Tnanks to some insomnia, I did write some more about consciousness. I have no idea if its of any use.
This is going to sound a bit like Buber or Tillich. While it's not consciously based on either's thought, I did read some of Buber's writings in my younger days, without a great deal of comprehension, true, but it's possible the ideas have been percolating around. And I read gobs of Tillich plagiarized in MLK' s thesis. MLK was pretty faithful to his original sources :-/
OK, what do we mean by consciousness? I would argue it's the feeling of personhood, of the 'I', that we have, which transcends thought or perception or volition. If you've ever been extremely drunk, or delirious due to disease, or under the influence of other psychotropic agents, you've undoubtedly experienced conscious states where thought or perception or volition were severely compromized. Nothelessless, there's always a feeling of 'I' ness in there, something in the center that knows you're drunk or deranged and is basically unaffected. And when you dream, although even ordinary logic is twisted, there's an 'I' there. That's what I would call consciousness.
We don't have any direct experience of anyone else's consciousness, but we mostly make the suppostion that someone else who looks and acts like us also has this kernel of consciousness. I say mostly because i understand sociopaths don't do this. I would argue that when we're very close to someone, we can in effect use part of our own consciousness to form a mental model of theirs; if our model is a good one; if it's based on observation of the other rather than our own ego, then to some extent it's detached from us, and it gives us a feeling of empathy, or agape, or whatever - a selfless and direct perception of the other within ourselves.
While none of this is scientific, I'd argue it's the best we can do to overcome the problem of solipsism; that we each on our own have a very limited sampling of 'consciousness' - our own - and without empathy have nothing to compare it with, so the usual means we use to figure out what something is are almost useless.
OK, where I'm going is this? If we're going to study consciousness; clearly it has to start with the brain, because that seems to be where it resides. And, to be crude, some of the best experimental data we have on brain function comes from brain damage. A lot of this is very basic - Luria, the great Soviet neurosurgeon, had a massive database of brain-injured Russian soldiers, and was able to correlate various forms of dysfunction with particular injuries. Trouble is, I don't think he had the inclination or the freedom to go asking metaphysical questions, though he may have reported phenomena which might be useful to you in some of his voluminous writings.
I don't know if you've ever had to deal with someone very close to you who developed dementia. I've unfortunately had to do this twice. One of the more horrible things about it is when the dementia has progressed significantly, and the loved one's motor control, cognition, memory and awareness of the world around them seems to be mostly gone, occasionally there are flashes where they seem to realize who they are, but can't figure out what's happening to them, and are scared. I think one has got to be close to the person to see this, but I'd argue it's real, and not merely an illusion. When someone is far gone, there's a natural tendency to look for hopeful signs the person we love is still 'in there', and that's likely to be misleading; but no one goes looking for horror in a loved one's eyes. No one has to my knowledge been able to write what it's like to be in severe Alzheimers, and so we can't easily tell if there's consciousness at that level of brain injury, but I'm sure from my own experience (or empathy, though with the caveat my wife tells me I'm the least empathetic person she's ever met) that the person retains personhood or consciousness into fairly severe brain damage.
So where does this lead? If consciousness can survive some fairly major brain damage, it's no delicate interplay of thousands of neural signals. I don't know, and haven't researched, whether there are regions of the brain whose loss seems to diminish a persons' humanity or consciousness, but I wouldn't be at all surprised if there were clues buried in dry clinical language in the medical literature. On the other hand, maybe it's a function of the entirity and not of one of the parts. But I am sure, if you want to find it, the brain is where you have to go looking.
RWP, my heart goes out to you, as to one who has witnessed the devastation of Alzheimers in persons close to you. You have felt their horror (experienced in relatively rare moments of partial lucidity) as your own. In a certain way, that seems to open up a wider sphere for consciousness than perhaps we are accustomed to assume -- a meaning of consciousness in the sense of something that can be shared, as verified by strong emotional reactions (how I hate to use that word in this context) rooted in compassion and love.*
There is no "language" to express this sort of thing in the sciences today. And yet experiences like this are so much a part of human existence, of what it means to be human.
I really need some time to think through the issues you raise, which are inspirational for me. It might take me a while, and I'll probably post whatever I come up with as a separate thread, in due course. I'll ping you when the time comes.
Thank you so much, Professor, for writing.
Jean
*I've recently read about experiments conducted in regard to "induction effects" of consciousness, which suggest that there's more to consciousness than the sense of discrete self.
There certainly are. in the 40's or so psychologists were trying to cure crazyness by lobotomies. This failed to do anything. Nowadays they are trying to cure epilepsy the same way, failing again. There are also examples from people who have brain operations for cancer. The brain does heal itself.