Rather than physics, I think computational neurology and machine learning / deep learning / AI have a much better chance at elucidating what consciousness is.
I can't tell whether you are being sarcastic or not. Machine learning has absolutely nothing to do with consciousness. From where people get that connection?
I don't think there is something magical in flesh. Consciousness is a process of constructing compact and effective representations of the external world which are necessary in order to learn behavior that maximizes rewards (survival). More sophisticated organisms also develop a model of the world and operate on it by imagination or memory recall, so there is also consciousness of internal mental processes. Such mental processes look like a neural turing machine (read from memory, write to memory, focus on specific parts of sensory field / attention). The mental programs to operate over memory and attention are learned by reinforcement learning. Physical control and operating in the external environment are learned by RL too. The notion of self and language emerge naturally from the need to cooperatively solve problems together with other agents. The teaching signal (reward) is based on the environment and inborn instincts (such as hunger, sleep, defense, sex, cooperation) which are evolutionarily evolved. Part of the perception process is based on unsupervised learning, where raw sense data is encoded in the latent semantic space and then, by a top-down process, is tested by regenerating the original input data. It learns by propagating the error (differences) from the data it generates compared to the original sense data. All these processes have been already implemented, albeit crudely, by machine learning.
Nothing? How do you mean that? Sure, it's not in the vicinity, e.g. machine learning has more to do with statistics and AI but nothing? I'm surprised by that statement, maybe I'm taking it too literal perhaps.
I mean, the way neural nets behave in computer vision implies some form of attention. On some benchmarks neurons and deep learning have almost the same biological output (poorly phrased, was from a talk that NG gave). Perceiving, or parts of perception have something to do with consciousness. Attention has something to do with consciousness.
And you don't have to agree on everything I say, I'm typing/thinking quickly. My point is: machine learning has at least something to do with consciousness.
Neural nets are loosely inspired from the brain (and a ton of math). So it could perhaps nuance certain neuroscientific findigs in some cases or the other way around (e.g., neural net designs for the visual system or other brain systems). Anyways, that's how I get the connection.
A stone brick and consciousness, that has nothing to do with each other, nothing practical/inspirational anyway.
Subjective experiences are neurologically evolved and psychologically optimized representations of sensory input. Using only the objective world we ought to be able to infer something about them. Your thought process here is interesting. Color is the optimal subjective encoding of light's frequency and amplitude. We use it to infer material (color) and structure (shading) when we're recognizing objects. The models inferred by machines almost necessarily have a similar shape; Provided they're being required to perform similar tasks. If we can make a neural network pass the Turing Test then it's model should tell us all sorts of things about humans.
I regret saying color was the optimal encoding. It's an optimal encoding. Also only for our visual instruments, required operations AND cognitive capacity. Different organisms likely have different sensations. I suspect consciousness is some form of self awareness. Our internal model of space is likely an aspect of this. Many/most organisms lack the neurology for this sort of modeling. They may still have consciousness in some form but I'm afraid to speculate about what it looks like. I'd want to see the Turing Test neural net compared to an ant neural net. That's the most apples to apples analysis I can think of. We can't cheat with awareness of our own subjectivity if we want to understand ourselves. We're never going to be ants. We will never know anything about color. Only how many frequencies and amplitudes of it different humans can detect.
It doesn't, but perhaps what many people are thinking is that in costructing more and more capable learning models, we'll get closer to what human brain does. It's not very likely, but hard to tell what will really happen. As an example, some of the deep dream pictures do really look like what people are hallucinating.
Visarga is saying the data provided by computational neuroscience is a good candidate for analysis by machine learning so that the we can find statistical patterns that may help elucidate the processes that we consciousness comes from.
Or Réné Descartes in the 17th century. The fundamental nature of res cogitans so to be conscious... if that rings any bells. :)
It's also an idea that few philosophers of mind agree with at this point. Gilbert Ryle did a pretty good job of showing that the mind-body problem is a pseudo-problem [0].
Have you read Gilbert Ryle's "The Concept of Mind" (1949) [0]?
This is a very old and tired argument. The form you seem to be endorsing has fallen out of favor in philosophy circles. For an intuitive understanding of why interactionist dualism is a bad explanation of phenomenology, consider the following problems:
- How does your non-physical substance (what you call a fundamental force in the universe) interact with a physical "antenna"?
- Given that this force interacts with matter (as evidenced by consciousness disappearing after certain brain injuries), how is it that it evades physical measure by scientific instruments?
It's a subjective experience, so I'm not sure we can reason very well about what anything fundamentally unlike ourselves subjectively experiences. I mean, I can program my computer to print out "I calculate, therefore I am" but who knows what, if anything, the processor experiences as it calculates that.
