, but no argument is given to back up this contentious claim. For example, “Given the prolonged course of my poor neurological function (seven days) and the severity of my infection, it is unlikely that even deeper layers of the cortex were still functioning” (Proof of Heaven, 187-8). Apart from the use of imprecise terms like “poor” (neurological function) and “severity” (of his infection), where is the empirical support for the probability claim here? Does Alexander have statistical information or other data from neuroscience to support this claim?
The point that needs to be underscored here is the utter lack of proper argumentation. Yes, Alexander cites a string of medical facts (of a general nature and concerning his own case), but a set of facts does not a conclusion make. Yes, Alexander states a conclusion, but tacking on a conclusion to a set of facts does not an argument make. If his conclusion is warranted, Alexander should be able to show this by a clear inductive argument. For example, he could develop an argument using statistical data (based on other documented cases) that at least establishes a positive correlation between the medical facts of his case and results from functional exams (in other cases), or he could make an appeal to data drawn from experimental research in neuroscience. Neither Alexander nor Kastrup gives us what the doctor ordered. We’re left with a conjecture the actual probability of which is at best inscrutable.
One clear obstacle to Alexander making the required kind of argument is the uniqueness of his case—repeatedly affirmed by Alexander (Proof of Heaven, 20, 25, 89, 149, 183). This would make it difficult even to construct a good analogical argument, in which he reasoned from known cases of coma-inducing meningitis with available EEG data, where the data indicate precisely what Alexander wishes to say about cortical inactivity in his own case. He presents no such data, and I doubt the data are forthcoming anytime soon. After all, Alexander admits there are very few people who have been in his condition and lived to tell about it, either because they remained in a vegetative state or simply died (Proof of Heaven, 21). Moreover, Alexander can’t sensibly reason to his brain lacking cortical activity from the mere fact that he was in a coma, for as Harris points out “neuroimaging studies show that comatose patients (like patients under general anesthesia) have 50 to 70 percent of the normal level of cortical activity” (Waking Up, 178). So perhaps we should conclude that Alexander fails to make the kind of argument he needs to make because the shallow reserve of empirical facts at his disposal just precludes doing so. But then the appropriate response should be agnosticism.
Let me return to a passage from Kastrup, as it underscores how the lack of proper argumentation vitiates Kastrup’s critique of Harris on the matter of cortical activity.
Studies on the neuronal correlates of consciousness . . . have shown that neocortical activity correlates with the kind of experiences described by Alexander. Thus, to claim rather speculatively that such experiences could happen with a highly malfunctioning neocortex seems to entail a rather biased and contradictory interpretation of the evidence and to raise a deeper question: If Alexander could confabulate that kind of sharp, coherent, complex, ultra-realistic dream with a severely debilitated neocortex, what the heck do we need a healthy neocortex for? Even when we dream of something as trivial as the clenching of a hand, we see clear correlations with neocortical activity; so how come we can supposedly confabulate entire alternative realities, rich in landscapes, entities, and significance, with a highly impaired neocortex? Materialism cannot have it both ways, . . . either you need the brain or you don’t.
First, there’s more begging of the question. Kastrup describes the condition of Alexander’s cortex as “highly debilitated” and “highly impaired.” If these general descriptions are to do the requisite logical work, they must entail or make probable the more specific claim that Alexander’s cerebral cortex was not capable of causally contributing to the kind of experience he reported. This returns us to the point noted above, the insufficiency of Alexander’s account to permit a sufficient or even adequate determination of the level of impairment of his cortex, except by way of an extraordinary leap in logic.
Second, Kastrup’s reasoning is confused for another reason. If neuronal correlates of consciousness have shown that neocortical activity correlates with the kind of experience described by Alexander, we have at least prima facie evidence Alexander had his experience at a time when his neocortex was sufficiently active. (By parity of reasoning, if there’s a positive correlation between being a southerner and liking country music, then Jack’s living in Kentucky is prima facie evidence for supposing that he likes country music.) Functional data showing otherwise might defeat this evidence for cortical activity, which is another reason why the absence of such evidence in Alexander’s case undermines the kind of argument he tries to make. So it’s not just that Alexander’s evidence fails to make it probable that his cerebral cortex was shutdown for the duration of his coma. One could reasonably argue that his data do not defeat the prima facie evidence for cortical activity provided by our background knowledge that his kind of experience correlates with cortical activity.
