Friday, November 21, 2008

Still Think You've Got an Immortal Soul? You Need a New Brain

I’ve argued in a number of contexts against the immortality of the soul. Whatever a soul is in the popular imagination, it seems essentially to have your personal properties of memories, beliefs, desires, self-awareness, and consciousness. That is, your soul is you. The problem, of course, is that all of these features of you depend upon the function of your brain to exist. Disrupt the brain enough with drugs or abuse, damage it with trauma or a stroke, or destroy it, and all of stuff that makes up your mind will stop. This is not a particularly new or creative idea. It’s become a simple, obvious truth throughout the neurosciences and even in philosophy of mind. While many philosophers hold out, insisting that there is something magically irreducible about qualia, beliefs, intentions, or what have you, they will almost all concede that even if the mental cannot be readily reduced or eliminated into the physical, the mental depends upon the physical. We have no plausible evidence in favor of the view that a mind could exist without a brain. But we have mountains of evidence that the mind is utterly dependent for it features on the existence of the brain. This much is widely accepted even though there are a wide range of views about how best to theoretically describe the mind.

In case you didn’t notice, I’m equating the soul with the mind. I won’t apologize for that. That’s the widespread practice too, at least among people who are willing to talk seriously about souls. And I can’t make any sense of any accounts of the soul that I have heard that try to tease out a difference between it and what we traditionally identify as the mind.

In three lines, here’s the argument:

1. Everything that we attribute to the soul depends upon the brain to exist.
2. At death (or soon thereafter), the brain ceases to exist.
3. Therefore, at death the soul ceases to exist.

The action is all in the first premise, of course. I take it that your own experience of what a triple espresso does to your thoughts, LSD, brain damage, strokes, and evidence from the animal world make premise 1 obviously true.

Sometimes people will resist, arguing that the evidence from neuroscience, car wrecks, hallucinogenic drugs, and monkey studies is all consistent with viewing the mind as a sort of remote pilot. The soul, they say, isn’t really dependent for its existence on the brain. Rather, a functioning brain acts as a sort of control nexus through which the ontologically separate mind exerts influence on the physical world. When you damage or alter the brain, you’re not actually compromising the mind itself. You’re really just inhibiting or damaging the control panel that interacts between mind and body. If something like that were true, then you’d expect to see people’s ability to act, talk, and express themselves compromised by brain alteration. But that’s at least consistent with the mind’s being completely fine.

This is a modern sort of dualism, you’ll notice. And one set of responses to this view has to be the same objections that are always given to Cartesian substance dualism: how does a physical thing interact with a non-physical thing? how can a mind that has no spatial location connect to a brain that has spatial location? And so on. I won’t pursue those worn classic objections here.

But here’s a problem to consider. If you think that your soul is a separate or separable entity from your brain, if you think that your soul doesn’t essentially depend for its very existence on the normal functioning of your nervous system, then you should be willing to engage in an experiment with us. Suppose that we had the technology to do a brain transplant on a human being. If you think your soul is some magical, mystical entity that floats free of the natural world, then you should be willing to undergo a brain transplant. It should be ok with you to have your current brain taken out, tossed in the disposal, and then have another one stuck into your skull. Since your mind’s functions don’t depend upon brain configuration or operations, then it really shouldn’t matter which one we put in there. The new brain shouldn’t change your thoughts, your desires, your self-awareness, or your memories since those are all safely part of your soul.

So how about it? Are you willing to undergo a brain transplant and let us toss your old one into the rubbish? Honestly, if you’re still clinging to this medieval nonsense about souls leaving the body, then your brain is due for an upgrade.

18 comments:

rc said...

Interesting post Matt. I was just recently reading a similar argument on the infidels website.

rc said...

Concerning this statement Matt "If something like that were true, then you’d expect to see people’s ability to act, talk, and express themselves compromised by brain alteration. But that’s at least consistent with the mind’s being completely fine." could you please clarify or expound upon.

Thanks Matt.

Bryan Goodrich said...

I got a possible response to your challenge. It hinges on what the soul attaches to. Since the brain acts as the conduit by which the soul "drives" this meat bag, and you basically ejected the cockpit, the pilot is no longer there. The soul is no longer attached to that body, and wherever you got the brain from, you basically implanted another soul.

We might also throw in that the soul is attached to the brain. Without that physical attachment, it simply goes to wherever souls go to (heaven?!). Unless one is willing to assert the soul can just pick up and leave the body, and jump into another one, then it is attached to its point of interaction (the brain). So pulling a brain out of one person is basically transferring one pilot to another ship while ejecting the old and letting him to go heaven, or wherever.