I you want to check the video I'd recommend to skip to approximately minute 13, as the beginning is pretty boring - 1 minute of musical introduction, then the hand of Edward Witten looking in his notes, and then some introduction in what I believe is Dutch.
See, if a neuroscientist went and had an opinion on sub-atomic physics, people would say "that's nice" and pat them on the head in a patronizing way. But the problem is general. A scientist outside their field is a layman.
If I was to give my unqualified, layperson opinion, I'd say "horse feathers". Consciousness probably isn't "hard" at all. It's a massively parallel brain architecture (which by its widely-spread and slow nature can't accurately self monitor) using theory-of-mind circuitry (developed to handle interpersonal social relations) to model and monitor its own operation.
But it feels more sparkly and special to treat it as a mystery.
You mostly don't self-experience. Mostly you experience what's going on around you, and what you're doing and physically feeling. Mostly, you don't act consciously. But when you direct attention at your own experiencing, or at your own actions in a deliberate way, a subsystem dedicated to that task wakes up and provides you with a homunculus self-model. That would be the 'I'.
And how do you get from a homunculus self-model to the subjective experience of the colour blue? (Or any other colour?)
...Which would be a subjective experience that seems to have curiously objective elements to it, because colours have been shown to correlate with specific sensations and associations across populations.
And then there's the much deeper question of the extent to which quantum phenomena need an objective observer.
If you think that question is trivial, try to design an experiment which provides objective evidence of change without ultimately relying on the subjective experience of a human experimenter.
They're separate, of course. People tend to over-attribute things to their consciousness. Blue is an analysis and categorization being done by the visual processing part of your brain. That part of your brain is grown by basically the same genes as everyone else's. It would be more surprising if it wasn't similar in operation.
Your subjectivity is your brain is you. But only tiny scraps of it are consciously accessible. Nearly all of it just does, it doesn't reflect on the doing. You only notice your visual processing when you force it to glitch or strain with optical illusions and the like.
As for the quantum stuff, it doesn't need a conscious observer at all. This is why an experimental qbit can decohere in a sealed box no human could possibly peek into. What it needs is one interaction whose result is contingent on state - that's a "measurement" or in unintentionally confusing terminology, an "observation".
It's one of the kinds of problem statements that gets habitually distorted by the technology we have to hand. Here we naturally envision it as something that a computational system might represent.
But as soon as we solve some fraction of the problem with scientific means, a small fragment remains to be probed further, still mysterious. Solve that and a yet smaller facet still remains, as in Zeno's paradox. That has been the case with AI, with simulations and physics models and medicine and most fields of study.
Our notion of the authentic is always on fragile ground, and this is most easily seen in music, where technology has enabled total control of the sound on a theoretical level of adding harmonics, but not in the practical sense of "reproduce this sound but make it Better". At the extreme ends it becomes a matter of taste again - why else should vinyl or vacuum tubes or analog filters remain so cherished? As we gain more technology, more of our lives enters this limbo where science can provide deductions that identify and change the measurable, but do not tell us how to pick good measures for ourselves. Philosophizing it is just a matter of continuing to ask those kinds of hard questions and inching forward ever so slightly each time.
When a distinguished but elderly scientist states that something is possible, he is almost certainly right. When he states that something is impossible, he is very probably wrong.
I have no evidence or proof, but personally, I believe that the whole consciousness thing is an illusion. There's certain level of abstraction required for a bran as advanced as human's, but in the end, it's just matter following the laws of physics, same as everything else.
The question is, which laws of physics, and are the interaction between those laws of physics, interactions we already know, or new ones we have not discovered yet?
Otherwise we might as well say consciousness follows the will of God.
In terms of brain, it seems that the classical physics and electromechanics is quite enough — we don't really need to invoke quantum physics to explain the basic neurons (except as by proxy with all chemical reactions), and current progress with neural networks shows that these structures can indeed result in extremely complicated behaviour.
Consciousness must exploit growing entropy somehow - otherwise we'd be completely deterministic and consciousness (as an orthogonal consequence of free will) could not exist.
Why? The engineering definition of deterministic implies predictable outcomes given a known internal state. Are you suggesting that we're already at the level where we can accurately and fully measure a human brain's internal state?
This is a philosophical discussion because neither the deterministic mind nor the non-deterministic mind can be disproven for exactly the reason that you specify. Scientifically measuring consciousness could be a fool's errand: the very nature of it is subjective.
That does not mean that we cannot discuss the likelihood of each explanation, keeping in mind that both explanations could be incorrect. We have Drake's Equation even though, for all we know, nobody has ever seen an extraterrestrial life-form. We have flight because nature demonstrated flight to us: nature continuously demonstrates the capability to evolve quantum machines (e.g. the nose and various other organic processes[1]).
