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Dualism is wholly wrong. There is no mind-body split. Even speaking of 'the brain' is just a rough convenience. Individual neurons stretch from that tangled mass of them up in your skull all the way down your spine and to the soles of your feet. Every nerve fiber extends from nearly every point in your body right into your brain. Perception pours in from every point, and it is all extremely important. Emotion, for instance, primarily arises from biofeedback. Remove the feedback of feeling your 'expression' of emotion and you will cease to be capable of 'feeling' that emotion.
Consciousness is not a 'thing', it is a property. Thus far we know of only one sort of system that can hold the property (human beings in our environment) although we do gain some information from observing humans of different configurations (such as seeing that people with total facial paralysis experience significant emotional dulling and substantial changes to their subjective personal experience over time) that hints at what things are important for different aspects. So far as we have evidence for, there is no reason to think that you might be able to, for instance, simulate solely a brain and have anything akin to consciousness. Just removing patterned sensory input from a typical person via sensory deprivation quickly results in their consciousness dissolving. So how a brain without a body and without an environment to perceive might ever have a hope of consciousness I've no idea.
> Just removing patterned sensory input from a typical person via sensory deprivation quickly results in their consciousness dissolving.
Do you have any basis for this statement?
> Consciousness is not a 'thing', it is a property.
But if consciousness is only a property that doesn't influence the actual physics, then how are we even able to talk about consciousness? Why would it occur to physical beings that something like consciousness exists?
> Dualism is wholly wrong.
What do you mean by "dualism"? Substance dualism, property dualism, predicate dualism, hylemorphic dualism, etc?
Also, you speak as if dualism and some form of materialism or physicalism (there are many) are the only options available to us. What about idealism? Or neutral monism?
I would point out that metaphysically speaking, we have no way of knowing if we are in a simulator. For all we know, the universe could be just the matrix. However it is self evident that our conscious thoughts and experiences exist. This indicates that there is a clear conceptual distinction between our consciousness and the material world in which it resides.
Consciousness is an incredible thing. Reducing it to a mere property is akin to pretending it doesn’t exist at all.
> Just removing patterned sensory input from a typical person via sensory deprivation quickly results in their consciousness dissolving.
What about people born with out sight or hearing or both. Do those individuals not have a conscious?
Here's a thought experiment.
Say you had more than one RNN trained for the same task (say, generating text). How would you couple them?
You could just, character by character, have each RNN generate its output on its own, and then take a majority vote or do some weighted average to combine the output, but otherwise let each RNN operate independently. But wouldn't it be strange for those RNNs whose output was not ultimately selected to continue processing along the same lines, uncorrected by what was actually selected?
Another possibility is to include a "ultimately selected" input to each RNN so they can be privy to the group's decisions. Yes, your internal state said that "e" should be selected, but the group selected "r"- what will you do now?
Yet another possibility would be to perform "retroactive justification". Let us say that one RNN (with an internal state S) selected "e", but the group selected "r". Under retroactive justification, the state used for the next character is a state (maybe the one closest to S) that would have instead produced "r" as output.
Split brains are coupled by their shared access to the body and act within the same environment. How do the hemispheres use that coupling?
Unlike the metaphor you suggest, in the body decisions are not made by vote. Each half the brain controls particular pieces, with the other not participating. A closer metaphor would be separate RNN which each determine one bit of the response, with the response being observed by each.
>How does a brain, consisting of many modules, create just one person?
The same way a population, consisting of many people, creates just one state? The state is not the people and the people are not the state, yet both exist.
I am not my neurons, my neurons are not me, but my identity is driven by those neurons.
Exactly... a non-mystery. But a great example of "the whole being greater than the sum of its parts".
I think Daniel Dennett said it best: Not a single one of the cells that compose you knows who you are, or cares.
> The state is not the people and the people are not the state, yet both exist.
A state does not exist in any physical form. It is entirely a fiction, existing only in the minds of humans. Such existence it does have is not independent of the problem of consciousness so this is not the most helpful comparison.
How so? The state's physical form is comprised of people the way our minds' physical forms are comprised of neurons.
But a state isn't conscious
By what metric do you make that declaration? I submit that any empirical model of consciousness applies equally to states as it does to human minds.
State is the wrong entity here. A population tends to create a culture, and a culture's interplay of ideas runs on its human network. Which is not to say that a culture is conscious either, and in all likelihood if it does have a kind of consciousness it's one that we will not be able to understand.
See Eric Schwitzgebel, "If Materialism Is True, the United States Is Probably Conscious", http://faculty.ucr.edu/~eschwitz/SchwitzAbs/USAconscious.htm
Sure it is. A State reacts to its environment, acts in its interest, engages in rational decision making (at times), and generally exhibits self-aware behavior.
