Anil Seth's Being You is a recent one that does a good job of summarizing the most popular theories in consciousness. https://www.goodreads.com/book/show/53036979-being-you
The Routledge Handbook of Consciousness (https://www.amazon.com/Routledge-Handbook-Consciousness-Hand...) is far more comprehensive and while being more academicky is still an excellent read.
Unfortunately both miss what I think is easily the best and most computationally robust and fleshed out consciousness theory, but that's because it's so tragically unknown. I co-authored a book that covers this (while staying accessible) https://www.goodreads.com/book/show/58085266-journey-of-the-...
So much of the stuff in the mathematical-this and physics-that of conscious experience is just crap because there is very little understanding of biological consciousness and what it is and where we can find it, and where we cannot. These start with assumptions of what consciousness is and then go on to mathematize these non-validated assumptions. (Integrated Information Theory) IIT is the most popular among these. https://scottaaronson.blog/?p=1799 -- this article captures well why IIT, and many like it, are bad models of consciousness.
I am a software engineer by profession, but this is a topic that has been on the back of my mind for many years. Even when I read popsci books about the universe and the big bang and so on, i felt spiritually unsatisfied because they often do not address this elephant in the room - consciousness. A theory of everything that explains the laws of universe will be imo incomplete if it doesn't also explain, at the fundamental level, the laws of the universe that exists behind our eyes. It really deserves more attention and awareness among geeks and the general public.
But I agree with your assertion.
Galileo’s Error, published in 2019, by Phillip Goff traces the history of the mind-body problem and illustrates how we divorced our consciousness from the physical world during the development of early modern science and philosophy.
Last century, Ernst Mach and Bertrand Russell argued in favour for neutral monism, a stance which holds that the mental and physical are two sides of the same coin. It seems like these ideas are coming back after a long stretch of dogmatic physicalism.
Panpsychism gets a bad rep for sounding like it has associations with vacuous or flimsy New Age beliefs, but it means a totally different thing in the context of philosophy of mind and consciousness studies. It is the claim that consciousness might be a building block of the universe.
The main problem with panpsychism is not that it is incredulous, but that it currently lacks a compelling explanation for our individual subjectivity. If consciousness and mental properties are ubiquitous in the universe, why do I have my consciousness and you have yours? The main motivation to believe in panpsychism seems to be its incredible elegance and self-consistency. That alone does not make it true, but it might be a very big hint on where to look for answers.
> It really deserves more attention and awareness among geeks and the general public.
There's 0 interest in consciousness because it's so hard to pay attention and realize that it exists. We go about our days for weeks, months, years and even decades without even noticing that consciousness is a thing.
Do we? I feel like I'm constantly reflecting on it and trying to make sense of it, and that I'm certainly not alone. I'd like to think that it's part of being human to turn the lens back on itself and wonder "what am I?" But I suppose some people could care less for navel gazing.
When really, humans give themselves (their own thoughts) way too much credit and most are barely aware of their own thoughts, barely self-aware at all.
It is easy to say something is ‘un-explainable’ and thus ‘must be in some otherworldly realm that is beyond comprehension’, if one is not able to observer the problem. Most humans aren’t self-aware enough to know their own thoughts or examine where those thoughts come from.
Just a few decades ago simple voice recognition was deemed ‘a totally human ability that the computer will never accomplish’, now it is ordinary.
It comes down to humans internal subjective reality is both amazing and ‘unknowable to the outside’, ’un-observable’, thus un-testable. But then we make this giant leap that nothing we will ever build will also have some ‘internal subjective reality’.
It keeps coming up that GPT is a glorified auto-complete, but then never explain how a human isn’t also just an ‘auto-complete’ machine, just going through the day twitching at stimuli. Why do we think a human doing copy/paste, and regurgitating something they heard, is special, but if a computer does then suddenly it is completely invalid to think they could ever be conscious.
However, OP was referring to the hard problem of consciousness. The hard problem of consciousness is unsolvable IMHO by science, as it is entirely subjective; in fact, it is the fact of existence of subjective experience. The problem is this: even if you find some objective mechanism that generates consciousness, how would you make the explanatory leap from the objective mechanism to the subjective? Even if you say: "Oh, we flipped this switch and now this person is unconscious." - this is a description from the outside. You cannot claim by this that the person's consciousness has disappeared. Maybe not connected to the contents of the human mind anymore; but the gulf between objective and subjective can never be crossed by objective science.