Finally, the engineering definition of determinism is not the only definition.[2]
So we can't measure, touch or see conciseness (not brain activity - consciousness). We can't observe it, only experience it. Why do we expect classical physics to be up to the job of understanding this?
I agree with you. It certainly is following laws of physics (known and unknown) because everything is. It is a useful abstraction for a complicated system. However, it doesn't make it any less interesting for me.
Exactly. I tend to believe that we're taking "our" consciousness out of mutual observation of our interactions. Kinda like two machines with protocols. To themselves, the world exists because the other responds accordingly.
The problem with this language is that the very word "illusion" implies an observer.
To whom is it an illusion? And, what are the properties of this illusion? Can we make artificial minds that are also suffering from the same illusion?
The very fact that there is (let's suppose) such an illusion requires an explanation. Suppose the brain has somewhere encoded the idea of consciousness, but no "actual" consciousness. Why do we require the extra step of "actual" consciousness rather than mere "illusory" consciousness?
Of course the real explanation of consciousness will be both profound (beautiful, unexpected) and mundane (non supernatural).
> Of course the real explanation of consciousness will be both profound and mundane
The expectation of something does not guarantee its existence. Words are created to define the expectation of something unexplained, only to be discarded when the expectation is unmet.
Take the word "miasma". At some point in history, a belief was born that all diseases came from gaseous poisons emitted by rot. Then the miasma theory got definitely discarded when we got the ability to view germs, which are simply distant cousins. https://en.wikipedia.org/wiki/Miasma_theory
Take the word "aether". Since waves on the sea were carried by water and sound waves by air, it was assumed that interplanetary space was filled with a substance that light (assumed to be just a wave back then) was carried through. It was called aether. It turns out the real explanation of aether is not profound nor mundane: there is nothing, and that nothing expands. https://en.wikipedia.org/wiki/Aether_theories
I don't really understand why it is hard to accept that there is no after-life, that all our activities are the sole result of chemical transmission of signals in our brains... that there is no point of view, just local chemical storage of information.
But it was hard for our ancestors to fathom that humans were part of a phylogenetic tree encompassing all Earth life forms, that we as a species were not special. It was hard for them to fathom that space is relative, that there is no center. I suppose it is always hard to accept that there is no reference point in the universe.
> that there is no point of view, just local chemical storage of information.
You have just restated the problem of consciousness, except as an assertion that it doesn't exist.
The problem of reductionism is that it doesn't stop; just as there aren't really points of view, there aren't really any chemicals, and there isn't really such a thing as (classical, let's say) information. All of these things are "just" emergent phenomena.
The explanations which made "aether" and "miasma" obsolete are beautiful, unexpected at the time (in a trivial sense), and of course, not supernatural.
I agree with you about the afterlife. However consider this: if the universe is infinite, isn't it likely that there will be copies of you which arise spontaneously, in all conceivable circumstances? The older you get, the less likely you are to be in a place or time that is causally connected to your birth, because most causal chains involve your death. (This is just a specific case of a Boltzmann Brain[1])
Of course, this sort of nonsense thought experiment runs afoul of the Measure Problem [2]. But this is precisely the kind of problem that I hope the explanation of consciousness would help to resolve.
> You have just restated the problem of consciousness, except as an assertion that it doesn't exist.
Things that don't exist are rarely problematic. But in fairness, I cannot guarantee that there is no consciousness, just as I cannot guarantee that gravity exists — it could be part of a simulation in which I was put since birth, and the real world could have very different laws of physics. Nothing new here, it is Occam's razor.
> it doesn't stop; just as there aren't really points of view, there aren't really any chemicals, and there isn't really such a thing as (classical, let's say) information.
There is such a thing as a point of view. I object to the notion of consciousness solely because of how it is used. Plants have points of view too; jellyfish do too, without the need for a brain. They react intelligently to their environment. Are those conscious? It is clearer to talk about "brains" and "points of view" than it is to talk about "consciousness".
> The explanations which made "aether" and "miasma" obsolete are beautiful, unexpected at the time (in a trivial sense), and of course, not supernatural.
I suppose that's up to each of us to judge. I don't find the idea that throughout my body, millions of tiny unicellular parasites are having a snack, particularly beautiful. Similarly, the idea that there is an invisible energy pulling everything apart always felt supernatural to me.
> if the universe is infinite, isn't it likely that there will be copies of you
The probability is above zero, but given that space is overwhelmingly empty, and given how much information defines my identity (including my average DNA, which is inherited from millions of years of evolution in extremely specific circumstances), it seems unlikely. If there is a copy of me in the universe, the most probable location would be on Earth, extremely close to where I sit.
I'm not sure I can buy that it's an illusion. That seems too contrary to my intuition. But it certainly could be something very different than we think. There's still a lot of momentum behind older concepts where you substitute "consciousness" for "soul".