Finally, even if Alexander had the required functional data, and it provided evidence for cortical shutdown, all that would follow is that the working model for how his brain produces experiences of the sort he reported needs to be revised, but – and this is crucial – this does not require denying that the brain produces consciousness, especially since there’s no fully developed and established view about how the brain produces consciousness in the first place. Or, to put the matter more modestly, if functional data showed cortical shutdown, we would be left with a choice between (a) revising a working though tentative neuroscientific model of how certain parts of the brain produce certain kinds of experience and (b) rejecting the dependency of mental states on brain functioning. Alexander has not provided any reasons to prefer (b) over (a). For there to be good evidence for the extrasomatic interpretation of Alexander’s NDE, we would need more than good evidence for supposing that alternative naturalistic explanations of his experience fail. In other words, we would need the kind of argument that no empirical survivalist has produced to date. In the light of this vast lacuna in explanatory reasoning on the part of survivalists, Harris’s agnosticism is entirely reasonable.
6. Determining the Time of Alexander’s NDE
As indicated above, Alexander’s extrasomatic interpretation of his NDE depends on both the contention that his cerebral cortex was shutdown during his coma and that he had his NDE at some point during the period of cortical inactivity. So Harris correctly argues that even if Alexander could provide good reasons to believe that his cortex completely shut down during his coma, he would also need to provide good reasons for supposing that he had his NDE at that time. Harris denies that Alexander has provided such evidence. Again, as with his earlier claim, Harris doesn’t deny that Alexander’s NDE occurred while his cortex was offline. Harris argues that Alexander was not/is not in the epistemic situation to accurately access when his experience took place: “Even if his entire cortex had truly shut down (again, an incredible claim),” Harris asks, “how can he know that his visions didn’t occur in the minutes and hours during which its functions returned?” (cf. Waking Up, 179). This is an important point, and I agree with Harris, and for essentially the same reasons that Harris adduces.
First, there’s no non-problematic inference from the purely subjective features of an experience, especially under exotic conditions, to a conclusion about the temporal metric of the event (that is, the duration of the event as measured by some clock).
Harris nicely illustrates the point here.
[Alexander] also appears to think that despite their timeless quality, his visions could not have arisen in the minutes or hours during which his cortex (which surely never went off) switched back on. He clearly knows nothing about what people with working brains experience under the influence of psychedelics. Nor does he know that visions of the sort that McKenna describes, although they may seem to last for ages, require only a brief span of biological time. Unlike LSD and other long-acting psychedelics, DMT alters consciousness for merely a few minutes. Alexander would have had more than enough time to experience a visionary ecstasy as he was coming out of his coma (whether his cortex was rebooting or not). (“This Must be Heaven,” cf. Waking Up, 182)
Harris raises this point only because Alexander had in early interviews insisted upon the subjective features of the experience as evidence for its duration and the implausibility of the experience taking place when his cerebral cortex was presumably coming back online, just before waking from his coma. (For example, see Alexander’s appearance on the radio program Here and Now, Nov. 27, 2012.)
But even Alexander must reject this line of reasoning, for he’s acknowledged, for his own reasons, that there’s little correspondence between his experience of time in the NDE and the actual metric of earthly time (Proof of Heaven, 143). As he stated in his Talk to the Theosophical Society in America, “Time flow in that Gateway realm is very different from time flow here. . . and the amazing thing is it doesn’t take anything of earth time. It could happen in a second or it could take a century to unfold. It doesn’t matter because time flow and causality in that realm is a much higher order than in this realm.” So Alexander himself accepts a premise that undermines any inference from the purely subjective features of his experience to conclusions about its temporal metric.