If I had a dollar for every time someone claimed that the hard problem of consciousness isn't actually hard, I would be very rich.
There is only 1 consciousness. Soft is describing how it can be done physically, how to build it, or explain it, and hard is what it is like to experience it from the inside.
By creating the hard problem, it really just says "we can't know anything about any internal state". All "internal subject states" are self reported, and a machine can just as well self report enough to mimic a human. So at that point, we can't prove that the machine doesn't have a 'subjective' internal state.
By this line of reasoning, we can't prove that any humans are conscious either. Any lines of logic that try to prove the hard problem, would either both prove that the machine and human are both conscious, or prove that neither are conscious.
The hard problem is not stating "we can't know anything about any internal state", it is about the mere subjective existence of the internal state and not about the contents of internal experience or any objective fact about that internal state. I don't know why this is seems often so hard, but in consciousness research and meditators' language (or in my native language at least), most of this seems pretty well-definded.
It has no relation to proving that humans or machines are conscious. It is about no objective fact at all, and thus cannot be investigated using objective methods. That is why it is unsolvable by objective science.
To use a koan-like: It is about this.
I would say that this examination of the problem of our internal view of the world, versus the reality of the world, subject versus object, goes back thousands of years.
I've also meditated a long time, and I do understand the hard problem. I just don't think eastern philosophies have the answer either. Eastern philosophies definitely had a jump start on the West with examining the mind, and really it was Buddhism that informed western philosophies from Schopenhauer onward. They helped defining some vocabulary and hierarchies, like outlining Skanda's or parts.
BUT, the typical eastern answer, that it is just 'this" and other 'wooo-wooo' answers are just as far from any explanation to the 'hard' problem as anybody in the west has. Meditation can get you awareness of the hard problem, some insight, but it still isn't an explanation. It just gets you another perspective that is still "Internal". I can meditate forever, but any 'realization' is still internal to me, it isn't providing any answers or explanation.
This comes up a lot right now with AI getting so human like (recent advancements), and I would say that at some point we'll create something that will be indistinguishable from a human, and at that time if the AI speaks convincingly of their realization of 'this is it', we wont have any ability to disprove that they really have had the same 'wooo-wooo' feelings. There is no way to prove anything.
So what I am speculating here, is that at some time in near future, we will be able to correlate soft and hard problems, so we have a map from one to another. And we'll have to realize that our own internal 'experience of reality' is just our neural net in our brain reacting and processing to stimuli, and we'll be able to examine the same things in silicon. And we'll have to accept that we aren't some super mystical beings or that our 'consciousness' is not all that special a development in the universe.
So lets say in current models', or future, in very large neural nets, that there will not be some internal subjective awareness, just like we have. We've mapped the entire neural network/nervous system, of a nematode worm and translated it into software. The 'software worm' appears to behaves the same as the real worm, so what is that software experiencing?
Actually, there is every indication that you are an illusion.
The fact that we think we can observe and comprehend a mechanism doing the observation does not preclude things we cannot see. You might be able to pan a cctv camera and get some insight about the camera itself if you find a reflection, but you can’t pan it over to the linux driver. It is not a given that all of the observer exists within the observable universe.
It seems short sighted to suggest we can’t find out things about consciousness in a similar way.
We can almost definitely learn a lot more about consciousness related phenomenon than we already know through science, and I don’t know the answer to OP’s question about the current cutting edge of that, but I think it’s always going to be about related phenomenon rather than consciousness itself. Unlike other phenomenon, which are only revealed to us because aspects of their existence appear in our observable universe, we don’t really “observe” the core experience of consciousness. The goalposts can be moved indefinitely whenever consciousness related phenomenon are made sense of. The fundamental experience is not observable, which means we can’t really see that black box at all. To me the mystery of that is much more satisfying than thinking we can ever get a definitive answer.
It is easy (and cognitively useful) to forget that, when the indirection is very reliable.
As far as consciousness, we won’t just have to speculate based on our own consciousness. As artificial minds become highly self-aware (a functional ingredient of consciousness), we will be able to construct very controlled experiments.
There will be endless numbers of experiments we will be able to do once we can edit self-aware entities and both externally query and internally monitor them.
That's what the observability issue is about. Heck, I think you're conscious, but I cannot know for sure.
There is no way to distinguish between an unconscious machine mimicking the functional aspects of consciousness we are able to indirectly observe and compare to our own experience and something having the same experience.