For example, you could find out that consciousness is a real phenomenon but that it's experienced by more matter than we think, but without as much depth or ability to express itself as the human neocortex. Or perhaps each of us has multiple consciousnesses within, but we can't sense it because they all share the same memories and have essentially the same desires and feelings. Who knows! But it could be substantially different than how we frame a singular, soul-like consciousness
> perhaps each of us has multiple consciousnesses within
You're not far from the truth. Every piece of your brain still alive works roughly as the whole, even when cut off from the rest. Every part of it can make complex decisions (although past a certain size, it's not going to be very smart).
I've read a critique of this approach, which critiques the basis of this assumption - "laws of physics". It goes like, that living systems does not follow laws of physics completely, but rather, as time progresses, establish new laws. And we have the word Emergence now. New laws emerge from within the interactions of the system, they are not posed apriori.
Would be happy if someone more knowledgeable could elaborate.
If the simulation theory is true, our memory, and all brain activity is done in the simulation (aka real world), but consciousness no. With no consciousness we could have a identical behavior, we would be intelligent zombies. Its cool to think that the world is rendered only when conscious beings see the world ("is the moon there when nobody looks?"). Or... are YOU the only one with consciousness? :)
This reminds me rather of Roger Penrose's foray into consciousness in The Emperor's New Mind.
If you wade your way through it, you'll find the tl;dr is 'consciousness must be a quantum thing because quantum things are mysterious and so is consciousness- oh and look at those microtubules in those neurons - you might get quantum effects in there.'
Kind of a snide way to dismiss Penrose's work. If our brains are doing things that algorithms can't and QM really is non-deterministic then there could be something to his book. I don't think we know enough to say yet.
What's disappointing is you thinking your one sentence is a trump card dismissing Orch-OR - orchestrated objective reduction. Perhaps better to say that you don't find his ideas on this subject convincing. That at least is not patronizing.
Yep. Penrose's argument goes something like this (oversimplified): 1) Turing machines can't solve the halting problem. 2) Humans can solve the halting problem. 3) Therefore, humans can't be Turing machines.
There are two problems with this line of reasoning. The first problem is that 2) is unsubstantiated. A human can see immediately that 15 = 3 x 5, but this doesn't mean that we have a magical ability to factor integers instantly. By the frivolous theorem of arithmetic, almost all natural numbers are very, very, very large. We have some ability to analyze formal systems, but the systems we have managed to understand are very simple in the grand scheme of things. Almost all formal systems are very, very, very complex, and there is no evidence that we can understand them all and/or that our understanding process actually is correct (consistent) when extended indefinitely. Penrose's actual argument is of course more technical, and others have made more precise rebuttals.
The second problem is that the argument does not solve the problem of consciousness. Scott Aaronson put it nicely: "Even if we supposed the brain was solving a hard computational problem, it's not clear why that would bring us any closer to understanding consciousness. If it doesn't feel like anything to be a Turing machine, then why does it feel like something to be a Turing machine with an oracle for the halting problem?"
In my experience all those "consciousness is otherworldly magic" people are at least heavily influenced (1) by the religious interpretation of the "magical uniqueness" of the humans compared to the all other living beings. Wishful thinking. Then comes the "free will" and other also "magical" thinking. Especially easy to sell in the US (2)
And we aren't made of anything other than what all the animals are made of, and the underlying processes in our brains aren't physically unique. And there's no "spirit" or "soul" needed to explain anything.
The word spirit comes from Latin spiritus "breath." Ditto for the term for soul "psyche" which comes from the ancient Greek psykhe with the original meaning "breath." That's all that "leaves us" when we die (as we "have our last breath") and from where all the magical thinking came.
The consciousness is just a product of evolution, and "a kind of self awareness" exists by animals too. Not much different from what we observe by ourselves, and actually of direct evolutionary advantage.
1) if themselves not explicitly declared believers or at least philosophers, the latter having all the incentives to mystify the topic and stay away from the hard sciences
For the same reason we don't calculate exact solutions to large travelling salesman problems; it's much more economical and evolutionarily advantageous to use heuristics, even if they have quirky side-effects and edge-cases.
It may be a mystery for some time, but I suspect we'll figure it out eventually. Given the rapid pace medical science understanding has gone through in the last several hundred years, it seems likely.
I like his approach very much, but I think he is a bit too generous with the artistic license and short on actual research, which is the opposite with Dehaene. I might be wrong of course. But Graziano is perhaps the best writer among current neuroscientists.
> But I think there probably will remain a level of mystery regarding why the brain is functioning in the ways that we can see it, why it creates consciousness or whatever you want to call it. How it functions in the way a conscious human being functions will become clear. But what it is we are experiencing when we are experiencing consciousness, I see as remaining a mystery...