Of course, this implies that the meat bag left over without a brain attached (or functioning?) is soulless and we can do whatever we want with it. The dualist might argue, though, that the brain activity is driven by the soul and it might be able to come back as long as everything stays the same and we have no justification to destroy or mess with the soul's "property." Of course, even if we might accept the first dualist response, this second one is clearly ad hoc to the nth degree. It also requires that the soul be attached to its cockpit. If you make it attached to the whole thing, then you obviously will run into conflicts.

We might say the soul, though, is "spread out" so that it is everywhere. When throwing out the brain, as described above, we threw out the control features of the soul, but the "moral" properties of the soul still existing there remain. We also get a blend of souls when you put another brain in there, but since nothing is centralized, it's like switching out one server among many on a network. You still have the network just the same, maybe just with one better making it overall improved.

This still begs the question about what the soul is and the properties surrounding it, and how that has anything to do with the real world. The problem is we usually think of the soul as something centralized and not decentralized across a system. Decentralization will actually work more in favor because you can still get the fact that you can replace part of the soul and still remain having the same "soul-person," at least in the respect that the body is still "Fred" say, and the brain transplant turned the self-identity into "Joe." To use the computer analogy, say the network you interact with is named by one server. The network remains, even if now the server switched out was once Fred and is now named Joe and responds accordingly. The other properties of the network remain. This is, to a large extent, how the human body works. The "network" just happens to be the biochemistry of all the component parts and systems. The problem this dualist response faces is the fact it is absolutely no different than the reality! It still begs the question as to what the soul is and what role it plays. It appears epiphenomenal and a worthless concept.

Matt McCormick said...

That's all interesting, Bryan. But as with lots of the responses that people engineer to problems with God beliefs, its an answer that can only answer the original problem by introducing even more bizarre new puzzles. (As you point out). As such, I'm not inclined to take it very seriously or expend much energy trying to answer it--although it's a noble effort of you to bring it up. Before I would try to explain the problems embedded in this silliness, I'd want to see some good reasons for thinking that such a thing as a separate brainless soul even exists. It's not enough for believers to merely posit that such a thing is possible. They need to have some real reasons to think it's true. And I can't say I've every heard anything very interesting along those lines. People seem to believe it, but short of faith or an appeal to the Bible, they don't seem to be able to say much about why it's true. But I doubt that you disagree with any of that. Thanks for your post.

MM

M. Tully said...

Bryan,

You wrote, "It still begs the question as to what the soul is and what role it plays."

But, what evidence do you have that a "soul" even exists?

Consciousness without a material brain has NEVER been demonstrated.

I see no difference between your statement and, "It still begs the question as to what unicorns are and what role do they play."

Bryan Goodrich said...

Tully,

You say, "But, what evidence do you have that a "soul" even exists?"

That was the entire point behind "it still begs the question..." I wasn't providing an answer about the soul. My challenge was to articulate a dualist response presupposing dualism is correct. Matt's argument challenged dualists that given their beliefs, consider the scenario and see the absurdity that arises. I don't think it completely leads them to a contradictory; though, it clearly puts them into a position where they have to define the soul, whatever it is, within a certain scope that (1) makes it appear rather strange, and (2) become completely unattainable epistemically if not be completely useless (epiphenominal).

If anyone wants to argue for the existence of the soul or dualism, I'm all ears. I have always found dualism to be down right stupid. In the end, you'll never get a straight answer as to what the soul actually is.

Matthew A said...

Hey Matt,

2. At death (or soon thereafter), the brain ceases to exist.

This seems to me to be a strange claim. Perhaps you should say that the brain ceases to function upon death? If I die of a heart attack my brain still survives my death. I understand the need to eliminate the brain considering the your insistence that brain=soul and if the brain remains so too the soul. Perhaps it's just enough to say that soul=brain and that if the brain dies so does the soul.

Also it seems that your argument is aimed at survival of death. Your argument does not however pose a threat to a materialist concept of the resurrection and self (one in the manner that Inwagen has written about).

Anonymous said...

"If I die of a heart attack my brain still survives my death. I understand the need to eliminate the brain considering the your insistence that brain=soul and if the brain remains so too the soul."

Huh? I do autopsies for a living. After you die, the cells die - some later than others, but you can see their evolving death under the microscope if not in your gloved hands.

Matt A said...

What I meant by that was that the physical mass that is the brain continues to exist after death.

Matt McCormick said...

I don't think there's anything worth quibbling about here. Matt A, I think you take my meaning. If you take an old car to the scrapyard and dismantle it and melt the metal down for new steel, someone might insist that in some very loose sense the car still exists because the matter--the carbon, the nitrogen, and so on--hasn't been destroyed.

