30

As Alzheimer's disease kills off neurons, a person's personality and cognitive abilities gradually fade away. Doesn't this suggest that the self or "soul" is simply an emergent property of the brain's physical structure and function, rather than some immaterial essence or spirit that exists independently of the body?

The classical notion of the soul as an immaterial, eternal essence that exists independently of the physical body is challenged by the way Alzheimer's systematically dismantles a person's mental faculties and sense of identity over time. As the disease destroys neurons and neural connections, the patient's personality, memories, and very "self" seem to disintegrate, suggesting that these aspects of the human experience are products of the brain's physical structure and function, rather than some non-physical soul.

16
  • 19
    Although I tend to agree that alterations to the brain (or intoxication with various neuroactive substances) provoking alterations of the behavior do point toward physicalism, the usual counter by dualists is that, even if it is easily demonstrable that neural activity commands our moves and behviour, it is possible that the soul interacts with our body by the means of the brain. In that case neuronal alterations would interfere with our ability to control or get input from the brain, which would explain the observed phenomena. There is no way to definitely prove that there is no soul.
    – armand
    Commented Apr 15 at 4:14
  • 6
    @causative that would have to be addressed to the proponents of the argument. What they probably would tell you is that even if memories are stored in the brain (which, iirc we know to be a fact as neuron circuits do their job by reactivating perception neurons that were activated together in the past), it does not preclude our decision making from being done in the soul, or something. That's the nice thing with magic: you can't prove it does not exist.
    – armand
    Commented Apr 15 at 4:37
  • 3
    @causative you're not reading me. This line of reasoning will never force a dualist to admit there is no soul, they'll just tell you that the brain is involved with interpreting the world around us and executing the decision, but that the decision is in the soul, which you can't demonstrate. Just like you can't demonstrate there is no God. I'm not saying their argument is good, just that it exists and is unfalsifiable.
    – armand
    Commented Apr 15 at 6:00
  • 4
    @DavidGudeman: Plenty. If you've seen your loved ones taken by dementia you know it. Their personality becomes other than very easily.
    – Joshua
    Commented Apr 15 at 17:46
  • 3
    Answering seems to require an agreement on what the soul even consists of. The most upvoted answer right now says that memory is not part of the soul. I imagine it's possible that some people may also see personality as not part of the soul. It doesn't seem difficult to remove everything observable from it and so claim that there can still be something left to be called a soul that doesn't rely on a body in order to exist.
    – JoL
    Commented Apr 16 at 7:35

19 Answers 19

23

Alzheimer's disease (and other brain disorders with some observable physical effect along with psychology and neuroscience generally) does seem to make the existence of an immaterial soul much less plausible and less useful or necessary for explaining anything.

Science tells us that:

  • Different parts of the brain correspond to different neural functions.
  • Physical changes in the brain affects your memories, your emotions, your ability to reason, etc.
  • People consistently behave in certain ways given certain environments and stimuli (which isn't direct evidence against a soul, but does support the claim that we're merely the result of our biology and environment).
  • Etc.

But the existence of a soul is ultimately unfalsifiable, so someone can accept all of that and still hold that there's an immaterial soul by saying roughly either of the following:

  • The soul sort-of mirrors the brain, with some unclear connection between the two (which seems to render the soul completely unnecessary as a hypothesis)
  • There's some separate part of your being that is your soul (but we have no reason to think such a part exists, we don't know what that part would do, and we already know parts of your physical brain affects memories and emotions and your reasoning ability, so does the soul exclude all of that?)

Also, if one accepts evolution and common descent, the human-only soul is also a lot less plausible, given the unclear line between humans and other apes. Related answer.

1
  • 2
    I'm afraid that without a clear definition of what a soul is and what a soul does (and more importantly, what it does not), the issue collapses to "whatever you believe". Which makes the whole issue unfalsifiable by default. But one evidence that the soul does not hold memory (at least not very well) is that if you assume reincarnation of the soul is a thing, the vast majority of these reincarnated souls do not remember their previous lives. - - - The word "assume" above is lifting more than Atlas, I'm afraid. Commented Apr 16 at 19:14
22

No, not really, the disease is just evidence for the corruption of the region of the brain that houses memory due to aging. It is just evidence for the degeneration of the human body and consecutively the mind as one grows older. Soul does not mean memory. Memory does not mean soul. In any philosophy i.e., medieval to modern, these two things are not necessarily mutually inclusive. I would say it would make more sense to syllogize consciousness and soul rather than memory and soul.