Understanding the difference between __workings__ and experience of consciousness, the hard problem of consciousness [1], is crucial for understanding what Witten says. Witten says that while science will figure out how mind works in great detail the hard problem of consciousness remains outside science.
It's easy to be sympathetic to Witten. The problem with consciousness seems to be with intuitive meaning of a word and concept.
Imagine that someone builds small programs -- or really small brains in a vat -- that are conscious of color blue, or feel universal love and nothing else. Program's attention and awareness never goes elsewhere and it performs no other cognitive tasks than being conscious in the moment without long term memory. Can you imagine scientists going trough the __workings__ -- code, neuron diagrams or state representations -- of it's mind and going, oh this thing clearly conscious, we can see it now and agree.
There seems to be assumption that the hard problem of consciousness is tied to multiple high level cognitive capabilities. I don't see the connection. The crux of being conscious is having the cognitive ability of aware-consiouns-attentative-reflective at least tiny amount of time. If we could scientifically determine what consciousness is, we should be able to make nice hyper-aware-of-blue-and-knowing-it program and it would be relatively simple one.
Of course it will remain a mystery until we can get to an agreed definition of what consciousness is. Until then it is just an argument in semantics.
On a personal note I have never been very impressed with arguments over the importance of consciousness. I have had too many experiences in life where consciousness is grey to feel it is anything other than a just-so story of what happened.
Personal opinion: I can imagine that the reason of how we experience consciousness might be unsolvable, much as the question how the color blue feels is hard to answer objectively.
However, I think there are a lot less fuzzy questions that are strongly connected with consciousness that I'm hoping can be find answers for - and that could shed some more light on what consciousness is and what it isn't. Such as:
- what are memories? Could we build some machine to extract or even manipulate them? Is it possible to compare memories of different people?
- what are dreams?
- different parts of our body are affected differently by our consciousness: Some things we can control directly, like hands, feet, speech, etc; some processes we cannot control but we do experience them, such as hunger or sleep; and some we neither control nor experience such as digestion, homeostasis etc, even though they are also regulated by the brain. Even more couriously, many of those autonomous processes are greatly affected by conscious thoughts even though we don't experience them as directly controllable - such as fear and arousal. Inversely, conscious actions often have autonomous "sub routines", such as walking.
So what what mechanism in the brain governs which processes are conscious and which are not?
- Suppose we could actually do brain transplants. Assume we put an adult human brain in a jar and connect it with some kind of VR. Could the brain learn to control a non-human body such as a spider? How about a human body with different proportions?
These are all part of the easy problem of consciousness, so yes, I don't think anyone doubts that they can be answered in principle. But there's the hard problem of consciousness, which this article talks about.
I would also read Daniel Dennett's Consciousness Explained for a counter-point about why "Mary the super-scientist" is based on a faulty premise, and why the Hard/Easy distinction is fallacious.
I would point out some memories are image based and some are not, at least in those who visualize. "What are visualizations?" would be good to add to your list. Visualization appears to be a widely varied ability, yet we know very little about how the ability works, what function it provides to the visualizers and how it can be used to affect change in reality. Some of us have no visualization capabilities. Some have very advanced capabilities. Why?
> The end of science really is the end of the search for final causation.
Causation is everything. It governs from individual choice to the speed of light. Visualizations are internal perceptions that mimic the effect of light on our awareness. Where do those come from and is causality respected in them? Answer that, and you answer the consciousness question.
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[ 3.1 ms ] story [ 151 ms ] threadMe too. Sometimes one informs or inspires the other, but so far it seems that is about it.
Deep Mind has stated that their purpose this year is to build a rat level AI (https://www.youtube.com/watch?v=MAMuNUixKJ8). That would entail rat-level consciousness too.
I mean, the way neural nets behave in computer vision implies some form of attention. On some benchmarks neurons and deep learning have almost the same biological output (poorly phrased, was from a talk that NG gave). Perceiving, or parts of perception have something to do with consciousness. Attention has something to do with consciousness.
And you don't have to agree on everything I say, I'm typing/thinking quickly. My point is: machine learning has at least something to do with consciousness.
Neural nets are loosely inspired from the brain (and a ton of math). So it could perhaps nuance certain neuroscientific findigs in some cases or the other way around (e.g., neural net designs for the visual system or other brain systems). Anyways, that's how I get the connection.
A stone brick and consciousness, that has nothing to do with each other, nothing practical/inspirational anyway.
It's also an idea that few philosophers of mind agree with at this point. Gilbert Ryle did a pretty good job of showing that the mind-body problem is a pseudo-problem [0].
[0] https://www.amazon.com/Concept-Mind-Gilbert-Ryle/dp/02267329...