We could easily (and I think almost definitely are given the current pure symbolic manipulation track) be doing the same thing as a jungle cargo cult constructing an air strip out of sticks. Studying that won’t tell us how planes work.
Obviously advanced AI is more sophisticated than that and may have more legitimate parallels to consciousness, but I think it’s fundamentally impossible to know what’s a core part of the conscious experience and what just looks superficially similar to the output of conscious beings.
The current generation of AI are clearly not at all conscious and are “just” (don’t want to diminish the work) very good parrots generating image and text output from a given input in a way a whole bunch of conscious humans already have. But we’re already getting cargo cults and people who are anthropomorphizing and considering them comparable to humans.
There’s a danger in studying artificial models of an underlying phenomenon to learn about the phenomenon. That method of study is inherently very limited and extremely difficult to keep calibrated to the underlying phenomenon.
As noted before, all observations are indirect. That has not been the unique challenge for studying consciousness.
The unique challenge has been an inability to create constructive or destructive experiments.
We didn't know how to construct consciousness candidates or precursors, of varying kinds to study. We are getting close to that (i.e. self-awareness as a functional quality is certainly a precursor.)
And we have not been able to create controlled demolition of an consciousness candidates, due to the morals of human experiments. (But our artificial minds will be alterable and destructible at will, to test hypothesis.)
Our conscious experience is in fact a unique phenomenon because it is all perceivable phenomenon.
You can create as many self reflective machines as you like and experiment on them and compare them to output from humans, and maybe you’ll learn things, but you can’t ever get to looking at consciousness at all. There is no indirect or direct data you can use to compare all of your experience to something that sits inside a fraction of it.
What you’re talking about are behavioral experiments comparing the reported thoughts and actions of separate acknowledged conscious actors, ie other people, to the internal states and outputs of machines.
You’re not looking at consciousness when you do that. Looking at consciousness requires looking at all experience. Which is fundamentally impossible. When you try to look at all of experience as a single object to study nothing is differentiated. There is zero information.
The problem with consciousness is that we have no ability to measure it objectively because it is an entirely subjective phenomenon.
You have no way of knowing if I am conscious or just a sufficiently elaborate machine doing a really great job of acting like I am (a p-zombie).
Personally, I lean towards panpsychism. I assume I am not special and that everything in the universe, or to put it another way the entire universe itself, has an experience of being.
Of course not! Regardless of whether the core phenomenon is fundamentally impossible to explain (which I think it has to be for philosophical reasons), it’s an incredibly productive question to ask/am also curious about cutting edge theories and related findings.
(1) https://plato.stanford.edu/entries/kant-reason/#LimiReas
In fact, you would not even experience the disappearance of consciousness - because the consciousness that would experience this has disappeared. It is impossible to experience the absence of consciousness.
[1]: Gibson, J. J. (1950). The perception of the visual world. Boston: Houghton Mifflin
[2]: Ittelson, W.H. (1973). Environment and Cognition. Seminar Press, New York, NY, 187 pp
[3]: Kosslyn, S. (2005). Mental images and the brain. Cognitive Neuropsychology, 22, 333–347
[4]: Northoff, G. (2004). Philosophy of the brain: The brain problem. Amsterdam: J. Benjamins Pub.
[5]: Dewey, J., & Bentley, A. F. (1949). Knowing and the known. Boston: Beacon PressThis paper is a good, accessible overview of how this would work in neuroscience:
People who like to talk about consciousness have a problem keeping the goalposts in place (and trying to exclude cognition from consciousness, presumably because "cognition" doesn't sound mysterious enough, is a great example of this sort of moving of goalposts).
The truth is consciousness is an emergent phenomenon, and it can only be understood as such. Of course we have a lot more to learn, but we understand the fundamentals of neuroscience and biochemistry, and we know how our conscious experiences emerge from those. A neuroanatomy textbook (eg.: Blumenfeld) is probably the best place to start. There is unfortunately no single "thing" called "consciousness" that we will ever be able to point to.
> Consciousness" is not a thing. It's a collection of things, […]
A collection of things is a thing.
> The truth is consciousness is an emergent phenomenon, […]
I don’t think that is controversial at all.
We have unraveled the workings of many emergent phenomena. Emergent doesn’t mean incomprehensible.
