See section 2 on Conciousness, and in particular the Mary problem.
As Colin McGinn has stated, "Consciousness defies explanation in [compositional, spatial] terms. Consciousness does not seem to be made up out of smaller spatial processes.... Our faculties bias us towards understanding matter in motion, but it is precisely this kind of understanding that is inapplicable to the mind-body problem."
Nonsense. What is computer software? Can you explain it? How can you copy it without creating new matter or energy? It's information, that's why. Our thoughts are information, the product of physicalism and caused by it. Nothing inherently mysterious, though it might appear so to the human mind that is actually experiencing it. The mind-body duality dilema that people struggle with is analogous to an optical illusion - e.g. the hollow mask that appears solid, or the wire cube that flips orientation - as with these it's difficult to think in our mind of both states simultaneously. We can flip states, but we can't 'see' or imagine both simultaneously. In a similar way we can (almost) imagine computer software as information, but have greater difficulty imagining this condition when applying it to our own thoughts. It becomes even more confusing, and more like the attempt to simultaneously 'see' both states of an optical illusion, when we try an imagine what's happening when we think about what we are thinking now in the first person; and some explanations of conciousness and dualism confuse the issue by trying to do this.
Did Mary (see site) learn something new about pain? Yes. She physically experienced (both in terms of physical neurological responses and informational interpretation) the real pain for which she had only previously had a physical neurological model. Her model has simply been updated with real first hand experiential data, when previously the only experiential data she had was neurological mapping of things she had already experienced. In practice of course this 'schrodingers's cat' type of thought experiment is limited. The definition of the experiment is incorrect. Pain is simply a more intense stimulus of corresponding stimuli - presumably Mary hadn't been denide the sense of touch, otherwise she would have had difficulty relating to much of the theoretical information she had read in the first place. What sort of human would have emerged from the room if that had been the case. It's a hypethetical case where the accuracy of the perceived consequences are dubious, to the extent that the conclusion does not necessarily follow. Mary can't even pick up the bowling ball if she's been deprived of the appropriate senses!
"Given that it is exceedingly difficult and seemingly impossible to provide a compositional, spatial analysis of the intrinsic nature of an event such as an experience of pain, can a metaphysical naturalist reasonably promise us some other kind of explanation of its nature?"
This is metaphysical mumbo-jumbo. "compositional, spatial analysis of the intrinsic nature of an event" - does this actually mean anything? These arguments are often dressed up in these phrases that some researcher has latched onto or invented to describe some concept that is difficult to understand - fair enough. But then the problem is that these phrases are used in ways that make it difficult to grasp what is being said.
"...can he (physicalist) at least provide a plausible explanation of how it came about that the universe contains occurrences such as experiences of pain and pleasure? We doubt it."
Why, when it has expressly been given? The dualist is confusing a simple causal relationship between an excessive physical stimulus and the informational model that the receiving organism experiences as a result, as a separate entity.
How does a human feel pain? A cat? A worm? A bacterium? A cell? A complex molecule? A grain of sand? Physicaly, they don't, they simply react - either extremely passivily according to relatively simple laws of physics for a grain of sand, or in more complex physical/chemical ways for a molecule, or in increasingly more complex chemical/exlectrical/biological/neurological ways for higher organisms.
Being organsims with a complex nervous system that includes the brain we have adapted ourselves to the interpretation of our environment. One of our interpretations is to feel/think/experience our environment in terms of our own experiences. The more animate and the more similar to us other entities are, the more easly we make this mapping - we anthropomorphise or personify. We do this with ourselves and our 'thoughts' to the greatest degree. Some of us even have to create, or imagine, or to model non-existant entities using the same principle - demons, faires, ghosts, gods, etc. Sometimes our brains get it wrong - they extrapolate (a very valuable tool used in the prediction process) - they extrapolate too much, they become gullible, seeing optical illusions, even delusions.
"What, then, is the theistic alternative? Theism begins by acknowledging that experiences of pleasure and pain and choices are events that occur in subjects which refer to themselves by the first-person pronoun 'I.'"
Do some of the lower organsims not feel pain? If they do, do they refer to themselves in the first person? Again, when is this magical dualism switched on - just humans, apes, ...? Be careful, else you'll be dragging up biblical nonsense again.
"As the theist René Descartes wrote...(quotes Descartes)..."
The dualist is here acknowledging the simplicity of the mind in one respect, but denying it from the physicalist respect, which itself is very simple.
Decartes: "I cannot distinguish in myself any parts" - could that be because there is nothing to distinguish? Is Decartes referring to the distinction between mind and body, or the distinction between parts of his thoughts? Is he struggling to identify his thoughts as distinct physical entities? Maybe he's struggling because they don't exist as such. When my computer is running some software I can see the results on screen, I can imaging the electrons moving at amazing speeds around the silicon based microscopic circuitry, and I can imaging the source code I have written if it's my program that's running - but can I imaging the actual 'software' itself as a physical entity? No more than I can be self aware and imagine my own thoughts as something distict from my physicality.
I can certainly imagine what the dualists are describing. I can imaging some ghostly substance that might be my soul, spirit, thoughts - but that's all it is, an imagined concept. I have no reason to think it exists. When movies portray a dead soul rising out of a body - is that what we really think is happeng in some invisible dimension? Of course not (or maybe you do). But there is no evidence to support that imagining, that concept. I can imagine flying pigs, with little wings - do they exist? Because I can imagine something doesn't mean it exists.