Have you read Gilbert Ryle's "The Concept of Mind" (1949) [0]?
This is a very old and tired argument. The form you seem to be endorsing has fallen out of favor in philosophy circles. For an intuitive understanding of why interactionist dualism is a bad explanation of phenomenology, consider the following problems:
- How does your non-physical substance (what you call a fundamental force in the universe) interact with a physical "antenna"?
- Given that this force interacts with matter (as evidenced by consciousness disappearing after certain brain injuries), how is it that it evades physical measure by scientific instruments?
[0] https://en.wikipedia.org/wiki/The_Concept_of_Mind
Personally I'd leave it to the philosophy guys since we're that far from any understanding of it.
But it feels more sparkly and special to treat it as a mystery.
...Which would be a subjective experience that seems to have curiously objective elements to it, because colours have been shown to correlate with specific sensations and associations across populations.
And then there's the much deeper question of the extent to which quantum phenomena need an objective observer.
If you think that question is trivial, try to design an experiment which provides objective evidence of change without ultimately relying on the subjective experience of a human experimenter.
Your subjectivity is your brain is you. But only tiny scraps of it are consciously accessible. Nearly all of it just does, it doesn't reflect on the doing. You only notice your visual processing when you force it to glitch or strain with optical illusions and the like.
But as soon as we solve some fraction of the problem with scientific means, a small fragment remains to be probed further, still mysterious. Solve that and a yet smaller facet still remains, as in Zeno's paradox. That has been the case with AI, with simulations and physics models and medicine and most fields of study.
Our notion of the authentic is always on fragile ground, and this is most easily seen in music, where technology has enabled total control of the sound on a theoretical level of adding harmonics, but not in the practical sense of "reproduce this sound but make it Better". At the extreme ends it becomes a matter of taste again - why else should vinyl or vacuum tubes or analog filters remain so cherished? As we gain more technology, more of our lives enters this limbo where science can provide deductions that identify and change the measurable, but do not tell us how to pick good measures for ourselves. Philosophizing it is just a matter of continuing to ask those kinds of hard questions and inching forward ever so slightly each time.
When a distinguished but elderly scientist states that something is possible, he is almost certainly right. When he states that something is impossible, he is very probably wrong.
"Just because Witten is a genius does not mean he is infallible. He is wrong, I believe, that string theory will eventually be validated,..."
The question is, which laws of physics, and are the interaction between those laws of physics, interactions we already know, or new ones we have not discovered yet?
Otherwise we might as well say consciousness follows the will of God.
Why? The engineering definition of deterministic implies predictable outcomes given a known internal state. Are you suggesting that we're already at the level where we can accurately and fully measure a human brain's internal state?
That does not mean that we cannot discuss the likelihood of each explanation, keeping in mind that both explanations could be incorrect. We have Drake's Equation even though, for all we know, nobody has ever seen an extraterrestrial life-form. We have flight because nature demonstrated flight to us: nature continuously demonstrates the capability to evolve quantum machines (e.g. the nose and various other organic processes[1]).
Finally, the engineering definition of determinism is not the only definition.[2]
[1]: http://www.bbc.com/earth/story/20160715-organisms-might-be-q... [2]: https://en.wikipedia.org/wiki/Deterministic_system_(philosop...
To whom is it an illusion? And, what are the properties of this illusion? Can we make artificial minds that are also suffering from the same illusion?
The very fact that there is (let's suppose) such an illusion requires an explanation. Suppose the brain has somewhere encoded the idea of consciousness, but no "actual" consciousness. Why do we require the extra step of "actual" consciousness rather than mere "illusory" consciousness?
Of course the real explanation of consciousness will be both profound (beautiful, unexpected) and mundane (non supernatural).
The expectation of something does not guarantee its existence. Words are created to define the expectation of something unexplained, only to be discarded when the expectation is unmet.
Take the word "miasma". At some point in history, a belief was born that all diseases came from gaseous poisons emitted by rot. Then the miasma theory got definitely discarded when we got the ability to view germs, which are simply distant cousins. https://en.wikipedia.org/wiki/Miasma_theory
Take the word "aether". Since waves on the sea were carried by water and sound waves by air, it was assumed that interplanetary space was filled with a substance that light (assumed to be just a wave back then) was carried through. It was called aether. It turns out the real explanation of aether is not profound nor mundane: there is nothing, and that nothing expands. https://en.wikipedia.org/wiki/Aether_theories
I don't really understand why it is hard to accept that there is no after-life, that all our activities are the sole result of chemical transmission of signals in our brains... that there is no point of view, just local chemical storage of information.
But it was hard for our ancestors to fathom that humans were part of a phylogenetic tree encompassing all Earth life forms, that we as a species were not special. It was hard for them to fathom that space is relative, that there is no center. I suppose it is always hard to accept that there is no reference point in the universe.