In Proof of Heaven, and in subsequent interviews and talks, Alexander draws attention to a second approach to fixing the time of his NDE. He argues, howbeit in a reserved manner, that his alleged veridical perceptions during his NDE provide evidence that his NDE occurred during his coma.
My most this-worldly anchors in my experience, temporally speaking, were my interactions with Susan Reintjes when she contacted me on my fourth and fifth nights, and the appearance, toward the end of my journey, of those six faces. Any other appearance of temporal simultaneity between events on earth and my journey beyond it are, you might say, purely conjectural! (Proof of Heaven, 143)
This is the so-called “time anchor” argument widely discussed in NDE literature and proposed to establish the time of an NDE. Roughly stated, the NDEr reports perceiving events taking place in the world during the NDE. If the earthly events are known to have taken place at a certain time, then presumably this is evidence for when the NDE took place. The operative assumption here is: if some person S perceives x and x occurred at time t, then S’s perception of x occurred at time t. So, in Alexander’s case, he allegedly experienced communications from a person who tried, on particular occasions, psychically contacting him while he was in his coma, and he also saw faces that corresponded to actual people, five of whom were present at Alexander’s bedside shortly before he came out of his coma (Proof of Heaven, 108-10). If we regard these features of his experience as veridical perceptions, then, given the assumption of the time-anchor argument, it would seem that he had these perceptual experiences at specific points during his coma.
One fairly obvious response to the time-anchor argument would be to concede that Alexander had the veridical perceptual experiences (in his NDE) during his coma. This wouldn’t be extraordinary, and it certainly wouldn’t support the extrasomatic interpretation of his experience, unless there was good evidence that his cortex was shutdown at the time of the perceptions. As Harris noted, a significant number of coma patients have awareness during coma. Perhaps more significantly, there’s data that shows that even coma patients in a vegetative state can gradually transition into a state of minimal awareness, and then lapse back into a vegetative state (see Schnakers, Giacino, and Laureys). In the absence of functional data tracking patterns of brain activity, it’s difficult to see how Alexander can properly rule this out. Moreover, Alexander’s description of the human faces bubbling up out of a dark muck, and whose voices were unintelligible, wouldn’t be surprising as subjective features of a change in cortical activity shortly before regaining consciousness. While this would not explain the alleged communications with Susan Reintjes who was not physically present, if there’s any evidence for telepathic interactions between people, it’s draw from persons whose cerebral cortex is actually functional.
Now let’s be clear here. I’m not suggesting that residual and changing cortical activity, generating moments of minimal awareness, actually explains the apparently veridical features of Alexander’s experience. I’m rather pointing out a consequence of Alexander’s lack of functional data: if he doesn’t have adequate evidence that his cerebral cortex was shutdown for the entire duration of his coma, establishing on the basis of time-anchors that he must have had the experiences during his coma doesn’t do much for the conclusion he wishes to establish.
7. Living-Agent Psi and the Time-Anchor Argument
As Harris argued, though, even if Alexander provided good evidence that his cerebral cortex was shutdown for the entire weeklong coma, Alexander can’t know that he had his NDE during his coma. As suggested above, the time-anchor argument is widely invoked to refute this sort of counter-argument. But ultimately it’s unsuccessful at doing this, and largely on the basis of a claim that Alexander himself insists upon and that’s essential to his NDE account, the claim that living persons exhibit psychic functioning (psi) in the form of telepathy and clairvoyance.
More generally speaking, the only reason for accepting the extrasomatic interpretation of NDEs would be veridical perceptions within the NDE of events in this world. Veridical perceptions, if they’re not fortuitous, imply that we can’t adequately explain all NDEs as hallucinations, delusions, or purely fictional confabulations of a dying brain (or some other non-reality oriented cognitive process). And not all veridical perceptions during an NDE need to be time-anchors. So, for example, one apparently veridical feature of Alexander’s NDE was his encountering a beautiful young woman he later realized looked like a deceased sister he never knew he had, until this was discovered after his recovery. But, as we’ve seen, veridical perceptions can also importantly serve as time-anchors, helping fix the time of an NDE, ideally as taking place when the known degree of cognitive impairment of the NDEr would prevent a naturalistic explanation of the experience.