Edit: Consciousness is more multifaceted than just its parts i.e., memory, thoughts, self awareness, emotions and other arising traits. Alzheimer's might affect these attributes to some degree but that doesn't mean it annihilates (devoid) one's consciousness, let alone the evidence for the existence of one's "soul" (which as mentioned in the comments might be vaguely defined).

14
  • "the region of the brain that houses memory" - but that assumption itself isn't necessarily obvious to someone first getting introduced to the question of Physicalism, and so the fact that we can say "physical regions of the brain store memories" at least has to be a little bit of evidence for Physicalism
    – TKoL
    Commented Apr 15 at 9:37
  • 1
    @TKoL I mean there isn't just one place in the brain that houses memory its not like we can isolate only one part of the brain and retrieve memory from it even if that was the case that is not how we remember our memories, it is usually a network of neural connections in different parts of the brain what I meant by the region that houses I meant to say all the neural connections and pathways that makes memory accessible for humans, because the whole brain and the nerve cells gets affected, this was what I was trying to get at, just like OP mentions, but atleast we know there is a physical part
    – How why e
    Commented Apr 15 at 10:51
  • 2
    If you believe in a soul that can exist without a body, and at the same time that memories are housed in the brain, I would imagine that's an uncommon view of the soul, right? Because, in the afterlife, a person wouldn't be able to recognize anybody.
    – JoL
    Commented Apr 16 at 7:55
  • 1
    @JoL I don't think it is uncommon also I don't think anyone should recognize anybody else in the afterlife. The afterlife is nothing like the physical realm we interact after all, there is no body (in the earthly sense)
    – How why e
    Commented Apr 16 at 7:58
  • 6
    This answer and its comments hit at the core problem with this question, which is that there's very little consensus on what a soul actually is, what parts of a "person" it does or does not contain, and how it interacts with the physical world.
    – Dan Staley
    Commented Apr 16 at 23:12
5

Short Answer

Absolutely yes. The simplest spiritual dualist model, in which personality is off-board, and interacts with the body in the mode of a drone operator with a drone, is challenged by all observations of selfhood being degraded or affected more than a drone operator would be by neural or chemical influences.

Longer Answer

Straightforward falsification is itself refuted as a science methodology, and instead counter-evidences call for patches to a theory. The decline of predictability/power of a model as it complexifies in the face of test data is how one evaluates the plausibility consequences of observations.

There are ways to patch spiritual dualism to be compatible with Alzheimer's, mechanical brain injury, chemicals affecting consciousness, etc. There are not many spiritual dualists who adopt methodological naturalism, and I have not seen anyone else's proposal on this issue, but I will offer mine.

  • Given that we observe willing affecting the body, as well as body affecting willing, two way causal spiritual interaction is a first order plausible model
  • But the over 1000X advantage of thruput for neural processing over spiritual processing revealed in the Thinking Fast and Slow studies, shows that there are significant limits of processing thruput for the spiritual side of spiritual dualism, and evolutionary benefit for neural mental process assist to what is nominally a spiritual feature.
  • If the thruput of a spiritual mind is fungible, then allocating most of that thruput to coordinating the mental function assist by neurons is evolutionarily advantageous.
  • Damage to the neurons, chemical affects, etc. while the spiritual side is so allocated, would be seen as a loss of consciousness function.
  • The possibility of recovery of full mental function for a spirit upon disengagement from ensoulment, due to fungible reallocation, is a possible outcome for this model, and is testable under OBE, NDE, past life, and ghost telepathy experiments. The data from these experiments support the fungible-reallocation model revision.

When one is evaluating the plausibility of a scientific model, this is a comparative process, as almost all models encounter similar contrary data, and need to be complexified to address it.

Note that the most widely postulated alternative model family is physicalism, which has for the last 150 years been unsuccessful in even coming up with a valid complexification that can address the hard problem of consciousness. The inability for physicalism to explain consciousness is what is behind the "Delusionist" school of thinking, which tries to deny the existence of consciousness due to the failure of these models to account for the data. A model that needed to be complexified, but now matches the data, is always superior to one that instead denies the data.