I can imagine God, angels - all with typically anthropomorphised representations. If God really exists with some of the real properties he's supposed to have, such as omniscience, can I imagine that? Only in a limited way, as I imagine the mathematical concept of infinity - something bigger than anything, but to which if I add more it is the same thing? Does that sound a little like the ontological argument for God? Figments of our limited imaginations!
In postulating the concept of dualism we are using a limited capacity tool (the mind) to grasp something of itself that is merely apparent. We accept illusions, hoaxes, some delusions, for what they are - the mind not presenting a sufficiently good approximation of the external physical reality - but then for no apparent reason than the mystery of not underestaning something, we invent dualism, supernatural external agents, theism. Figments of our limited imaginations.
Why is it so difficult to see that the alternative - the physical causal relationship between neurological activity and the resulting mental models?
Don't be fooled by the apparent complexity. How can this proposed simple process take part in this argument, including those parts of the process that produce the written (typed) work above (whether you think its good or not it's still apparently complex). But, just as the many many simple little steps of evolution have produced us, so the many many simple little processes in this organism have produced this. If I had omnisciently and omnipotently flashed out all this text instantly, in zero time, then we might be closer to the realisation of what God is. But I didn't. Every impulse to my fingers to type, every nuerologocal action that contributes, is very very simple - they are simply working very fast and in great numbers. The sophisticaion comes from the co-ordination. But co-ordinated lesser orgaisms that are independent to some extent also produce similarly amazing results. Bees building honey combs, ants foreging for food - they are all sophisticated co-ordinated processes where the individual elements are all amazingly simple whan compared with the result.
We are at the top of the chain, as far as we know, in this evolutionary scale, so we find it difficult to imagine anything that might be more complex than ourselves that is not some ultimate God.
Dualism, as with God, is a failed attempt to come to terms with the complex. We can imagine the simple. We can imagine somethings more complex. But eventually, as complexity increases we lose touch and make a giant leap to something bigger, but conceptually easier to identify - even if not easier to understand.
In maths, imagine a simple sum: 1 + 1 = 2. Now imagine some complex formula - say some series using powers and factorials - still with me? Now try some complex differential equations - still here? Now Schrödinger equation... - have you seen them and do you understand them? By now some, if not most of us (including me) has lost track of these equations - they are more complex than I am familar with. I can imagine some vague representation on a physicists blackboard, employing symbols I'm not familar with - it's all Greek to me. Now, let's imagine infinity - got that?
I bet more people with upper high school and graduate level maths find it easier to grasp the notion of infinity than they do some complex expression representing something in physics. It's quite straight forward to imagine clearly some simpler things, and relatively easy to grasp something of the notion of a concept that is very extensive, in size, number, power, infomational capacity, than it is to imagine some things that are just more complex than we are used to. It's easier to imagine God as represented by some very vague notions of extreme extension to simpler human properties, than it is to imagine in detail more complex processes or organisms than those with which we are currently familar.
Dualism is similar to some extent. We find it difficult to imagine where the boundary lies - or how the continuum flows - from the physical bodies that we have come to be familiar with and the thoughts that we are also familiar with. Because we can't imagine this we invent a separation - dualism. It's a failure of our current capacity to understand.
So, are physicalists so advanced that they can conceive of it, while the poor dumb dualists can't? No, of course not. What is most likely at work here is an ingrained view that's difficult to shake off. I would guess, though I have nothing to support this, that all physicalists have had dualist interpretations at one time - simply because it is easier to imagine.
This is an imagination gap. If the gap is narrow we can build a bridge easily. If the gap is wide we prefer to fly across, skipping whatever is missing. Go from what we are familiar with to some extreme concept based on the familar properties. It's difficult to imagine what we don't know. This imagination gap should be familar to most students, particularly the more advanced your studies*. You can read the fear of the apparent consequences in the writings of theists. We are dealing with a 'duality of the gaps' that is similar to the 'God of the gaps'.
"we are not arguing that there is some gap in an otherwise seamless naturalist view of reality"
Oh yes you are.
"This is an argument from the fundamental character of reality and what kinds of things exist (purposes, feelings..."
Yes, purpose and feelings exist, but not as some distinct dualist entity. They are properties of the organism that is experiencing. Particularly feelings and emotions - simple hormonal biological chemical electrical reactions. 'Purpose' is apparent, not real in the sense that is independent free-will.
The only dualism I see in all this is that in the mind of the dualist. On the one had an imagination failure in not seeing the continuum and inclusiveness of physicalism that encompases conciousness, and on the other, the runaway imagination that goes in leaps and bounds from missing data regarding conciousness, to mind-body dualism, on to basic theism, and then on to all the wild imaginings of heaven, hell, saints, miracles, etc.
*I remember very clearly the earliest experience of this, on a very limited scale. In primary school I could do 'short-division' but I couldn't fathom out 'long-division' - it was very frustrating, and even frightening - I feared I was really dumb!. Then a neigbour's son, a year older than me, spent some time going through examples. I remember very clearly when the penny dropped. A spiritual revalation? Later, at university I struggled with some concepts of advanced chemistry - it was an electronics course and I naively hadn't expected to be learning chemistry and I'd skipped chemistry at highschool, so I was ill equiped for some of this stuff. I remember the anguish in class, seeing all the other students nodding knowingly while I was thinking "what the hell is he talking about". Recognising the response I went off to the library and made sure I caught up. Never be afraid of what you don't know! If you need to know it, put in sufficient effort so that your brain and its neurological patterns become famialar with it - eventually you'll see the light - alleluiah!