The point at which all electrical and chemical activity in the neurons of the brain ceases is not the same point, typically, when the heart stops. Doctors don't consider clinical death to be merely when the heart stops anyway. They have a rigorous set of criteria that need to be met before they declare clinical death. But some electrical and chemical activity continues in the brain long after that, I suspect, in lots of cases. So death is a much fuzzier matter than one might think. But none of that really matters for my argument. Once the brain is far enough gone, it doesn't think. And if you leave it there long enough, languishing in the grave, then it decomposes to the point that no reasonable person would deny that what was once the brain is now gone.

I haven't argued for the impossibility of any form of survival. If minds depend upon brains to do what they do, then as long as you have a brain of a certain sort, then you're good to go. If Christians want to argue that God will regather the materials, long rotted away in the grave, and then rebuild your brain, then I'd love to hear that argument. And what we need to hear is not just an argument for the possibility of such silliness, but some actual reasons to think that such a thing will ever happen. This argument concedes my point that minds require brains and the conclusion that no brain means no mind.

For a fuller discussion of all of the details here, see my paper:

Against the Immortality of the Soul, published in Death and Anti-Death.

M. Tully said...

Bryan,

Apologies. I realized what you were doing but I certainly didn't make that clear in my reply.

I was presenting my answer to dualists when that argument is made.

Anonymous said...

Dude, you're a fag.

Anonymous said...

"2. At death (or soon thereafter), the brain ceases to exist."

Do you mean ceases to function? or do you really mean exist?

"Honestly, if you’re still clinging to this medieval nonsense about souls leaving the body, then your brain is due for an upgrade."

Please get right on developing brain upgrade technology. That would be so sweet. Maybe instead of 12 boring years of school, then college, you could just have a synthetic or cloned brain installed with everything you need to know already in there.

kk said...

What is the goal of quibbling about ANY of this? Life is a breath - why bother attempting to decipher our existence or modify the beliefs of others? If people wish to believe in a soul that exists independent of physical body, let them.
Why waste a moment pursuing any degree of truth if our mind/soul will ultimately rot in the grave?
Instead of all this intellectual posturing, enjoy some Jack Daniels, try a new restaurant, go skydiving, plan another tropical getaway, rent a weekend full of movies... bide your time until the inevitable.
Eat, drink and be merry, for tomorrow we die.

Stephen said...

If by some strange event all of your memories were gone, your history, desires, beliefs, self immage all gone. The brain still functioned in that awareness still happened, though nothing had a name or a use you would still notice things feelings and so on. Would you still be you to yourself? Would you still have the feeling "I am.' even without words to describe the feeling?

By some strange happening beyond my mental powers i came to exist out of nothingness into a physical form with self awareness, the i am. IS it so hard to expect that this may happen again?

We can talk about a wave on the ocean, its size, its shape its speed and so on. A wave is born grows, interacts with other waves and eventually dies. Mind is like the wave, it has form is born and dies. Soul or awareness as I prefer is the ocean.

Analogies are poor substitutes for the experience. You can talk about strawberries all day long but unless you taste one you don't know strawberry and after you taste one no words are needed.

Stephen said...

If by some strange event all of your memories were gone, your history, desires, beliefs, self immage all gone. The brain still functioned in that awareness still happened, though nothing had a name or a use you would still notice things feelings and so on. Would you still be you to yourself? Would you still have the feeling "I am.' even without words to describe the feeling?

By some strange happening beyond my mental powers i came to exist out of nothingness into a physical form with self awareness, the i am. IS it so hard to expect that this may happen again?

We can talk about a wave on the ocean, its size, its shape its speed and so on. A wave is born grows, interacts with other waves and eventually dies. Mind is like the wave, it has form is born and dies. Soul or awareness as I prefer is the ocean.

Analogies are poor substitutes for the experience. You can talk about strawberries all day long but unless you taste one you don't know strawberry and after you taste one no words are needed.

thebrainmartians said...

The idea that the soul is transient, and departs the body for other locales upon ones death (be the destination another body, heaven, etc.) is certainly within the 'popular imagination' in regards to the definition of the soul.

So, while that is not directly stated as a premise, it is one, albeit one you have chosen to gloss over to further your argument, despite the fact that you yourself appeal to the 'popular imagination' to get your argument rolling.

#1 - Everything that we attribute to the Soul depends upon the Brain to Exist.

This premise is simply not true. Again, it is widely accepted that the soul is transient, and the souls transience is in no way tied to the brain.

Having caught the tongue-in-cheek humor in the title of your post (it took me a few minutes to catch it), I can see now that it is more of an attempt at humor, than the presentation of a well thought out argument for the mortality of, or denial of the soul.

I look forward to reading some of your other threads.

esset said...

If we do not have souls ,how would you explain cousciousness.