However, living-agent psi poses problems for the extrasomatic interpretation of NDEs. The most widely-advertized problem is that it offers an alternative explanation of the veridical perceptual experiences during some NDEs. More precisely stated, the living-agent psi hypothesis appeals to psychic functioning to explain how NDErs have unusual knowledge, but it’s an explanation entirely compatible with denying the extrasomatic interpretation of the NDE. And here’s the most salient point vis-à-vis Harris’s critique of Alexander—Harris himself acknowledges this alternative explanation.
In “Science on the Brink of Death,” Harris said:
Even if true, such phenomena might suggest only that the human mind possesses powers of extrasensory perception (e.g. clairvoyance or telepathy). This would be a very important discovery, but it wouldn’t demonstrate the survival of death. Why? Because unless we could know that a subject’s brain was not functioning when these impressions were formed, the involvement of the brain must be presumed. (cf. Waking Up, 173)
What’s particularly salient here is that even the extrasomatic interpretation of NDEs requires clairvoyance and/or telepathy to account for the veridical features of NDEs, for these exotic modes of cognition would be required to explain how an allegedly disembodied person knows about events taking place on earth. Harris doesn’t note this particular point, but it’s a necessary corollary of the extrasomatic interpretation. More importantly, although Harris states that telepathy or clairvoyance could in principle explain veridical features of NDEs, it doesn’t take much ingenuity to realize how living-agent psi undermines Alexander’s reasons for supposing that his NDE took place during his coma. Living-agent psi would include not only telepathy and clairvoyance but also precognitive experiences (a non-inferential or direct knowing of the future) and retrocognitive experiences (a non-sensory and non-inferential knowing of the past). From the viewpoint of parapsychology, which Alexander actually accepts, there are at least four possible hypotheses consistent with cortical shutdown:
(h1) Alexander’s NDE was a clairvoyantly and telepathically determined experience taking place during cortical shutdown.
(h2) Alexander’s NDE was a precognitively determined experience that took place before cortical shutdown.
(h3) Alexander’s NDE was a retrocognitively determined experience that took place after cortical shutdown.
(h4) Alexander’s NDE was a two-phased, phenomenologically fused psychic experience, part of which was precognitively determined (before cortical shutdown) and part of which was retrocognitively determined (after cortical shutdown).
If Alexander wishes to claim (h1), then he should be able at least to provide some evidence that favors (h1) over (h2), (h3), and (h4). But to date Alexander has not adduced a single fact that does this. And Kastrup, who also believes in psychic functioning, also fails to do this, despite the fact that Harris broaches the relevance of psi for the extrasomatic interpretation of NDEs. To this extent, Kastrup doesn’t address the wider range of implications of Harris’s critique.. And neither Alexander nor Kastrup has really penetrated the heart of the debate concerning the extrasomatic interpretation of NDEs, which is a debate within parapsychology and independent of materialist assumptions.
But there’s a more devastating issue here once we accept the empirical possibility of exotic modes of cognition such as extrasensory perception. As explained above, the only plausible basis for forming justified beliefs about when an NDE occurs would be the NDEr having perceptual knowledge of terrestrial events during an NDE, where the events in question have a known temporal index (i.e., as happening at some specific time or within some specifiable period of time), and the temporal index of the terrestrial event at least closely approximates the temporal index of the NDEr’s physical condition or brain state(s). In principle this would permit the desired inference:
(1) Alexander perceived x.
(2) x happened at t.
(3) At time t, Alexander had a perceptual experience of x.
Furthermore, now add:
(4) Alexander’s cerebral cortex was inactive at time t.