You have just restated the problem of consciousness, except as an assertion that it doesn't exist.
The problem of reductionism is that it doesn't stop; just as there aren't really points of view, there aren't really any chemicals, and there isn't really such a thing as (classical, let's say) information. All of these things are "just" emergent phenomena.
The explanations which made "aether" and "miasma" obsolete are beautiful, unexpected at the time (in a trivial sense), and of course, not supernatural.
I agree with you about the afterlife. However consider this: if the universe is infinite, isn't it likely that there will be copies of you which arise spontaneously, in all conceivable circumstances? The older you get, the less likely you are to be in a place or time that is causally connected to your birth, because most causal chains involve your death. (This is just a specific case of a Boltzmann Brain[1])
Of course, this sort of nonsense thought experiment runs afoul of the Measure Problem [2]. But this is precisely the kind of problem that I hope the explanation of consciousness would help to resolve.
[1] https://en.wikipedia.org/wiki/Boltzmann_brain
[2] https://en.wikipedia.org/wiki/Measure_problem_(cosmology)
Things that don't exist are rarely problematic. But in fairness, I cannot guarantee that there is no consciousness, just as I cannot guarantee that gravity exists — it could be part of a simulation in which I was put since birth, and the real world could have very different laws of physics. Nothing new here, it is Occam's razor.
> it doesn't stop; just as there aren't really points of view, there aren't really any chemicals, and there isn't really such a thing as (classical, let's say) information.
There is such a thing as a point of view. I object to the notion of consciousness solely because of how it is used. Plants have points of view too; jellyfish do too, without the need for a brain. They react intelligently to their environment. Are those conscious? It is clearer to talk about "brains" and "points of view" than it is to talk about "consciousness".
> The explanations which made "aether" and "miasma" obsolete are beautiful, unexpected at the time (in a trivial sense), and of course, not supernatural.
I suppose that's up to each of us to judge. I don't find the idea that throughout my body, millions of tiny unicellular parasites are having a snack, particularly beautiful. Similarly, the idea that there is an invisible energy pulling everything apart always felt supernatural to me.
> if the universe is infinite, isn't it likely that there will be copies of you
The probability is above zero, but given that space is overwhelmingly empty, and given how much information defines my identity (including my average DNA, which is inherited from millions of years of evolution in extremely specific circumstances), it seems unlikely. If there is a copy of me in the universe, the most probable location would be on Earth, extremely close to where I sit.
For example, you could find out that consciousness is a real phenomenon but that it's experienced by more matter than we think, but without as much depth or ability to express itself as the human neocortex. Or perhaps each of us has multiple consciousnesses within, but we can't sense it because they all share the same memories and have essentially the same desires and feelings. Who knows! But it could be substantially different than how we frame a singular, soul-like consciousness
You're not far from the truth. Every piece of your brain still alive works roughly as the whole, even when cut off from the rest. Every part of it can make complex decisions (although past a certain size, it's not going to be very smart).
See experiments on a patient with a severed corpus callosum: https://www.youtube.com/watch?v=zx53Zj7EKQE
Would be happy if someone more knowledgeable could elaborate.
The simulation hypothesis does not make such dualistic arguments.
If you wade your way through it, you'll find the tl;dr is 'consciousness must be a quantum thing because quantum things are mysterious and so is consciousness- oh and look at those microtubules in those neurons - you might get quantum effects in there.'
Rather disappointing for such a brilliant man.
There are two problems with this line of reasoning. The first problem is that 2) is unsubstantiated. A human can see immediately that 15 = 3 x 5, but this doesn't mean that we have a magical ability to factor integers instantly. By the frivolous theorem of arithmetic, almost all natural numbers are very, very, very large. We have some ability to analyze formal systems, but the systems we have managed to understand are very simple in the grand scheme of things. Almost all formal systems are very, very, very complex, and there is no evidence that we can understand them all and/or that our understanding process actually is correct (consistent) when extended indefinitely. Penrose's actual argument is of course more technical, and others have made more precise rebuttals.
The second problem is that the argument does not solve the problem of consciousness. Scott Aaronson put it nicely: "Even if we supposed the brain was solving a hard computational problem, it's not clear why that would bring us any closer to understanding consciousness. If it doesn't feel like anything to be a Turing machine, then why does it feel like something to be a Turing machine with an oracle for the halting problem?"
And we aren't made of anything other than what all the animals are made of, and the underlying processes in our brains aren't physically unique. And there's no "spirit" or "soul" needed to explain anything.
The word spirit comes from Latin spiritus "breath." Ditto for the term for soul "psyche" which comes from the ancient Greek psykhe with the original meaning "breath." That's all that "leaves us" when we die (as we "have our last breath") and from where all the magical thinking came.