4
  • 1
    Maybe we just don't have the right model yet? How long between Galileo and Einstein?
    – Scott Rowe
    Commented Apr 15 at 17:04
  • 3
    @ScottRowe -- Yes there was a lot of time between Newton and Einstein. But Newton's model matched the data he had -- physicalism never has. How long for physics to get modified once it was clear Newton was wrong? 30 years? Also, the number of PEOPLE trying to revise physics over that time, was significantly less than the number of people trying to modify physicalism, as the size of the philosophic and scientific communities have grown dramatically. Failure X person-years is quite high for physicalism.
    – Dcleve
    Commented Apr 15 at 17:18
  • I haven't really seen soulism succeed though.
    – Scott Rowe
    Commented Apr 15 at 17:59
  • 1
    @ScottRowe -- Soulism has a spotty record. The most notable failure was in biology in the early part of the 20th century, when Vitalism proved not to be very useful in characterizing cellular structures. The biggest successes have come in parapsych. Remote viewing is basically shamanic spirit journeys. osf.io/preprints/psyarxiv/r9yw5
    – Dcleve
    Commented Apr 15 at 21:31
5

No.

If you allow for the existence of the soul, then the question of how the brain and soul interact arises.

Alzheimer's and its impact on personality, at most, would indicate that the condition of the brain impacts the expression of the soul.

It would not be an unreasonable hypothesis to state that, by some mechanism, as Alzheimer's progresses, the soul remains intact and unaltered but becomes constrained in its action, leading to the observed symptoms.

This would not be without precedent. Mental illness has, in the past, been blamed on all manner of metaphysical influences. In particular, the four humors theory blamed melancholy on excessive black bile. While we now know that these humors don't exists, it was, at the time, a theory that realized that dysfunctional internal processes can affect how we present to the world.

Today, we may have a more refined understanding of the internal workings of the human body, but that does not preclude the existence of the soul.

4

That's one possible conclusion, but it does not constitute a proof. Neuroscientist David Eagleman, in his book Incognito, explains why this isn't so using the analogy of a radio. A radio is a physical object, which plays music. If you damage the radio, you damage the sound quality of the music. If the radio degrades enough, the music stops entirely. As a naive conclusion, it's reasonable to think that the radio is creating the music, and that destroying the radio destroys the music. But in fact, the radio is just a receiver. As ludicrous as it sounds to say that some distant source is beaming the music inaudibly through invisible waves that penetrate walls and other solid objects, that's exactly what's happening.

The brain is a physical object, which seems to be the seat of the mind. As the brain degrades, the conscious mind also appears to degrade, nor can consciousness be maintained in the absence of a functional brain. But if we accept that "soul" might be broadcast from a remote source ("God") then the disappearance of the mind isn't a proof of the non-existence of the soul.

To express this in a different way, it has never been the position of most religious people that "the soul" is identical with "the mind", and therefore that the disappearance of the mind means the extinction of the soul. "Mind" is the more accepted (although not uncontroversial) concept in the modern scientific discourse, but it does not fully capture the notion of soul in a way that would allow this argument to succeed. In other words, this is (an illegitimate) proof by redefinition. Once we reduce soul to mind, then the disappearance of the mind is the death of the soul by definition--our conclusion is hidden in our assumptions.

6
  • +1 What a great response, beautifully written and well thought. Couldn't have said it better!
    – How why e
    Commented Apr 17 at 21:04
  • You are right the definition matters and there isn't a clear cut definition.
    – How why e
    Commented Apr 17 at 21:05
  • 2
    We can take a radio transmitter off the air. Since we can't seem to find the soul transmitter, it feels like the analogy is borrowing a lot. We can manufacture invisible causes, but it doesn't make a compelling argument.
    – Scott Rowe
    Commented Apr 17 at 22:02
  • @ScottRowe a great many people find the possible existence of some form of 'higher' or 'greater' consciousness to be a very compelling argument Commented Apr 18 at 0:53
  • 2
    @BugCatcherNakata there's probably a good explanation for that. But it doesn't affect the truth of the claim, no matter how many people believe it. All those people should get together and prove it once and for all. Or, we could set the question aside and move on to other things.
    – Scott Rowe
    Commented Apr 18 at 10:42
3

Personality and cognitive abilities are not the self, even though they are deeply cherished parts of the self. Their corruption alone doesn't make a person any less a person. There is something that a person with Alzheimer's has (or, perhaps better, is) that makes them different from dead matter. That something, if anything, is what the soul is.

