Against the Afterlife: The Argument from the Neural Localization of Mental Functions

It’s hard to believe but even in our day and age, there are plenty of fairly distinguished philosophers who defend the existence of mental life after brain death.  My neuroscience colleague Sonya Bahar and I have written a paper explaining why what we know about the brain makes a strong argument against the afterlife.

The paper is due at the end of this month for a volume edited by Keith Augustine.  If anyone cares to take a look and tell us where we went wrong, we’d love to hear it.  Please contact me and I’ll send you a copy of the paper.

Abstract:  The paper samples the large body of neuroscientific evidence suggesting that each mental function takes place within specific neural structures.  For instance, vision appears to occur in the visual cortex, motor control in the motor cortex, spatial memory in the hippocampus, and cognitive control in the prefrontal cortex.  Evidence comes from neuroanatomy, neurophysiology, neurochemistry, brain stimulation, neuroimaging, lesion studies, and behavioral genetics.  If mental functions take place within neural structures, mental functions cannot survive brain death.  Therefore, there is no mental life after brain death.

14 Comments

  1. I suppose one could defend a more abstract conception of mental life (pure awareness) that does not require specific mental functions. Mental functions such as vision, etc. appear to be specific, unlike “mentality” in general.

  2. Interstellar Bill

    You are correct to note that the mind’s survival is a separate question from its non-physical nature. You should have quite while you were ahead, rather than bringing up wishful thinking. After all, suicide victims are wishful thinkers too, wishing for non-survival.

    Instead, you start off your paper by assuming what you’re supposed to be proving (a tactic that is itself a species of wishful thinking!). Asserting that conceptual thought, which is manifestly non-physical, has the same material dependence upon the body as digestion (which is totally physical), is logically equivalent to belief in non-survival. This most hoary of utterly dead canards (mentation=digestion) is trotted out as though it was the latest philosophical innovation. Is that the best you can do as a contribution to a centuries-old debate?

    The rest of your paper, replete with the customary neurology frills, is but mere window-dressing for plausibility of the assumption, not proof. There was no mention of the still-intractable symbol-grounding problem, for example.

    First you need actually to prove that thought is nothing but matter, not merely opine the idea, which is all that materialists ever feel obliged to do. It’s not enough to note that mental activity depends upon the brain, and then hurriedly leap to physicalism. If that was correct then the mythical HAL 9000 would indeed have become conscious back in 1992. The reason that did not happen is that computers crunch numerals (which are material symbols for numbers), not the numbers themselves, which are immaterial entities forever beyond the reach of any Turing machine. The conceptual confusion between numerals and numbers (ironically shared by numerologists) is at the heart of the AI project, as well as your neural reductionism. In a similar vein, neural activity is not mind but merely its servant.

  3. Eddy Nahmias

    I haven’t read the article, but do you consider the possibility that God recreates the body and brain, perhaps in a more permanent form (less susceptible to decay) and/or in its most perfect state (i.e., not after Alzheimers), in a physical or quasi-physical heaven?

    I think this idea is crazy, but it’s not impossible. And I think it’s most consistent with the idea of the afterlife in the bible, so far as I understand it.

    I mention it only because I use it to motivate the idea that physicalism need not entail no afterlife and that a Cartesian soul is actually an implausible and unattractive way to live after our bodies die (e.g., how would we find grandma?).

    It’s entirely consistent with your thesis that there is no mental life without a functioning brain (or functional equivalent of a brain?), but it does not rule out an afterlife or even eternal life.

  4. gualtiero

    quentin, use use the term “mental function” very broadly, to include awareness.

    Interstellar Bill, you are right that we are not the first people to defend the claim that mental functions are the manifestation of the brain. i don’t think we ever claim to be first. but contrary to what you suggest, we do argue for our conclusion; we don’t simply make an assertion.

    Chris, thanks.

    Eddy, thanks for this important point. in the paper we have a section about that. our main reply is that this materialist approach to the afterlife based on constructing a replica of you is not a way for _you_ to survive. your replica is not numerically identical to you, so your mental life is still gone even after your replica is constructed.

  5. Bill

    A speculation based on recent readings, which may have gone over my head:

    Do Saul Kripke’s rigid designators actually exist? If they do, do they (still) exist even in possible worlds where the thing they refer to does not (currently) exist?

    If so, could one (re)create the thing to which the rigid designator refers in a world in which the refererent had formerly existed?