> But without the corpus callosum the hemispheres have virtually no means of exchanging information
They can communicate physically though. Each half of the brain can access the eyes and control various parts of the body, they could make the body do things that they could see/hear in order to act as a basic messaging channel. The conscious part of the brain could be completely oblivious to these subtle physical channels.
I am completely ignorant of anatomy, but isn't the 'brain' still 'joined' at the spinal column? Could communication be going on in there?
Not sure what would be the evolutionary purpose of that. I doubt that many of our ancestors survived brain split and managed to reproduce in order to pass the genes, so having that feature would probably mean it's necessary for something else... sounds like a long shot for me though.
I think what is being suggested is not that it is a special function that only occurs in the case of the corpus callosum being split, but that these other communication channels are always operating regardless and the corpus callosum is specialized channel for certain kinds of information. Speculating based on the article, one would suspect that it allows for fast integration of visual information, but that other integrations rely on other, probably slower, channels.
It's also well known that when one part of the brain dies, other parts will step up to assume its responsibilities. So it's not inconceivable that there is some flexibility there.
Is he saying that the papers/experiments of Sperry (for which he won the Nobel Prize) were not reproducible? They only tested two new patients. How rare are split-brain patients? (I assume very rare indeed if they could only find two subjects).
I imagine the neurosurgeons doing it to reduce epilepsy also want to preserve as much connectivity as possible, so total severance of the tissue between the hemispheres may be rarer in present population of splitbrain patients as their technique improved?
Fascinating subject. Much more is address in Iain Mc Gilchrist's book
"The Master and his Emissary : the divided brain and the making of the western world"
ps: put short, the book explains how pop psychology belief that left is maths and right is arts (you get the idea), was wrong, and yet.. there is a physiologically noticable difference as well as observable differences in how each hemispheres processes reality. In short, each hemisphere attends to the world with a different kind of attention, left is narrow and focused for what we commonly see as intellectual acvitivites, left deals with a map of the world. Right hemispheres takes the world as one whole, it's broad attention required to survive in our environment, but it's also necessary for empathy, etc. The book then tries to show how the over relianceo n our left hemisphere in today's world has roots in the last few centuries, and that perhaps it is not in our best interest. BOTH hemispheres are always needed, but we are increasingly acting in the world from the left hemisphere (hence the book title "the master and his emissary").
Video illustration of the previous experiments mentioned in the article:
> the current understanding seems to only deepen the mystery of consciousness
Not sure I understand that.
What they appear to have established is that, if you sever the direct connection between the two brain halves, functions that required the direct communication between the two halves is impaired.
I mean, it's interesting to note what those functions are and the severity of the impairment. But there doesn't appear to be any effect on consciousness at all; at least not in the article's description of the effects. Am I missing something?
I think that's the point. The previous work referenced in the article seemed to indicate something much MUCH more profound.
Conversely, when you combine two brains, do you "merge" the people?
This is part of the philosophical problem of identity. Is there a non-physical part of the mind? If you duplicate a body by cloning, matter relicator, or exact uploading into a computer, do you have multiple persons or souls? (Star Trek explored several variations) Does [any part of] the mind survive death?
The thing that has stuck with me is the career test that was given to someone with a split brain, and one side wanted to be a racecar driver and the other wanted to be something completely different. [1]
[1] https://www.psychologytoday.com/blog/the-superhuman-mind/201...
There is a video about a split brain patient (somewhere), while they are shopping.
The left hand might put a box of cereal into the shopping cart, but the right hand puts it right back on the shelf. I wish I cod find the video.
> The brain is perhaps the most complex machine in the Universe.
That's when I found how useful a 'perhaps' can be. LOL.
> The brain is perhaps the most complex machine in the Universe
Do you really know what's there in the entire universe?
No, hence "perhaps". The meaning and intent of the sentence is entirely clear so I don't really see what good this sort of pedantry does.
What do we know of the world and the universe about us? Our means of receiving impressions are absurdly few, and our notions of surrounding objects infinitely narrow. We see things only as we are constructed to see them, and can gain no idea of their absolute nature. With five feeble senses we pretend to comprehend the boundlessly complex cosmos, yet other beings with wider, stronger, or different range of senses might not only see very differently the things we see, but might see and study whole worlds of matter, energy, and life which lie close at hand yet can never be detected with the senses we have.
Yeah, I just checked. It's definitely the most complex. Well, other than the thing in Nebula VOQ 34E, but that's a given.
'perhaps'
Probably not, hence perhaps.
Known
Weasel words allowed them to escalate to "Universe".