To analogize, I notice a peculiar inability of those with an amputated left arm to ball their left hand into a fist at will. By altering their matter, they've lost a capacity they once had. Does this prove that there is no such thing as a soul? I might argue on the contrary. The fact that the hand becomes incapable of being balled into a fist at will after being separated from the body suggests there is something the hand partakes of while it is part of the body that it no longer does once separated. That something is what some people call a soul. A hand is a hand and not just organic matter by virtue of its participation in an organized, living body, i.e. by being subject to the soul.

More provocatively: is it okay to murder someone with Alzheimer's who, as you say, has had their mental faculties and sense of identity dismantled? If not, why not? What property does their matter have that makes it wrong to kill them? This property is, again, what some might call a soul.

5
  • 1
    Fun fact. People can move amputated limbs; and it's sometimes necessary to uncramp them (a portion of amputation phantom pain is the amputated limb stuck in an unnatural position). Amputated limbs can't manipulate the world though.
    – Joshua
    Commented Apr 16 at 2:16
  • Surely you don't mean that a person can move the hand on an arm that has been cut off? If you're talking about something like phantom limb syndrome, though, I think I understand, and that is pretty interesting. Commented Apr 16 at 2:17
  • 1
    Never heard it called a syndrome; it's the natural way of what happens. The brain has a map of the body within itself; cutting off the limb doesn't take it off the map.
    – Joshua
    Commented Apr 16 at 2:18
  • Is this what you're talking about: pubmed.ncbi.nlm.nih.gov/17684875 Commented Apr 16 at 2:20
  • Here's a better match. pubmed.ncbi.nlm.nih.gov/21397901
    – Joshua
    Commented Apr 16 at 2:21
3

Why does it have to be Alzheimer's? What about getting drunk? Getting drunk is a bodily phenomenon that affects the mind, and people have known about it for millennia and still believed in souls.

What about illnesses in general? For as long as humans have been humans, we've known that getting sick affects the mind. It makes you feel down, it keeps you from thinking straight. And yet people have still believed in souls.

The only reason the existence of the soul is a problem in the modern mind is because we take a mechanistic view of the physical world. Therefore, the soul, which isn't mechanistic, must be a different thing from the body, which is physical and hence must be mechanistic. So we need to either solve the problem of how the body and soul interact, or dispense with souls.

But this view is wrong to begin with. Neither the body nor the soul is a "thing." There's only one thing, the human, of which the body and soul are just parts. The whole human unit functions under its own rules, not the rules of mere matter nor of pure mind, which the body and soul follow in tandem.

Alzheimer's challenges the idea of the soul? Alright, then. The placebo effect challenges the idea of a purely physical body. The existence of logic and mathematics challenges the idea of a mind formed purely from the brain. After all, the physical is always particular, so how can we form ideas of the universal if our minds are purely physical? And no, an AI-like trial and error algorithm is not a sufficient explanation, because universal ideas apply to things we've never seen before.

I don't expect you to suddenly accept my views or anything, but I hope this gives you a clearer idea of the position you're trying to argue against.

1
  • I would expand "There's only one thing" to be: that which is - everything.
    – Scott Rowe
    Commented Apr 17 at 21:43
2

It was suggested that I elaborate my Comment in to an Answer, so don't shoot the messenger. One way to reason is to use analogies and metaphors. Sometimes the metaphors are too colorful and warp thinking. But I approached this question as being a form of communication between prospective soul and visible body. Does communication support the idea of a soul?

If we think of an ordinary phone connecting you and another person, that could be like the mind connecting with the soul. Using the metaphor, if your phone started having problems relaying texts and calls, would that cast doubt on the other person existing? Only if communication completely ended and you couldn't tell if it was your phone or that the other person stopped answering. But you still feel that there must have been another person (or, soul, in the metaphor) because it seems impossible that a handheld device could mimic the complex communication of another 'you'. We don't feel replaceable by a phone, just yet.