We can then infer:
(5) Alexander’s perception of x took place while his cerebral cortex was inactive.
This would essentially establish the extrasomatic interpretation of Alexander’s NDE.
I’ve already explained why Harris is correct about the lack of good evidence for (4), but consider here the time-anchor portion of the larger argument, namely (1) through (3). This would be fine to establish when Alexander had his NDE, unless we introduce non-conventional modes of cognition. A crucial assumption in the time-anchor inference is that it’s empirically impossible for a person to perceive an event x that occurs at time t at any time other than t. But if that’s true, precognition and retrocognition would be empirically impossible. Indeed, telepathy would also be impossible, for telepathy allows the possibility that one person could acquire knowledge (perhaps even perceptual knowledge) of a past event at some later time by way of causal interaction with the mind of some other person who had the (perceptual) knowledge. So there’s no way to consistently accept psi and rely on the time-anchor argument to justify beliefs about when an NDE occurred. In fact, since there’s no reason to accept the time-anchor argument unless you already accepted psi, for psi is required to explain how disembodied consciousness could have empirical knowledge of terrestrial events, the time-anchor argument is actually self-defeating. And the matter is worse in Alexander’s argument since one of the substitutes for x is an attempted communication between a psychic and Alexander, a communication that could be efficacious only if there was genuine telepathic interaction.
Harris doesn’t make the above argument, but it nonetheless confirms one of Harris’s main claims, namely that Alexander doesn’t have good evidence for determining when his NDE occurred. And I think it further shows why Kastrup is ill-equipped to offer Alexander much of a sensible defense on this crucial point.
In follow-up responses to his initial blog on Harris, Kastrup wrote:
I find it a stretch to imagine that a just-recovering brain, which has just begun to emerge from extensive damage, can confabulate not only such a highly complex, coherent, crisp, and ultra-real hallucination, but do so in the space of a few minutes or hours.
Again we see Kastrup retreating to the shelter of presumption and impressionistic judgments, when actual evidence is required. Moreover, to speak of a “just-recovering brain” and “extensive damage” is too vague to justify the kind of claim that needs to be made on behalf of Alexander’s experience. And Kastrup’s response is just as question begging as his reasoning we examined earlier. Since the extent of Alexander’s neuronal activity during his coma lacks adequate resolution, we’re really not in a position to rule out the empirical possibility that his cortex produced the experience upon being turned on again. Indeed, it’s hard to see how this is even improbable. Neither Kastrup nor Alexander has made that argument. Moreover, the skeptical doubt doesn’t require that Alexander’s NDE occurred immediately after the cortex was brought online. The point is rather that Alexander cannot sufficiently rule out the empirical possibility that his experience occurred at some time(s) when his brain was capable of producing complex phenomenology. After all, those first moments would be subjectively indistinguishable from the experience happening at any earlier point. And this point is reinforced, not diminished, by acknowledging exotic modes of cognition.
In the light of the above, when Kastrup says, “Alexander is in the best position to judge when he thinks it happened,” he ignores the points Harris has raised, as well as how the acceptance of psi undermines the claim to know when Alexander’s NDE occurred, even for Alexander himself. The bottom line is that we don’t know enough about the patterns of neuronal activity during or after Alexander’s coma (because we lack functional data), so we’re not in a position to justifiably say whether there were spikes of higher cortical activity and then a fall back into lower cortical activity or no activity at all, but we do know that this scenario has been demonstrated in other coma patients. So we can’t really adequately rule out Alexander’s NDE happening during phases of sufficient cortical activity during his coma. And, if we accepted Alexander’s claim of cortical inactivity during his coma, we equally can’t rule out his experience occurring before and/or after his coma. Admitting that human persons may acquire knowledge through telepathy or clairvoyance only weakens Alexander’s contention that he must have had his experience during a presumed phase of cortical inactivity.