    If one could do so, would Kripke’s rigid designator then somehow require numerical identity?

  6. If you use mental function in a broad sense which includes awareness, and if you claim that mental functions take place in specific neural structures, then you claim to have solved the mind-body problem, which is a rather extraordinary claim… If not, then one could still believe that pure awareness is not located in neural structures and can survive to death. This is not my position, but I find it hard to have any certitude on this point.

  7. Eddy Nahmias

    Gualtierro, I should have put it differently. God does not recreate the body; God resurrects the body. Jesus rose from the grave, right? Shoot, but why are there so many bones left? And if it doesn’t happen until the End of Days (October right?), then the brains will not be around to resurrect–God would have to recreate them. OK, this idea is sounding less and less plausible. But I think it’s what van Inwagen defends somewhere, no?

  8. Hi there came across your article I have a few things to say about it.

    You and your colleague said:

    Abstract: The paper samples the large body of neuroscientific evidence suggesting that each mental function takes place within specific neural structures. For instance, vision appears to occur in the visual cortex, motor control in the motor cortex, spatial memory in the hippocampus, and cognitive control in the prefrontal cortex. Evidence comes from neuroanatomy, neurophysiology, neurochemistry, brain stimulation, neuroimaging, lesion studies, and behavioral genetics. If mental functions take place within neural structures, mental functions cannot survive brain death. Therefore, there is no mental life after brain death.

    Sure mental functions are strongly correlated with neural structures. If mental functions were within neural structures the hard problem of consciousness would be solved. But it isn’t. Its an assumption that mental functions are within neural structures but the two scientists believe they can make a conclusion on the evidence they have gathered over the past decades.

    Your article also puts up a good straw man without mentioning any of the evidence from the other side.

  9. I’d just like to make a comment on the author’s dismissal of the possibility for survival under physicalism. I personally am not a physicalist/naturalist/materialist, indeed I regard such a position as transparently false. I also think survival is fairly likely given all the evidence and philosophical considerations. However, even if physicalism were true, it is quite clear that survival is possible. Or at least survival is possible (assuming naturalism) in the same sense that we can be said to survive from one day to the next.

    The author illustrates his argument by the following thought experiment:

    ” imagine that teleportation is invented. A teleporter disintegrates your current body, extracts precise information about the location of each particle that constitutes you, and makes an exact particle-by-particle replica of you in another location. To go from New York to Paris, says the advertisement, you can take a plane, which takes seven hours and costs $1,000, or take the teleporter, which takes only a minute and costs $100. Which one would you take? If you are in doubt, consider a more advanced teleporter. It makes a copy of your body by scanning your present body without destroying it. Now it should be pretty clear that after you enter and exit the teleporter in New York, you are the person who is still in New York, while the new body in Paris is a mere replica distinct from you. Regardless of how many replicas are made and whether making replicas requires the destruction of your current body, your replica is not you. No one can make your replica numerically identical with you—not even god (contra Baker 2011)”.

    Sorry but he cannot believe this. It is inconsistent with naturalism/physicalism/materialism. Under naturalism there is no distinction between numerical and qualitative identity. At that instant when the replica is created the replica necessarily must be you if it is physically identical. To deny this is to affirm that what “you” are is something over and above the totality of your physicality.

    But let’s press this further. The replica will look the same, share the exact same character traits and in general be absolutely psychologically indistinguishable from the original. Moreover this ostensibly teleported person will have memories of her life before being teleported; she will remember standing in the teleportation booth, experiencing a sudden shift in perspective, and finding herself in the destination booth. In every way this newly created person will feel herself as being simply a continuation of the original and that she has merely instantaneously transported from one place to another.

    So to deny that the replica is the very same person is not only to deny that ones total physicality fixes identity, but also that the totality of ones psychological states, including memories, fails to fix identity too! Of course under any materialist based metaphysic the former will entail the latter, but it is pertinent to

  10. OK I submitted a comment, but it hasn’t appeared yet. Perhaps because it was too long so I’ll resubmit in 2 parts:

    I’d just like to make a comment on the author’s dismissal of the possibility for survival under physicalism. I personally am not a physicalist/naturalist/materialist, indeed I regard such a position as transparently false. I also think survival is fairly likely given all the evidence and philosophical considerations. However, even if physicalism were true, it is quite clear that survival is possible. Or at least survival is possible (assuming naturalism) in the same sense that we can be said to survive from one day to the next.