So the other side of the connection could feel too complex for just a brain to fabricate, like how I wondered as a child how they got all the musical instruments in the stereo, or all the little people inside the TV.

So it seems like I am arguing for a soul. But we don't know the capacity of the brain and mind, because it is too complicated for us to understand. (If we could understand the blessed thing, it would be pretty disappointing.)

Arguments about souls run aground on the fact that we can't see any difference that they could visibly, definitely make, unlike people at the other end of a call who come by and we can see them. The question seems not well put, because the metaphor says that something is missing.

2
  • 1
    The "phone" analogy has always seemed a little weak to me. If damaging the phone caused my friend on the other end to develop memory problems, I think it would be very strong reason to believe that that friend's memory exists primarily in my phone. If damaging the phone in a different way caused them to become irritable and short-tempered, that would be evidence that their emotion regulation also exists primarily in the phone. With enough of a catalogue of effects of possible damages, it would be hard to find parts of my friend that don't primarily exist in the phone.
    – Tim C
    Commented Apr 17 at 19:21
  • 1
    @TimC it is a strong analogy if it better supports one conclusion or the other.
    – Scott Rowe
    Commented Apr 17 at 21:54
2

As far as I can tell, nobody earnestly would suggest that the brain does not have some functions, like memory, pre-processing of data coming in from the senses, processing input and output from motor nerves, processing some emotions (especially deeply ingrained ones like fear, fight/flight responses) and so on and forth.

Many of these functions can be proven by looking at brain damage, be it via Alzheimer's, Mad Cow's disease, or plain old physical damage caused by bullets, sharp implements and so on and forth.

One thing that is still considered a hard problem is that humans seem to have a feeling of a "self" or "me", or an "observer" that is somehow observing the input from the senses (and this includes things we don't usually count as a senses, like thoughts, which if you meditate, very clearly are also happening very much on their own and are simply "observed").

It is absolutely unkown whether this "self" is an illusion or not; whether it is purely physical; or whether there is some non-physical "soul" which somehow lives out of reality as it is known to us. Sure, you find many people who tell you otherwise (i.e. who are totally convinced of some variants of those questions), but there definitely is no concensus.

It is the same as for religion or other "spiritual" questions: if you believe that something is the case, then things follow a very different logic for you. I.e., if you believe in a soul, you can easily come up with reasons why Alzheimer's does not disprove the soul (for example by positing that the brain is just an interface between body and soul). As someone who does not believe in a soul, Alzheimers does not help to disprove anything because to disprove a soul, you would need first to define or figure out what the soul actually is.

Same as science-vs-religion, brain science is ever more encroaching on all kinds of aspects in this regard. It is not a totally far-fetched standpoint to define the "soul" as all parts of the brain whose function we have not quite understood so far (i.e., a great many of them). This means that over time, as brain science figures this stuff out, the "turf" of the soul would become ever smaller. Whether it will disappear completely is the same question as whether science will ever completely "remove" religion. And even if we were able to explain absolutely every known feature of human brains scientifically, including what the "observer" is, I am sure that this would not convince people who believe in the soul of its non-existance.

The reason being that almost by definition, the soul is not subject to scientific approaches, so science cannot "disprove" it. Same as religion in general is not subject to scientific approaches, so science cannot "disprove" religion either. They are disjunct concepts.

2

What is a soul? At the least it's whatever is making these moral decisions I'm going to get judged for.

What is a brain? It's that gooey hardware that turns stimuli into reaction.

Does Alzheimer's degrading the performance of my brain disprove my soul? Nope. You can burn down the casino and still leave the dice intact. Whether fire proof dice exist is another question altogether.

Alzheimer's doesn't prove anything here any more that death does. Whatever a soul is, our time casually interacting with them in this world is limited. After that their continued existence is only supposed by those who believe in object permanence.