The consciousness is just a product of evolution, and "a kind of self awareness" exists by animals too. Not much different from what we observe by ourselves, and actually of direct evolutionary advantage.
More about all that:
http://www.vice.com/read/sorry-religions-human-consciousness...
http://www.livescience.com/26338-crabs-feel-pain.html
http://backreaction.blogspot.com/2016/01/free-will-is-dead-l...
https://en.wikipedia.org/wiki/The_Demon-Haunted_World
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1) if themselves not explicitly declared believers or at least philosophers, the latter having all the incentives to mystify the topic and stay away from the hard sciences
2) 4 of 10 in the US believe "that God created humans in their present form 10,000 years ago: http://www.gallup.com/poll/170822/believe-creationist-view-h...
Exactly. Nothing makes sense in biology except in the light of evolution ( https://en.wikipedia.org/wiki/Nothing_in_Biology_Makes_Sense... ).
Why do some digger wasps only count their own contribution to a nest ( https://www.researchgate.net/publication/245965580_Do_Digger... ), and why do some perform redundant nest-checking ( https://en.wikipedia.org/wiki/Sphex#Uses_in_philosophy )?
For the same reason we don't calculate exact solutions to large travelling salesman problems; it's much more economical and evolutionarily advantageous to use heuristics, even if they have quirky side-effects and edge-cases.
https://www.amazon.com/Consciousness-Social-Brain-Michael-Gr...
An article by the same author:
http://www.theatlantic.com/science/archive/2016/03/phlegm-th...
> But I think there probably will remain a level of mystery regarding why the brain is functioning in the ways that we can see it, why it creates consciousness or whatever you want to call it. How it functions in the way a conscious human being functions will become clear. But what it is we are experiencing when we are experiencing consciousness, I see as remaining a mystery...
Understanding the difference between __workings__ and experience of consciousness, the hard problem of consciousness [1], is crucial for understanding what Witten says. Witten says that while science will figure out how mind works in great detail the hard problem of consciousness remains outside science.
It's easy to be sympathetic to Witten. The problem with consciousness seems to be with intuitive meaning of a word and concept.
Imagine that someone builds small programs -- or really small brains in a vat -- that are conscious of color blue, or feel universal love and nothing else. Program's attention and awareness never goes elsewhere and it performs no other cognitive tasks than being conscious in the moment without long term memory. Can you imagine scientists going trough the __workings__ -- code, neuron diagrams or state representations -- of it's mind and going, oh this thing clearly conscious, we can see it now and agree.
There seems to be assumption that the hard problem of consciousness is tied to multiple high level cognitive capabilities. I don't see the connection. The crux of being conscious is having the cognitive ability of aware-consiouns-attentative-reflective at least tiny amount of time. If we could scientifically determine what consciousness is, we should be able to make nice hyper-aware-of-blue-and-knowing-it program and it would be relatively simple one.
[1]: http://www.scholarpedia.org/article/Hard_problem_of_consciou...
On a personal note I have never been very impressed with arguments over the importance of consciousness. I have had too many experiences in life where consciousness is grey to feel it is anything other than a just-so story of what happened.
However, I think there are a lot less fuzzy questions that are strongly connected with consciousness that I'm hoping can be find answers for - and that could shed some more light on what consciousness is and what it isn't. Such as:
- what are memories? Could we build some machine to extract or even manipulate them? Is it possible to compare memories of different people?
- what are dreams?
- different parts of our body are affected differently by our consciousness: Some things we can control directly, like hands, feet, speech, etc; some processes we cannot control but we do experience them, such as hunger or sleep; and some we neither control nor experience such as digestion, homeostasis etc, even though they are also regulated by the brain. Even more couriously, many of those autonomous processes are greatly affected by conscious thoughts even though we don't experience them as directly controllable - such as fear and arousal. Inversely, conscious actions often have autonomous "sub routines", such as walking. So what what mechanism in the brain governs which processes are conscious and which are not?
- Suppose we could actually do brain transplants. Assume we put an adult human brain in a jar and connect it with some kind of VR. Could the brain learn to control a non-human body such as a spider? How about a human body with different proportions?
https://en.m.wikipedia.org/wiki/Hard_problem_of_consciousnes...
https://en.wikipedia.org/wiki/Knowledge_argument
http://philosophyfaculty.ucsd.edu/faculty/rarneson/Courses/F...
https://en.wikipedia.org/wiki/Consciousness_Explained
> The end of science really is the end of the search for final causation.
Causation is everything. It governs from individual choice to the speed of light. Visualizations are internal perceptions that mimic the effect of light on our awareness. Where do those come from and is causality respected in them? Answer that, and you answer the consciousness question.