In programmerland, one might say something like "the abstraction you're using is counter-productive", for whatever reason, when looking at some junior hire's code. It's very much the same here: trying to understand consciousness is asking the wrong question. It's like asking "Why is there a God?": it's an unproductive question because it's a question that can't be answered. The abstraction in the question simply doesn't map 1:1 to abstractions in the world in which we live. If we want to understand our world, we'll maximize our odds of success if we focus on studying the abstractions of this world.
I wouldn't describe myself as a pessimist at all, and I'm not sure why you thought my comment was pessimistic... But this opinion of mine (because that's what it is, it's an opinion, not an argument) is a professional opinion. This isn't my field of expertise, but I do have expertise in very adjacent fields.
And a pattern is a thing.
Consciousness is an everyday experience that appears to be reliably shared by billions of entities who communicate about it to each other. And have done so for at least millennia.
To use a colloquialism: It’s a thing
Replace type with concept and value with thing, and we get a rebuttal using the same language. You can also switch the terms, depending on how 'a thing' is interpreted. If you are more familiar with set theory, replace type with proposition, value with element. The critical difference is between reference and referent.
Further if large numbers of people holding something is true for considerable duration is sufficient for something to 'be a thing', we'd also have an argument for 'the consciousness of the human heart' being a thing, which I don't think anyone would argue in good faith these days. There are probably better examples, but note that the duration of time and frequency of experience are parameters with no obvious values indicating at which point the underlying 'thing' should be accepted as undeniably 'a thing'.
The whole point of requiring it to be technically defined is that all this confusion just goes away and it becomes possible to ask more meaningful and less ambiguous questions about it.
That said, I will concede that the argument I have made does not say that consciousness is definitely not 'a thing', just that it is defensible to say that it is not a thing, given that it is held that either it does not represent a proposition, or that the proposition it represents is not true. (note I'm using the term proposition with some handwaving).
The most fundamental aspects of reality, and mathematics, are still not founded completely on formal definitions, without resorting to circular reasoning, and attempts to prove things assuming the things that are being proved.
Existence isn't well defined. Yet Descartes' famous informal claim "I think, therefore I am" is still a compelling statement that each of us can use to verify we do exist. Despite many unanswered questions.
Likewise, "I am aware of myself, my own thoughts, my interactions with a world around me" is a compelling statement supporting consciousness. The fact that we can all verify our own consciousness the same way, and discuss those experiences with each other, makes it even more compelling.
Despite lots of unanswered questions.
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Your counter examples are also weak. Most subjective beliefs about hearts having consciousness are not nearly as credible as informal arguments for existence and consciousness.
Conscious hearts are not virtually universally experienced.
Informal reasoning about why a heart, a blood pumping organ, would correlate with consciousness are not generally accepted informal arguments.
People whose hearts are replaced with artificial or donated organs don't reliably report a loss of consciousness.
My claim is that while tools to determine if consciousness exists do not presently exist, it is possible that they are discovered, and applied, and that the question of the existence of consciousness is open. Note that for me existence is a fundamentally formal notion. I cannot defend this except on grounds of its anecdotal usefulness because it is akin to an axiom or ground truth.
The notion of consciousness I consider is with respect to its 'actual' existence[1]. Suppose I imagine a circle, and then a square, but believe I imagined at once a round square. That I can consider the notion of 'a round square' or may have had a direct perception of it does not require me to accept its existence. Likewise, I do not need to accept the existence of a unifying singular notion of what might be perceived as consciousnesses. This also does not necessitate I reject it. If consciousness cannot find an agreed upon definition, assertions regarding it lack semantic meaning and cannot be 'reasonably' (waves hands) assigned truth values. If an exact definition is determined with no logical contradictions, I defer to the physical sciences for determining its plausibility.
The notion of conscious hearts was more credible in the past. The idea was that before the role of the heart was understood, a large population could have been convinced that 'the heart is the seat of consciousness', and thus a large population believing they were experiencing something a particular way may have been followed by the falsification of the existence of such a thing. At the time, it was very plausible that it was considered impossible to ascertain whether or not there were thinking hearts. I concede that the notion is not presently credible; for my purposes it is sufficient that it was ever credible.
If you regard existence proofs as being extra-logical, it may not be the case we can find agreement since we will be effectively talking in different languages. Personally, I am very skeptical of the ability of the human mind to find truth informally, which is why I lean on formal notions heavily.