2
  • Souls without brains don't seem to make moral decisions, as best I can tell. What we would need is proof of continuity: reincarnation. If someone really recognizable came back, and people who knew them could confirm personal knowledge that they shared exclusively with the former person, it would be a start. The book "Children's Past Lives" covers this area. Confirming the hypothesis would require that masses of people keep encrypted diaries of interactions with people, that could be examined later to confirm the details. But there are not a lot of subject cases these days...
    – Scott Rowe
    Commented Apr 18 at 11:24
  • I often wonder how many humans have ever been born, ignoring the fact that a significant proportion didn't make it to age 5... If 8 billion are alive now, I guess something over 30 billion, but I have seen numbers over 100 billion. I guess it depends on when we define the first human being born. Confining the analysis to just the last century, is there a plausible number of reincarnation candidate cases? If not, why not? It seems like something people would be interested in and might make a stir about if it happened.
    – Scott Rowe
    Commented Apr 18 at 11:37
1

No.

If the soul is the "software" and brain is the "hardware", Alzhaimer disease is like running Windows in a Pc with RAM/disk deteriorating.

An example could be the Voyager probe. Its systems aren't 100% functional and NASA technicians are fixing problems here and there to let the mission continue.

1
  • 2
    I don't think this fits with the commonly accepted meaning of "soul" implied by the question. Speaking as a software engineer - a process cannot outlive the computer it's being run on. It may appear to a user that your apps restore themselves after your computer reboots, but those are actually new processes that are reading messages left behind by the old ones. If the "soul" is analogous to a software process, then it would still cease when the brain does.
    – Tim C
    Commented Apr 17 at 19:34
1

Doesn't this suggest that the self or "soul" is simply an emergent property of the brain's physical structure and function, rather than some immaterial essence or spirit that exists independently of the body?

No, it does not. Or at least it doesn't until one defines "self" or "soul" more carefully to ensure the individual you are suggesting to agrees with the meanings you are using. That being said, it is quite common in philosophy to talk about the "mind," a word which is a different word from "brain." If one chose to use the word "mind" instead of "self" or "soul," I think it would be fair to say the deterioration due to Alzheimer's suggests the mind and brain may be the same. "Suggests" is a great word because it's so much weaker than "proves" or even "demonstrates." You could enter a debate with a dualist and use this argument. You would, of course, need to follow it up because it's not a full argument in and of itself. But it could be done.

... and very "self" seem to disintegrate ...

This would be interesting to bring into a debate. "Seem" is a very subjective term. One is appealing to the assumption that the other individual, upon seeing this deterioration, must come to the same conclusion about the self you do. One would need to be ready for the other individual to simply disagree on this front.

And, of course, with any scientific theory we have to be very careful with correlation and causality. Just because one sees mental deterioration at the same time as seeing neural deterioration does not imply the latter causes the former. It is common to choose to think it does, but that's very much a choice of the individual.

I could easily see a dualist arguing that as the neurons deteriorate, the "soul" detaches from the physical body, and it is that detachment that causes the "self" to seem to fade away rather than the neural degeneration (making the detachment of the soul the proximate cause). Whether one finds this explanation to be more or less credible than yours likely depends heavily on decisions already made about the veracity of physicalism.

1

TL;DR: No.

What is a soul?

Some have observed that we can't answer this question without first addressing the question "what is a soul?". While there is some truth to that, I don't believe that answer is so ambiguous or lacking in consensus as to cause a real issue. Therefore, I will define "soul" thusly; that part of a person, spiritual (that is, immaterial) in nature, in which volition resides. Often the soul is believed to incorporate some aspect of memory and/or personality as well, although this seems debatable even by those who presume that souls exist. Additionally, it is unknown what abilities (if any) a disembodied soul possesses.

To those wondering about the nature of souls, I would recommend Orson Scott Card's Enderverse series, as his notion of "philotes" offers a plausible-seeming explanation as delivered from a more scientific, rather than theological, perspective.

What is the argument?

It should be noted that there are a variety of similar "attacks" on the soul of this form, with "damage-induced personality change" being a leading factor. Harry Potter and the Methods of Rationality also explores the question (from a Materialist perspective) and comes to a conclusion which I disagree with. In general, the question isn't limited to just Alzheimer's.

What shall we conclude?

For the sake of argument, we'll assume that the soul exists. The inability to explain the semblance of free will (whose existence is also sharply debated) in purely material terms would seem to argue in favor of this existence, but since the Question asks whether the claim of existence is undermined, for our purposes it is satisfactory to take the soul as a presupposition.