    The author illustrates his argument by the following thought experiment:

    ” imagine that teleportation is invented. A teleporter disintegrates your current body, extracts precise information about the location of each particle that constitutes you, and makes an exact particle-by-particle replica of you in another location. To go from New York to Paris, says the advertisement, you can take a plane, which takes seven hours and costs $1,000, or take the teleporter, which takes only a minute and costs $100. Which one would you take? If you are in doubt, consider a more advanced teleporter. It makes a copy of your body by scanning your present body without destroying it. Now it should be pretty clear that after you enter and exit the teleporter in New York, you are the person who is still in New York, while the new body in Paris is a mere replica distinct from you. Regardless of how many replicas are made and whether making replicas requires the destruction of your current body, your replica is not you. No one can make your replica numerically identical with you—not even god (contra Baker 2011)”.

    Sorry but he cannot believe this. It is inconsistent with naturalism/physicalism/materialism. Under naturalism there is no distinction between numerical and qualitative identity. At that instant when the replica is created the replica necessarily must be you if it is physically identical. To deny this is to affirm that what “you” are is something over and above the totality of your physicality.

    But let’s press this further. The replica will look the same, share the exact same character traits and in general be absolutely psychologically indistinguishable from the original. Moreover this ostensibly teleported person will have memories of her life before being teleported; she will remember standing in the teleportation booth, experiencing a sudden shift in perspective, and finding herself in the destination booth. In every way this newly created person will feel herself as being simply a continuation of the original and that she has merely instantaneously transported from one place to another.

    To be continued in my next comment . . .

  11. Continued from my previous comment . . .

    So to deny that the replica is the very same person is not only to deny that ones total physicality fixes identity, but also that the totality of ones psychological states, including memories, fails to fix identity too! Of course under any materialist based metaphysic the former will entail the latter, but it is pertinent to stress this point.

    So how does the materialist escape the seeming paradox the author alludes to? Imagine the following scenario. Imagine that every infinitesimal fraction of a second you are getting teleported from place to place. Obviously if you keep your eyes open you’ll just see a confusing blur. But you could close your eyes, and everything would seem to be normal. You could be thinking of a problem, daydreaming, or whatever. Nothing would seem different then when you have your eyes closed normally, except in the teleportation scenario you are continuously being killed and spontaneously coming into being every infinitesimal fraction of a second!

    Now if we suppose that precisely this is happening in our second by second everyday existence then there is no paradox.

    What this means then is that the materialist has to reject the notion of a persisting self. That’s all an illusion. There is only the sense of a self, but that sense corresponds to no real self.

    Let me try to be more clear about this. If the original body is killed at the precise moment of replication then from the perspective of the person being teleported she will seem to “jump” to the remote destination. But of course there’s no reason at all why the original should be killed at that particular instant. Perhaps we might delay the termination of the original; by an hour say. But then this creates the interesting scenario whereby it seems to the person that at the precise moment of replication she will have a 50/50 chance of either suddenly “jumping” to the remote location, or simply remaining where she is with the unpleasant prospect of being killed in an hours time!

    If you think this represents a paradox then you haven’t understood what I’m saying. Should naturalism/materialism be true then we do not even survive from one second to the next. The overwhelming feeling we are persisting selves is all a horrible illusion. The original person will die in an hours time. But intellectually this ought not to perturb her in the slightest since she is effectively “dying” every infinitesimal fraction of a second anyway. Of course psychologically she is likely to be very frightened indeed! This reflects the fact that we are all instinctively strong dualists, or at least that we are persisting selves i.e substantial selves. It is overwhelmingly counter-intuitive to suppose otherwise.

    The author’s thought experiment reveals that he too is instinctively a strong dualist. In his paper he derides substance dualism, yet affirms that the self is substantial in his teleportation thought experiment!

  12. tim

    It’s hard to believe but even in our day and age, there are plenty of fairly distinguished philosophers who defend the existence of mental life after brain death.

    Firstly, what a ridiculous statement…in OUR day and age. Everybody who has ever lived has said the same thing so what value has that cliche got ?
    Secondly, it certainly is hard to believe…hard to believe that such a large body of evidence including NDE’s, shared NDE’s, DBV’s, ESP, mediumistic communication, reincarnation etc etc is written off so that materialism prevails.

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