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1: My favorite essay on this distinction is Quine's (admittedly polemic) "On What There Is". The distinction I consider is slightly different from his in that I am also expressing distrust of direct self-perceptions of the mind's functions.
Just because someone believes something, doesn't mean there is a compelling argument it exists.
But if something can be studied by many independent people, with strong agreement not based on passed-on beliefs, then there is likely to be something there.
I.e. I am unaware of a universal experience of souls, or informal arguments for souls that are compelling.
I am aware of informal arguments for existence ("I am, therefore I exist") and consciousness ("I experience myself, my own thinking, even this thought itself, so I am conscious of myself"). In both cases, the vast (vast, vast) majority of humans conclude they do exist and are conscious. And the informal reasoning is very strong, even informally tautological.
Soul's don't have that kind of support.
However, I find bringing the concept of "soul" into the equation to be helpful, because many people intuitively believe in such things. If you ask them if souls are important, they'll say yes. If you ask them if something special happens to souls after death, they might say yes. But ask them to define what they mean when they say "soul", and you'll get a ton of hand-waving. People can believe very strongly in things they can't even describe or point to: this always puzzles me, because it shows that people don't even know what it is they believe in in the first place.
Whether the concept of "consciousness" is as ridiculous as the concept of a "soul" or not, I have found that they both suffer from the same definition problem.
There are many, many concepts which throughout History entire societies have shared a belief in, but which didn't map to real things that could be defined precisely. A "soul" is one of those, but other examples abound in the History of science and in the History of medicine.
Colors, sounds, tastes, smells, feels, emotions that makeup perception, imagination, inner dialog or visualization, dreams, hallucinations, illusions.
Or qualia if you want to reference the philosophy of mind literature, where the debate and various positions are well defined and extensively argued.
All of which are things we can explain without any magic.
The literature on qualia pretty much has the same problem as the literature on consciousness.
The "Why is red RED?" thing is a complete joke from a scientific standpoint.
> Every aspect of your experience is your nervous system and the sensory organs at work
There's still a leap from that to the existence of subjective experience.
It's almost like by insisting that there is a subjective experience (as opposed to what?) you close your eyes to how that experience arises, and prefer instead to implicitly attribute it some magical attributes such that it can never be explained mechanically.
BUT, we are SO similar genetically that there is SHARED properties to nearly all experiences among ALL humans, strongly arguing for objectivity to it.
Why is red specifically what we perceive as red is not answerable. How it affects you cognitively and emotionally is based on the entirety of your upbringing and past experiences as well as your sense neurology. Our brain has quite a lot of neurons and connections! Trillions of connections and billions of neurons! A lot can change and be affected in innumerably complex ways! It's more than sufficient to explain the entirety of our subjective experience.
This control and access, which needs a true observer, is consciousness. If a computer is taken as layer of reality, then this control is in outside layer of reality. But we don't stop there: It is observer in all layers of reality, whatever reality is made of. The observer can never be represented in any layer of reality.
We should consider that experience layer, like sound and vision are an independent layer of reality than underlying "material" reality. A materialist will say latter exists a priory, and thus experience is off the material layer. But we can as well argue that experience layer is a-priori. My taste sense, for e.g. has no equivalence in material reality. It deserves its own layer of reality. If I hear a voice of someone, it is singular experience rather than experience of collection of frequencies. Color like white is an experience of multiple frequencies of light. Our perceptions, happening with help of neurons, are not based on light at all. Projection is a-priory present, from which we create even light and other formulations...
A mathematical reality is in its own layer of reality. A conceptual reality of say, chair, is also in a "mental" reality.
So we should assume that all are simply abstract layers of reality. But our mental conditioning has created "things" model, just because we can touch and feel, or perceive a boundary in what we see.
As observer, which creates memory of observation, and accesses it, all in the present. An observation which is not in time and space, but creates sense of time and space out of observation.
And so on... A totally different model of reality.
https://www.amazon.com/Consciousness-Emily-Troscianko-Susan-...
She has another book called Conversations on Consciousness that's basically transcribed interviews with prominent figures that's also worth checking out.
https://www.goodreads.com/book/show/254499.Conversations_on_...
Yes this comment is an ad hominem, and no I have not read the book... All I have is a skeptical hunch that this might not represent "the state of the art" on the topic.