The main issue with arguments that "X disproves the soul" is that they tend to assume that the material realm cannot affect the spiritual realm. If this assumption is false, it's easy to see how physical (material) trauma could "spill over" into spiritual trauma, with corresponding effects on memory and/or personality, even if memory is a spiritual phenomena.

It seems more plausible, however, that the soul is only part of an intricately connected system, of which the material brain is an integral part. It seems beyond question that the brain (and even neurons outside the brain) play an integral role in processing both input and output signals. A person with no eyes, for example, can't see, and a person with nerve damage can't move their limbs. This, however, in no way invalidates the existence of the soul; it only indicates that the action of the soul is mediated by material substances.

Moreover, if we take a person's actions to be a combination of the material function of the brain and the soul, we can also see how chemicals or physical damage could alter a person's behavior, even if the soul exists. A good analogy might be to think of the physical person as a horse, and the soul as a rider. The rider "steers" the horse and provides higher-level guidance that what the horse can achieve on its own, but the horse also has the ability to override or ignore the rider. Even from a strictly material sense, we see this as in the case of reflexes wherein the body acts without instruction from the brain.

Consider also the brain as the "house" of the soul. Just as one's external environment influences behavior and mood, so too might brain chemistry "propagate" to influence the behavior of the soul. This seems especially relevant if we assume that certain functions, such as maintaining separation between one's "inner voice" and one's tongue or accessing memories, involve material function of the brain (hence explaining why chemicals can "loosen inhibitions", or why material causes can influence memory retrieval). Imagine, also, the frustration one must feel trapped in a body and mind that are not functioning correctly, and how the resulting frustration and sense of dissonance could influence personality.

Therefore, the long version is that such phenomena must certainly influence how we view the (two-way!) interaction of the soul with the physical world, but they do not preclude the existence of the soul.

1
  • If we can find things that are attributable to the brain, then what is left must be attributable to the soul. So what is on the list for soul at this point? If you say that we can't nail those kind of things down, then there is not an assertion being made, just an opinion.
    – Scott Rowe
    Commented Apr 18 at 11:16
1

Alcohol or drug use can affect one's memory and personality, at least for a certain period of time. So, you can ask this question very simply without using the term Alzheimer's disease :)

We often say that our body exists. We experience this fact with our senses. But the thing behind our body - the soul - always remains unchanged. Since the senses are parts of our body, the realization of truth like this is not necessarily through our senses.

I believe the explanation given in other scriptures is similar to this explanation given in the Bagavad Gita -- The soul is neither born, nor does it ever die; nor having once existed, does it ever cease to be. The soul is without birth, eternal, immortal, and ageless. It is not destroyed when the body is destroyed.

https://www.holy-bhagavad-gita.org/chapter/2/verse/23

https://www.holy-bhagavad-gita.org/chapter/2/verse/24

So the premise you have proposed is not sufficient to support your argument.

0

It would seem you've retold me a legend. Something along the lines of "should have known there were no such things as souls because of brain damage". The evidence is real, and should be counted against souls.

But it's not very strong evidence. I will proceed by analogy. When you have a glass tube containing a noble gas, and bare metal plates, you can get an electric current across the plates that is carried by the gas in the tube. As you remove gas from the tube, the current drops, which is evidence the current is carried by the gas. However, when the amount of gas drops below a certain point, the current rises rapidly with no apparent upper limit. By removing enough gas you changed the nature and the current flows on something else without gas. If you know your physics you can tell me why this works, and that's the point. This is the experiment that proved electrons are real things.

Suppose you had the hypothesis, the soul is dependent upon the brain as long as the brain is alive. (Awhile back I wrote a bunch on default hypotheses; and I can't tell whether or not this should be one; but it does not seem to be an unreasonable initial hypothesis.) Would this evidence shake your position that souls exist. Absolutely not.

If you're willing to sift through the trash of people making stuff up for attention, you can find real stories exhibiting the kind of thing where awareness returned to a person with a sufficiently degenerate brain state so that we may be reasonably certain the brain is not carrying awareness. I will tell you the filter that I have used; verifiable information must be gained by this awareness and proven afterwords. Readers Digest did an article on this stuff back in the nineties, and others I have found as well. Yes this exactly mirrors the current carried across the plates.

