This model in your brain is what we typically call the physical knowledge about the bowl.
No, it’s what we usually call a percept. “Physical model” usually refers to something outside the head, like a set of equations on a blackboard, or a computer model.
Now let’s compare this to the physical knowledge A could gain about B’s brain processes and the associated ‘subjective’ experience. If A were to look at an MRI scan of B’s brain, A would form an abstraction of B’s brain that is simply an image. This abstraction would, of course, not do justice to the complexity of the processes in B’s brain. It could possibly be stored on a floppy disk. In order to know all the physical knowledge about B’s brain processes, A would have to form an accurate abstraction. This much harder for a brain than for a bowl, because brain processes have many more details that we care about.If A were to actually form an abstraction of Bob’s brain that captures the aspects that matter, Alice would have to run nearly every aspect of it in her own brain.
You have compressed together two different claims—the claim that Alice needs detailed and complete information about Bob’s brain, and the claim that she needs to hold it in her own head.
The original Knowledge (Mary’s Room) argument starts form the assumption that 3rd-person (stored externally to the brain) knowledge is sufficient for most things in science. The idea that there is a special class of things which require 1st-person instantiation introduces a dualism. The idea that all science is subjective and 1st-person is just wrong.
Physicalists sometimes respond to Mary’s Room by saying that one can not expect Mary actually to actually instantiate Red herself just by looking at a brain scan. It seems obvious to then that a physical description of brain state won’t convey what that state is like, because it doesn’t put you into that state. As an argument for physicalism, the strategy is to accept that qualia exist, but argue that they present no unexpected behaviour, or other difficulties for physicalism.
That is correct as stated but somewhat misleading: the problem is why is it necessary, in the case of experience, and only in the case of experience to instantiate it in order to fully understand it. Obviously, it is true a that a descirption of a brain state won’t put you into that brain state. But that doesn’t show that there is nothing unusual about qualia. The problem is that there in no other case does it seem necessary to instantiate a brain state in order to undertstand something.
If another version of Mary were shut up to learn everything about, say, nuclear fusion, the question “would she actually know about nuclear fusion” could only be answered “yes, of course....didn’t you just say she knows everything”? The idea that she would have to instantiate a fusion reaction within her own body in order to understand fusion is quite counterintuitive. Similarly, a description of photosynthesis will make you photosynthesise, and would not be needed for a complete understanding of photosynthesis.
There seem to be some edge cases.: for instance, would an alternative Mary know everything about heart attacks without having one herself? Well, she would know everything except what a heart attack feels like, and what it feels like is a quale. the edge cases, like that one, are cases are just cases where an element of knowledge-by-acquaintance is needed for complete knowledge. Even other mental phenomena don’t suffer from this peculiarity. Thoughts and memories are straightforwardly expressible in words, so long as they don’t involve qualia.
So: is the response “well, she has never actually instantiated colour vision in her own brain” one that lays to rest and the challenge posed by the Knowledge argument, leaving physicalism undisturbed? The fact that these physicalists feel it would be in some way necessary to instantiate colour, but not other things, like photosynthesis or fusion, means they subscribe to the idea that there is something epistemically unique about qualia/experience, even if they resist the idea that qualia are metaphysically unique.
Is the assumption of epistemological uniqueness to be expected given physicalism? Some argue that no matter how much you know about something “from the outside”, you quite naturally wouldn’t be expected to understand it from the inside. That’s a common intuition, as shown by the frequency of rhetoric along the lines of “you wouldn’t know, you weren’t there”. We will go on to argue that Being There is not strictly compatible with physicalism.
Instantiation/representation/having a model, in my view, is not binary and is needed for any understanding. You seem to say that I don’t think ‘understanding’ requires instantiation. My example with the bowl is meant to say that you do require a non-zero degree of instantiation—although I would call it modelling instead because instantiation makes me think of a temporal model, but bowls can be represented as static without losing their defining features. In short, no model=no understanding is my claim. This is an attempt to make the word knowledge more precise because it can mean many things.
I then go on to describe why you need a more high fidelity model to represent the defining features of someone’s brain state evolving over some time period. The human brain is obviously incapable of that. Although an exact subatomic model of a bowl contains a lot of information too, you can abstract much more of it away without losing anything essential.
I’d also like to correct that I make no claims that science, or anything, is subjective. Conversely, I’m claiming that subjectivity is not a fundamental concept and we can taboo it in discussions like these.
There seem to be some edge cases.: for instance, would an alternative Mary know everything about heart attacks without having one herself? Well, she would know everything except what a heart attack feels like, and what it feels like is a quale.
It might be new information, it might be the same information presented in a different way. But the latter is still not something implied by physics...physics doesn’t suggest that different modes of presentation, or irreducibly subjective perspectives should exist.