8. Concluding Remarks
Kastrup raises a number of other objections to Harris, especially in “Sam Harris Proud and Prejudiced.” These are largely expressions of his antipathy towards Harris’s attitude and alleged condescension towards Alexander. For example, Harris points out that Alexander’s status as a neurosurgeon doesn’t make him an expert on matters that fall within the domain of neuroscience. (This distinction between a neuroscientist and a neurosurgeon, like the distinction between psychologist and psychotherapist, tends to go unnoticed by non-specialists.) Based on Alexander’s factual and conceptual errors, Harris also expresses doubts about Alexander’s scientific knowledge.
I don’t see that Kastrup actually refutes any of these points, which I’d say are reasonable observations but, as it happens, rather tangential to Harris’s main argument. This is why I’ve opted to ignore these issues in the interest of a deeper engagement with Harris’s main argument. Moreover, Kastrup fails to note a point that Harris himself insists upon in the article to which Kastrup is responding:
If Alexander were drawing reasonable scientific conclusions from his experience, he wouldn’t need to be a neuroscientist to be taken seriously; he could be a philosopher—or a coal miner. But he simply isn’t thinking like a scientist—and so not even a string of Nobel prizes would shield him from criticism. (cf. Waking Up, 186)
At the end of the day, scientists, philosophers, neurosurgeons, and yes, even someone with a Ph.D in computer engineering, will only be as a credible on a particular topic as the clarity and cogency of their reasoning on the topic. Alexander and Kastrup fail at this juncture.
To recapitulate: Cutting away the more peripheral aspects of his presentation, Harris argues that Alexander has not provided adequate evidence for accepting the extrasomatic interpretation of his experience because he has not offered adequate evidence for two crucial premises on which his conclusion, by his own admission, depends. Moreover, Harris shows why Alexander’s evidence is inadequate and what would be required for better and good evidence at these crucial points of his argument. Kastrup fails to offer a remotely plausible challenge to Harris on these crucial points, which I charitably propose is a consequence of Kastrup simply not understanding the dialectical structure of Harris’s argument.
Finally, it’s worth noting that Harris himself—contrary to what Kastrup suggests—has left the door open for consciousness persisting after death precisely because Harris’s skepticism and epistemic caution run in both directions.
The truth is that we simply do not know what happens after death. While there is much to be said against the naive conception of a soul that is independent of the brain, the place of consciousness in the natural world is very much an open question. The idea that brains produce consciousness is little more than an article of faith among scientists at present, and there are many reasons to believe that the methods of science will be insufficient to either prove or disprove it. (End of Faith, 208)
Since Kastrup doesn’t understand what Harris argues in the articles that he’s addressing, it’s not surprising, though no less egregious on that account, that he doesn’t understand Harris’s broader position on postmortem survival and philosophy of mind. True, nothing Harris says in his remarks in the End of Faith lends credibility to the conception of the afterlife that Alexander would like us to accept. Harris isn’t endorsing the plausibility of an afterlife in which we fly, with beautiful women, on the wings of large butterflies, as desirable of a future as this may be. Of course, his comments also don’t rule it out. Thus, when Harris says, in response to Alexander, that he’s “open” to the sort of claims Alexander makes, he’s exhibiting an attitude and stating a viewpoint he’s expressed in print since the publication of the End of Faith in 2004, four years before Alexander even had his NDE.
Bernardo Kastrup’s critique is perhaps well-intentioned, but it’s an abject failure in point of logic. It serves as a painful reminder of just how ill-equipped defenders of NDEs as evidence for survival are at navigating the unavoidable territory of conceptual analysis, evidence evaluation, and the making of cogent arguments. Perhaps the most disappointing aspect of the kind of critical analysis that Kastrup attempts to offer is that, by systematically misrepresenting Harris’s actual criticisms, the road forward in the NDE debate is shrouded in further obscurity when greater lucidity is desperately needed.
Bernardo Kastrup’s response to this blog (12/22/15)
My response to Kastrup’s response (12/25/15)
Michael Prescott’s response to this blog (1/4/16)
My response to Michael Prescott’s response (1/5/16) (published in Prescott’s blog)