From her wiki page:
It was just over thirty years ago that I had the dramatic out-of-body experience that convinced me of the reality of psychic phenomena and launched me on a crusade to show those closed-minded scientists that consciousness could reach beyond the body and that death was not the end. Just a few years of careful experiments changed all that. I found no psychic phenomena—only wishful thinking, self-deception, experimental error and, occasionally, fraud. I became a sceptic.
It is also a natural consequence of the culture you happen to have been raised in, which is an extremely interesting aspect of consciousness: how easily it can be programmed, and how influential it can be (it changes how reality "is"). In your case you have self-awareness of the phenomenon, at least in this case, but most people don't operate on that level.
* After spending time in research on parapsychology and the paranormal,[5] her attitude towards the field moved from belief to scepticism.[6][7] In 1987, Blackmore wrote that she had an out-of-body experience shortly after she began running the Oxford University Society for Psychical Research (OUSPR):[8][9]
"Within a few weeks I had not only learned a lot about the occult and the paranormal, but I had an experience that was to have a lasting effect on me—an out-of-body experience (OBE). It happened while I was wide awake, sitting talking to friends. It lasted about three hours and included everything from a typical "astral projection," complete with a silver cord and duplicate body, to free-floating flying, and finally to a mystical experience. It was clear to me that the doctrine of astral projection, with its astral bodies floating about on astral planes, was intellectually unsatisfactory. But to dismiss the experience as "just imagination" would be impossible without being dishonest about how it had felt at the time. It had felt quite real. Everything looked clear and vivid, and I was able to think and speak quite clearly."
In a New Scientist article in 2000, she again wrote of this:
"It was just over thirty years ago that I had the dramatic out-of-body experience that convinced me of the reality of psychic phenomena and launched me on a crusade to show those closed-minded scientists that consciousness could reach beyond the body and that death was not the end. Just a few years of careful experiments changed all that. I found no psychic phenomena—only wishful thinking, self-deception, experimental error and, occasionally, fraud. I became a sceptic.[10][11]"
* She is a Fellow of the Committee for Skeptical Inquiry (formerly CSICOP)[12] and in 1991, was awarded the CSICOP Distinguished Skeptic Award.[4]
* Susan Blackmore has made contributions to the field of memetics.[19] The term meme was coined by Richard Dawkins in his 1976 book The Selfish Gene. In his foreword to Blackmore's book The Meme Machine (1999), Dawkins said, "Any theory deserves to be given its best shot, and that is what Susan Blackmore has given the theory of the meme."[20] Other treatments of memes, that cite Blackmore, can be found in the works of Robert Aunger: The Electric Meme,[21] and Jonathan Whitty: A Memetic Paradigm of Project Management.[22]
This is all from her wikipedia, which is about a one minute read.
As I recall, her consciousness textbook is fairly opinionated but it still gives a fair tour of the mainstream theories. She happens to be an illusionist like Dan Dennett. There's no "woo" in her coverage of the topic.
There's a recent book called "Conscious: A Brief Guide to the Fundamental Mystery of the Mind" which purports to be what you are looking for. She's an author who is married to Sam Harris, a neuroscience PhD and public thinker who focused a lot of consciousness. His ideas permeate her thinking and I found her treatment to be less open minded.
There's a series mirrored on YouTube called "Closer to Truth", where Robert Lawrence Kuhn interviews famous physicists, mathematicians, etc. on this and other grand unsolved questions. You can find interviews with most of the analytical thinkers in the consciousness space if you wade through.
The most "mathematically rigorous" theory is Integrated Information Theory by Giulio Tononi. The logical conclusions of his theory are outlandish or eye-opening, depending on your bias. I don't buy it myself but the there might be something in the approach.
The most mathematically gifted individual with a theory is Roger Penrose. His scientific work is absolutely brilliant but his ideas about consciousness are quite frankly ridiculous and unmotivated.
The best, most rigorous theory I know of comes from a Neuroscientist at Princeton named Michael Graziano. He put forth the "Attention Schema Theory". I strongly recommend his book "Rethinking Consciousness" which makes a case for it, and provides an overview of the other approaches and how they relate to his ideas.
I've been very much swayed by Graziano's work, and we have the technology today to test his theory by integrating actively controlled attention mechanisms into machine learning models. If his ideas are correct, that could lead to models organically making similar claims to humans regarding phenomenological states. The theory is agnostic about whether the claims would be substantiated.
Altered States of Consciousness: Experiences Out of Time and Self (The MIT Press) https://a.co/d/ghPhlDW