The new information would be which nerves correspond to the heart (which is more than most need to know about heart attacks), and how they respond to that situation. I’m not positing irreducibility, I just haven’t seen research conclusively wrapping up how to measure pain objectively yet.
No, it’s what we usually call a percept. “Physical model” usually refers to something outside the head, like a set of equations on a blackboard, or a computer model.
You have compressed together two different claims—the claim that Alice needs detailed and complete information about Bob’s brain, and the claim that she needs to hold it in her own head.
The original Knowledge (Mary’s Room) argument starts form the assumption that 3rd-person (stored externally to the brain) knowledge is sufficient for most things in science. The idea that there is a special class of things which require 1st-person instantiation introduces a dualism. The idea that all science is subjective and 1st-person is just wrong.
Physicalists sometimes respond to Mary’s Room by saying that one can not expect Mary actually to actually instantiate Red herself just by looking at a brain scan. It seems obvious to then that a physical description of brain state won’t convey what that state is like, because it doesn’t put you into that state. As an argument for physicalism, the strategy is to accept that qualia exist, but argue that they present no unexpected behaviour, or other difficulties for physicalism.
That is correct as stated but somewhat misleading: the problem is why is it necessary, in the case of experience, and only in the case of experience to instantiate it in order to fully understand it. Obviously, it is true a that a descirption of a brain state won’t put you into that brain state. But that doesn’t show that there is nothing unusual about qualia. The problem is that there in no other case does it seem necessary to instantiate a brain state in order to undertstand something.
If another version of Mary were shut up to learn everything about, say, nuclear fusion, the question “would she actually know about nuclear fusion” could only be answered “yes, of course....didn’t you just say she knows everything”? The idea that she would have to instantiate a fusion reaction within her own body in order to understand fusion is quite counterintuitive. Similarly, a description of photosynthesis will make you photosynthesise, and would not be needed for a complete understanding of photosynthesis.
There seem to be some edge cases.: for instance, would an alternative Mary know everything about heart attacks without having one herself? Well, she would know everything except what a heart attack feels like, and what it feels like is a quale. the edge cases, like that one, are cases are just cases where an element of knowledge-by-acquaintance is needed for complete knowledge. Even other mental phenomena don’t suffer from this peculiarity. Thoughts and memories are straightforwardly expressible in words, so long as they don’t involve qualia.
So: is the response “well, she has never actually instantiated colour vision in her own brain” one that lays to rest and the challenge posed by the Knowledge argument, leaving physicalism undisturbed? The fact that these physicalists feel it would be in some way necessary to instantiate colour, but not other things, like photosynthesis or fusion, means they subscribe to the idea that there is something epistemically unique about qualia/experience, even if they resist the idea that qualia are metaphysically unique.
Is the assumption of epistemological uniqueness to be expected given physicalism? Some argue that no matter how much you know about something “from the outside”, you quite naturally wouldn’t be expected to understand it from the inside. That’s a common intuition, as shown by the frequency of rhetoric along the lines of “you wouldn’t know, you weren’t there”. We will go on to argue that Being There is not strictly compatible with physicalism.
Late response:
Instantiation/representation/having a model, in my view, is not binary and is needed for any understanding. You seem to say that I don’t think ‘understanding’ requires instantiation. My example with the bowl is meant to say that you do require a non-zero degree of instantiation—although I would call it modelling instead because instantiation makes me think of a temporal model, but bowls can be represented as static without losing their defining features. In short, no model=no understanding is my claim. This is an attempt to make the word knowledge more precise because it can mean many things.
I then go on to describe why you need a more high fidelity model to represent the defining features of someone’s brain state evolving over some time period. The human brain is obviously incapable of that. Although an exact subatomic model of a bowl contains a lot of information too, you can abstract much more of it away without losing anything essential.
I’d also like to correct that I make no claims that science, or anything, is subjective. Conversely, I’m claiming that subjectivity is not a fundamental concept and we can taboo it in discussions like these.
The crucial question is whether the model needs to be inside-the-head in some or all cases.
I don’t see the usefulness of tabooing subjectivity when it is the whole point.
Where else would the model be if not inside the head? Or are you saying one can ‘understand’ physical objects without any hint of a model?
To quote myself:
Gotcha, I’m referring to a representation encoded in neuron activity, which is the physical process.
On the other hand, would someone who has a heart attack know as much as Mary about what’s going on?
Would Mary learn any new information over the course of a heart attack?
It might be new information, it might be the same information presented in a different way. But the latter is still not something implied by physics...physics doesn’t suggest that different modes of presentation, or irreducibly subjective perspectives should exist.
The new information would be which nerves correspond to the heart (which is more than most need to know about heart attacks), and how they respond to that situation. I’m not positing irreducibility, I just haven’t seen research conclusively wrapping up how to measure pain objectively yet.