So why would you trust your direct perception over the mountains of evidence that clearly demonstrates that we can't trust our perceptions?
So experience, aka qualia as a phenomena unto itself is in need of explaining, not any particular qualia and not the presence of absence of any correlation between the qualia and objective reality, i.e. the "truthfullness" or "accuracy" of the qualia.
Dennett wouldn't deny that either. He would simply say that we have no reason to think the qualitative experience of our perceptions are anything other than a cognitive trick with a functional purpose. Certainly how this trick works should absolutely be explained, and I don't think any materialist would deny that.
Here's why.
To explain qualia as a "trick" is to void the onotological status of qualia itself. He can't do that. It doesn't matter if it's all an illusion or a trick, it doesn't matter what its ultimate epistemological status is. Qualia is experienced and it's the experience itself, whatever its biological underpinning turns out to be (you can't have sight without eyes), which is relevant.
Yes, all experience could be fallible and illusory but the fact of experience itself cannnot be an illusion.
Experience qua experience is the thing no scientific theory of perception and cognition needs. So why does it exist? In other words, why are we not as not-conscious as rocks and chemical processes and planets and electrical activity, doing all we do, saying all the things we say? It's certainly possible.
Dennett, and I am inferring this I haven't heard him say it, is an ontological positivist. Only those things which the methods of science reveal to exist are "real" and everything else is, as you say, some kind of illusion. Sonunds good. But an illusion (which is some experience whose epistemology we have misconstrued) is not itself an illusion. Its ontgological status as "a thing which does exist" is secure.
Sure it can, and it remains only to explain how and why this illusion works to fool us into making erroneous statements, like "the fact of experience itself cannnot be an illusion".
> Experience qua experience is the thing no scientific theory of perception and cognition needs. So why does it exist?
It probably doesn't! Although I'm not as convinced as you that qualia are entirely non-functional.
> But an illusion (which is some experience whose epistemology we have misconstrued) is not itself an illusion.
What is an illusion? To my mind, an illusion is a perception or inference thereof that, taken at face value, entails a falsehood. So to call phenomenal consciousness an illusion is to say that the claims inferred from our direct perceptions are false, eg. "I have subjective awareness". There's nothing problematic about this that I can see.
But that is not the part of the illusion we're interested in. The part of it we're interested in is the part it shares with all other experiences. It was an experience. Stop. That fact can't be gainsayed.
What you're using to deny this is the epistemological status of the illusion experience. So that's things like "it was caused by brain cells XYZ firing" or "it did not accurately represent reality" or "it did not correspond to anything in reality at all". All those things could be true but they are beside the point being made.
Either one gets this fundamental idea or they don't in my experience (lol).
No one, not even eliminative materialists, would deny that people have what they believe to be phenomenal experience. See Frankish [1]:
> Does illusionism entail eliminativism about consciousness? Is the illusionist claiming that we are mistaken in thinking we have conscious experiences? It depends on what we mean by ‘conscious experiences’. If we mean experiences with phenomenal properties, then illusionists do indeed deny that such things exist. But if we mean experiences of the kind that philosophers characterize as having phenomenal properties, then illusionists do not deny their existence. They simply offer a different account of their nature, characterizing them as having merely quasi-phenomenal properties. Similarly, illusionists deny the existence of phenomenal consciousness properly so-called, but do not deny the existence of a form of consciousness (perhaps distinct from other kinds, such as access consciousness) which consists in the possession of states with quasi-phenomenal properties and is commonly mischaracterized as phenomenal.
[1] https://nbviewer.jupyter.org/github/k0711/kf_articles/blob/m...
And so far, this body of knowledge suggests strongly that we can't trust our perception of consciousness.
But perception is a part of conscious experience. We don't perceive consciousness independent of things in the world. They go hand in hand. So we know about the world because we have conscious experiences of perceiving the world.
What Dennett and others are trying to argue is that only the qualities of perception which are objective exist, even though those qualities are accompanied by the subjective qualities. So we know the shape of an object by color and feel. If you abstract the shape out and argue the colors and feels aren't real, then what status does our knowledge of the abstract shape have?
If you change "objective" to "scientifically validated" you have defined a position known as "ontological positivism", and I would say Dennett does subscribe to this.
The funny thing is, the school of thought which says consciousness is computation by our brains and any computer properly programmed can be conscious, a school known as "functionalism", itself gives ontological status to a non-corpreal abstract thing, namely computation.
If computation can be abstracted from not just the brain but any substrate at all then it exists. So computation can take place on an AMD chip and a Intel chip and a Turning Tape and anything you'd care to rigged up made out of anything whatsoever so long as it could represent the computation of a Turing Tape.
Existence is a tricky as a proposition, as Kant famously argued. Does the following make sense to you: the law of non-contradiction exists.
Computation has similar logical character as other rules of logic. In fact, intuitionism ensures a 1:1 correspondence between the two. So computation is not a "non-corporeal thing" any more than any other form of logic. If you take rules of logic to also be non-corporeal things, well then this "problem" you speak of was present in functionalism from the start, and yet it doesn't seem to trouble anyone.
Do mathematical things exist independently of the minds who conceive of them ? The ontological status of abstract things, right? My point is, materialists deny these kinds of things. That's disembodied spiritual bunkum and it has no place in modern thinking.
Then, later in the day they're perfectly happy to deal with things just as abstract and non-corpreal without feeling like they're cheating in any way.
The fact is the philosophy of science has not caught up to the advances in science as any good QM thread here will show.
>Does the law of non-contradiction exist?
The fact that neither of us can answer this (assuming we both agree to what it implies about the world, which actually, heh... I am not totally convinced of, but that's another matter) ... anyway the fact that neither us can answer this in the way you meant it is an interesting fact in the same family of interesting questions as raised in this discussion.
The quarks->atoms->molecules->neurons->brains->experience (consciouness) chain of causality, which is the standard model of reality and has been for a few hundred years now, is broken at both ends by which I mean the descriptive philosophical ideation at both ends is to no one's real satisfaction.
Sure, and they would have to provide some sort of naturalist account for mathematics. There are some proposals for this kicking around.
> is broken at both ends by which I mean the descriptive philosophical ideation at both ends is to no one's real satisfaction.
Indeed, there is no hole-free reduction along the chain you cite, but those holes are continuously shrinking. This is why I consider the special pleading around consciousness a god of the gaps. There are some very interesting puzzles around consciousness, but I think ascribing a special status to consciousness will ultimately be abandoned, just like vitalism.