Qualia exist. That's how we know that anything exists.
When a line of argument is based upon the existence of an invisible element that can't be shown or detected, it starts to veer into the territory of religion. If there's no evidence beyond "I feel it must be true," its important to acknowledge that others might feel differently.
All of that leaves off the red experience. There is no red experience in the physical world of things anymore than a tomato actually has an objective smell or taste. Those are all mental and creature dependant (carrion likely smells and tastes wonderful to vultures but not humans).
Somehow, this is strongly correlated with perception and the brain, but how is a deep mystery. This isn't to deny the brain or the eye's role in experiencing red, only that we don't have an explanation for how the red experience is present, when none of those things (or processes) are objectively red.
You claim that there's some other invisible force at work when this happens, but what evidence is there to back that up? It seems like the mechanical description does a pretty accurate job of describing what's happening. Neuroscientists who have studied this don't seem to be running into any issues. Not only is there no evidence for qualia, but the idea of qualia doesn't seem to even solve any particular problem.
Machines detect wavelengths of light. That's not what a color experience is. Photons aren't literally colored red or green. That's just how we see objects when the cones in our eyes are excited, sending electrical signals to our visual cortex.
This is more obvious with smell and taste, since that greatly depends on an animal's sensory apparatus. Nothing has an objective smell or taste.
> You claim that there's some other invisible force at work when this happens,
But I made no such claim. I'm only pointing out how the problem is hard. I have no idea what the answer is.
Right. We detect certain wavelengths, which activate certain receptors, which send out certain signals, which cause certain neurons to fire. The "color experience" is the neurons firing and how that interacts with other neuronal activity. I'm not seeing where the need for qualia is, or what's particularly hard about this.
This is one way to go which possibly solves the problem. But it's not without difficulty. One is that it's hard to see (pun unintended) how the explanation for neuronal activity is the same thing as having a red experience.
Second problem is that it makes the physical system of brain activity special. Searle might be down with that, but it won't help machine detectors have a red experience. Or maybe even aliens, if they're made of something other than meat.
It's also hard to see what makes neuronal activity any more special than the cells in your toes or molecules in a rock. Why can't a rock have a red experience when interacting with light at that wavelength?
I guess I don't understand why that's hard to see. It seems pretty straightforward to me. We know that neuronal activity is necessary for the experience, we know that it coincides with the experience, and we know that changing how neurons operate can effect the experience. It doesn't seem like a stretch to say that they are the experience.
> Second problem is that it makes the physical system of brain activity special...It's also hard to see what makes neuronal activity any more special than the cells in your toes or molecules in a rock. Why can't a rock have a red experience when interacting with light at that wavelength?
If we're defining "red experience" as the neuronal activity that humans have when they see red, your wondering why a rock can't have that? I mean, because it's a rock that doesn't have a single neuron, let alone a human brain?
But beyond that - are there people that actually argue that brain activity isn't special? You're not going to have a "red experience" if you have no brain activity.
Because brains are made up of ordinary matter, just like rocks. If it's the behavior of neurons that's special, then consciousness is no longer identical with neurons, it's identical with any physical system that functions the same way. And then you have the possibility of very counterintuitive arrangements, like a billion Chinese instantiating a blue experience, or a meteor shower simulating experiences.
> We know that neuronal activity is necessary for the experience, we know that it coincides with the experience, and we know that changing how neurons operate can affect the experience. It doesn't seem like a stretch to say that they are the experience.
But what is it about neurons that make them experiential? And only some neurons, because a lot of neuronal activity is not conscious.
Sure, I don't think brain uploads are impossible. If we were having this conversation in 100 years, I might be saying that "red experience" is the result of neuronal/circuit activity. But functions the same way is the relevant part - a rock does not function the same way. I don't think either of us expect a human to act the same way if their brain is replaced by a rock. On some level, we both know that the brain is fundamentally different from a rock.
> And then you have the possibility of very counterintuitive arrangements, like a billion Chinese instantiating a blue experience, or a meteor shower simulating experiences.
I think we can both agree that a computer is merely a physical object. That doesn't mean that surfing the web or playing a video game on "a billion Chinese"/"a meteor shower" is any less counterintuitive. Imagining any incredibly complex system being completely simulated by random physical phenomena is bizarre.
And the human brain is much, much more complex than a laptop. Really, go read up on it - 86 billion neurons, 100 trillion synapses, neurons firing 200 times a second. Consider the work it takes to simulate one second of brain activity (with far fewer neurons and synapses than a human brain)[1]:
> The simulation involved 1.73 billion virtual nerve cells connected by 10.4 trillion synapses and was run on Japan's K computer, which was ranked the fastest in the world in 2011.
> It took the Fujitsu-built K about 40 minutes to complete a simulation of one second of neuronal network activity in real time, according to Japanese research institute RIKEN, which runs the machine.
> The simulation harnessed the power of 82,944 processors on the K computer, which is now ranked fourth on the biannual international Top500 supercomputer standings (China's Tianhe-2 is the fastest now).
You're far more likely to see the dust in the air randomly play Casablanca for you from start to finish than you are for meteor showers to randomly start simulating the human brain. The human brain is complex. Really, really, really complex. So complex that weird emergent stuff like "red experience" happens. People have a hard time conceptualizing things when they become so vast; that's understandable. But there's no need to invent invisible qualia simply because we have a hard time understanding things on this scale.
[1] https://www.cnet.com/news/fujitsu-supercomputer-simulates-1-...
goatlover has explained it well: Subjective awareness exists. "Qualia" is a name for the content of awareness. We know awareness exists because we have it (or are it.) We literally know nothing except as qualia.
The content of awareness is obviously mediated by our nervous system, but the subjective experience of "redness" is a mystery. (To take a simple example.)
Why is red red?
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edit: Chathamization what do you mean when you say "qualia"?
Well, as I said in an earlier post, I'm talking about the existence of qualia "beyond being a vague description for emergent properties arising from our cells." People have a sense of self, sure, and people experience things. But usually the people who bring up "qualia" seem to think that our sense of self can't be explained as simply being neuronal activity.
For instance, "redness" doesn't seem to be mysterious at all to me. Our brains fire in a certain way when presented with certain stimuli. As for why they fire in that particular way, it's complicated because the brain is complicated (and each persons brain is unique). But it's a complicated physical system (and one that we're gaining a better understanding of each day).
Light of a certain frequency, neurons, "and then a miracle occurs", and "I" experience red...
With all due respect you're eliding that bit in the middle.
In my understanding, this "miracle" is human general intelligence. I think that any dynamic pattern-matching and model-building entity will experience a certain degree of "consciousness". Conscious experience is the entity's internal modeling of its own sensory input [1]. And likewise, conscious thought is the entity's modeling of its own internal state and processes (including the modeling process itself).
[1] This includes things like seeing my friend walk down the street. This sensory input is incredibly more difficult to model than in an alternative scenario where I'm looking at a red apple resting on a table.
When people first witnessed the steam governor [1] it was common to say that it seemed alive.
What you and the other guy are basically saying is that if we pile up a bunch of cybernetic devices together you eventually pass a threshold where subjectivity (aka consciousness) begins.
Now, I don't agree nor do I disagree.
My point is that we are far from having a scientific theory that says how this happens. It's no good to wave ones hands and say, "Complexity!" or "Model-building." I want to know why red looks red as opposed to some other sensation?
We can't even describe sensory inputs! We can only correlate our experience with the reports of experiences of others. Maybe you see "green" and I see "blue" when we both look at a "red" object. How can we "do science" to/on subjectivity?
Really, I'm just glad that people (in the West) are finally taking this seriously.
[1] https://en.wikipedia.org/wiki/Centrifugal_governor\
Edit: my original point was just that "qualia" (which I use as a name for the content of awareness) exist. I don't know what it would mean to deny the existence of the contents of awareness, since we quite literally only know anything by way of those contents.
The gist of this seems about right, although the configuration of the components is likely to be just as important as the raw quantity.
I would also argue that there is a spectrum of gradient of consciousness (or awareness, sentience, etc), likely without a clear starting threshold. As an analogy, perhaps it is similar to how the boundary edge of a cloud in the sky is impossible to define, but there isn't much disagreement about which parts of the cloud are bulky.
> my original point was just that "qualia" (which I use as a name for the content of awareness) exist
For you, qualia is synonymous with awareness? I've generally heard it described as the ephemeral aspects of subjective experience.
I'm fairly skeptical of the way many people talk about "subjective experience", as there often seems to be a large amount of unspoken assumptions involved. The biggest one being that there is an irreducible, singular entity or "subject" having the experience.
I find awareness to be a concept with less assumptions -- to me, it doesn't imply a "subject" to the same degree. Thus I'm more comfortable with your definition of qualia, although I wonder if others share it.
If we recast the subject as primary vs secondary qualities, where primary qualities are non-observer dependant properties like number, shape, extension and secondary are observer-dependant properties like color, sound, taste, then it's easier to understand the issue.
Science provides an account of the world that is colorless, soundless, soundless, tasteless But we experience the world as having colors, sounds, tastes, so where do those come from?
I argued a few comments above that those experiences are the product of the powerful modeling apparatus of the human brain, the same thing that likely enables our broad intelligence, turning inward on itself.
Those experiences are the manifestation of the system modeling itself: its sensory inputs, internal states and processes, and, in a recursive fashion, some of the modeling processes themselves. The richness of these experiences gives us a clue at how sophisticated the modeling ability of the brain actually is.
No, it isn't.
> There is no red experience in the physical world of things
There is no way of showing that the subjective “red experience” is not simply a label applied to a particular set of conditions in the “physical world of things”.
> This isn't to deny the brain or they eye's role in experiencing red, only that we don't have an explanation for it.
There's a huge difference between “we can't explain the entire relationship between physical conditions and subjective experience”(which is true but does not require qualia) and “subjective experienced involve something outside of physical conditions” (which is unprovable—not merely in practice, but in principle—but necessary for qualia to be a real, nonphysical thing.)
This can be turned around to say that there's no way of showing that a particular set of conditions in the "physical world of things (or processes)" isn't an abstraction from subjective experience.
Either way, you have an explanatory gap. I know I have red experiences. I know there are abstract explanations for how my visual system works, how objects reflect light, and so on, making it possible to see objects as colored. I don't see how the abstract explanation (the scientific one) explains my having a red experience, because an abstract explanation isn't the same thing as having an experience.
Sure, it can, and if someone said it was easy to show that o jective reality exists independent of subjective experience, that would even be relevant.
Of course, the difference is that the concept of an objective reality is a useful abstraction from subjective experience (it's what let's science, which has utility in predicting future experiences, exist). Qualia offers... what?
A way to clearly demarcate subjective experience. We don't have to use the term "qualia", but then people tend to use words like consciousness differently, and the debate ends up being a semantic one.
> the difference is that the concept of an objective reality is a useful abstraction from subjective experience
Agreed, and I think there is a real, objective world independent of our experiences. But to get at it, we do have to abstract from our consciousness. That works really well for most things, until we turn it around and try to explain the nature of our subjectivity. Qualia is philosophically specific term meant to highlight that difficulty.
What do you mean when you use the term "exist"?
I cannot fathom the semantic meaning of "qualia don't exist".
Either you are the legendary "P-Zombie" or you're using the words fundamentally differently than I am, I think.
I hope this doesn't sound offensive, and apologize in advance if so. I am genuinely and sincerely curious about this.