Here we sit at the unusual place. There isn't sufficient scientific evidence one way or the other and the existing evidence is weak evidence against souls; but the recent historical observations totally separated from religion have weak evidence in favor of souls. It ought to be testable directly; we have the means to test it but I dare not run this test. It is dangerous. All of the cases involved somebody pulled back from the brink of death by medical ability.

3
  • 1
    Vacuum tubes turned out to be very useful, and didn't put people's lives at risk (except for the ones that generate X-rays).
    – Scott Rowe
    Commented Apr 15 at 19:20
  • @ScottRowe: But pushing people to the point of death to observe the soul begin to operate in the absence of a functioning brain is putting people's lives at risk.
    – Joshua
    Commented Apr 15 at 19:21
  • 1
    Right. We should stick to electronics and stop worrying about souls.
    – Scott Rowe
    Commented Apr 15 at 19:23
0

Blessed is he that hath a soul;
Blessed is he that hath none;
But woe and sorrow to him that hath in himself its conception

Gurdjieff — Beelzebub's tales to his grandson

In other words, it's not a binary: immaterial, eternal essence or no such thing.

It could also be that soul is like a talent — like some can have a mathematical proclivity which can be developed into a consummate mathematician; or a musical talent that can be made into a musician, likewise some people may have "soul-possibility" that can be "grown" into an eternal soul.

While Gurdjieff may seem too fringe for these circles, it's important to realize that even "old Christianity" was closer to this than post Cartesian strong duality. See psyche → pneuma.

Note how much more physicalish pneuma (gas-air-breath) is than "soul"

Likewise in Hinduism there's the gross body, subtle body, causal body, atma which is a sequence that can be pealed off one by one onion like.

3
  • So what's in the middle of the onion? "We could have told him he would only be disappointed."
    – Scott Rowe
    Commented Apr 19 at 12:35
  • 1
    @ScottRowe you can join Hindu n Buddhist to say center of atma is anatma (anatta) — nothingness, shunya
    – Rushi
    Commented Apr 19 at 14:07
  • 1
    Chogyam Trungpa called the collapse of ego, "the ultimate and final disappointment."
    – Scott Rowe
    Commented Apr 19 at 14:33
0

Evidence for a soul existing = 0

How much evidence can be needed to refute zero?


If at some future date, evidence for a soul existing becomes > 0...

... then it could make sense to start looking for evidence against. To counter the evidence for.


A good rule of thumb... no evidence for = no need for evidence against.

2
  • 1
    So I guess the real question is, why do so many people feel it exists when there is really no evidence? It must be a sort of mirage.
    – Scott Rowe
    Commented Apr 19 at 2:34
  • @ScottRowe Genetic predisposition. Underlying code that works very well. Creates larger populations. And with life, that's almost always a winning programming. If "we" aren't taking your question as rhetorical. Sorry if we were. Evidence available upon request. Commented Apr 19 at 6:53
-1

Alzheimer's disease kills off neurons

is NOT correct.

"The process of the dying of neurons" is called Alzheimer's disease.

A disease is not a thing, it's just a description of a process.

What prevents us for assuming that Alzheimer's disease is the symptom of a soul unable, or unwilling to live in this world, because of its disassociation with its initial goals, or for other reasons?

4
  • 2
    Find people who, as best we can tell, wanted to still be in the world, but got Alzheimer's anyway?
    – Scott Rowe
    Commented Apr 15 at 17:05
  • 1
    @Scott Rowe, and tell them that this is an indication of not having a soul ? Are you kidding me? Commented Apr 15 at 17:12
  • 2
    I downvoted - I think this answer could be improved by (a) a more realistic approach to language (a disease is certainly not a description, and a process is, in English, a thing: voting, cleaning, dying..., when in fact you clearly understand the OP's point) and (b) by offering some, any, meaningful analysis of, or evidence for, the idea that operations of a soul could be a useful explanation for the brain changes observed in Alzheimer's.
    – Spike0xff
    Commented Apr 15 at 17:40
  • 3
    You'd rather tell them it is a symptom that they didn't really want to be here?
    – Scott Rowe
    Commented Apr 15 at 18:01
-1

Software and hardware can have different levels of dependency. ​But they are almost never independent.

I like the expression: "A small hole in the body can make a gaping hole in the soul."

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .