Happy to see someone else defending non-materialism since I see it as underrated. Some thoughts:
Nah, it can't account for what an "observation" is so can't really explain observations
This is really the heart of the issue. Is an observation qualia or some purely material process in our brain?
I should adopt the explanation that best explains my observation
Seems like a distraction? If the observations are materialist than materialism can explain the materialist-myness; if they are qualatic that we need qualia to define the qualiatic-myness. Merely knowing qualia have a property of my-ness doesn't tell us which type. And it would seem unusual to say, know that myness is qualiatic without first knowing observations are qualiatic, since we can't directly experience our myness, only our observations.
It has to do some ontological reshuffling around what "observations" are that, I think, undermines the case for believing in physics in the first place, which is that it explains my observations
Why does it undermine physics?
I think it makes more sense to think of mental things as existing subjectively (i.e. if they belong to you) and physical things as existing objectively. I definitely think that dualism is making a mistake in thinking of objectively-existing mental things
This relates quite closely to my post on Relabellings vs. External References. If mental things are just a relabelling of materialism, they don't actually add anything be being present in the model. In order to actually change the system, they need to refer to external entities, in which case mental things aren't really subjective any more.
Why does it undermine physics?
Say I don't believe in physics and you're trying to get me to believe in physics. What sort of evidence can you show me? The most obvious is to do some experiments so I can see the results. Without this I wouldn't have (epistemic, normative) reason to believe in physics.
The case for believing in physics needs to talk about all of (a) the thing causing experimental results, (b) the experimental results, (c) the epistemic process that, upon seeing (b), should believe in (a).
If someone said "actually, there's no such thing as (c), there's just (a) and (b)", then that's going to be hard to argue for, epistemically/normatively, since there is a denial of the existence of epistemology.
If the observations are materialist than materialism can explain the materialist-myness; if they are qualatic that we need qualia to define the qualiatic-myness.
Whether "my observations" are qualia or materialist, they're still deictic; I get stuff from my eyes but not your eyes.
As long as the norm for explanations is that they're supposed to explain these, the explanation has to say e.g. why these observations are coming from my eyes and not yours (or, indeed, from an inanimate object like a rock).
The most "view-from-nowhere" way of doing this is anthropics, which still needs to talk about mental entities (observers).
Trying to say something like "there is just the wave function, there are no observers" is insufficient for predicting these data; you need additional posits (e.g. Born rule, e.g. functionalism to define what an observer is).
I am not really importantly distinguishing qualia-observations from "the data my cognitive process is trying to explain" here. It seems like even an account that somehow doesn't believe in qualia still needs to have data that it explains, hence running into similar issues.
If someone said "actually, there's no such thing as (c), there's just (a) and (b)", then that's going to be hard to argue for, epistemically/normatively, since there is a denial of the existence of epistemology.
Physics can explain the epistemic component in your brain - it just can't explain the experience of believing or cognition in general.
I am not really importantly distinguishing qualia-observations from "the data my cognitive process is trying to explain" here. It seems like even an account that somehow doesn't believe in qualia still needs to have data that it explains, hence running into similar issues.
The data to be explained are the experiences - say of seeing red or feeling pain. If you take that data to be the red brain process, that can be explained purely materialistically. The red brain process only needs a materialistic observer - ie. some kind of central processing unit - what's wrong with this? It's only qualia that needs the observer to have a non-materialistic component.
Physics can explain the epistemic component in your brain
Physics can't say what an epistemic component is. Physics says what particle configurations have more amplitude given a starting state. You can define a bridge law that says "epistemic component = this particle configuration". But that's you doing the bridging, not physics. In doing this bridging you are doing cognition about mental processes ("epistemic components"). You'd have to derive/justify/etc whatever theory you're using for the bridging by relating the mental to the physical.
If you take that data to be the red brain process, that can be explained purely materialistically.
This justificatory chain is not well-founded. Saying "my observations = brain processes" only makes sense if I can conceptualize physics and believe in it (otherwise, how do I know what a brain process is or think it is identical with my observations?). So as a justification for physics, it's circular.
Here's a brief statement of my position. "Why believe in physics? Because it explains observations. Whose observations? Those of whoever is considering believing in physics." Epistemically, these observations can't be considered "already-physical", that's assuming the conclusion.
Physics can't say what an epistemic component is
Insofar as the epistemic component consists of logic, physics can't say what that logic is ontologically. On the other hand, it can describe how brain states are linked to physical states, which should be sufficient to explain materialistic-observations.
So as a justification for physics, it's circular
Circularity is inevitable (I like the arguments in Where Recursive Justification Hits Bottom), so this isn't as problematic as it seems.
That said, I agree that starting with subjective experience as our initial foundations is in one sense more empirical than starting with the external world as we can derive the external world's existence from patterns in subjective experience.
Physics can’t say what an epistemic component is.
Physics doesn't say what shoppingcentres are..there a difference between being unable to solve a problem in principle , and leaving details to be filled in.
Epistemically, these observations can’t be considered “already-physical”, that’s assuming the conclusion
You also shouldn't assume they are non physical. In fact, observers and observations can be treated in a neutral way that doesn't beg any metaphysical questions.
Jessica: We’re now talking about the sensation of the flavor of the chocolate though. Is this really that different from talking about “that car over there”? I don’t see how some entities can, in a principled way, be classified as objective and some as subjective
Consider the Mary's room argument. If you know everything objective about a car, you know everything about it. But Mary knows everything objective about your brain without knowing how red looks to you.
Like, in talking about “X” I’m porting something in my mental world-representation into the discursive space
Distinguish cloning and referring:-
When you talk about "how chocolate tastes to Rocko",you are referring to how chocolate tastes to Rocko, but you are not instantiating his neural patterns in your brain ,so you don't know how chocolate tastes to him.
Reference is very far from complete knowledge. To use the computer analogy, a reference (pointer,key, handle etc) allows you to access sn object,but doesn't tell you everything about it -- you still have to query it. A reference is generally the minimum amount of information that distinguishes one entity from another.
Jessica: Okay, I agree with this sort of mental/outside-mental distinction, and you can define subjective/objective to mean that.
Or you can use effable/ineffable , or "requires personal instantiation".
discrete runs on top of continuous
Could well be the other way round. General relativity could be a continuous approximation to a discrete theory.
choice runs on top of causality
It's not clear that physicalists need a strong account of choice.
I recently had a Twitter conversation with Roko Mijic. I believe it contains ideas that a wider philosophical/rationalist audience may find valuable, and so include here a transcript (quoted with permission).
Jessica: There are a number of "runs on top of" relations in physicalism:
My present philosophy inverts the metaphysical order: mind/discrete/choice is more basic.
This is less of a problem than it first appears, because mind/discrete/choice can conceptualize, hypothesize, and learn about body/continuous/causality, and believe in a "effectively runs on" relation between the two.
In contrast, starting from body/continuous/causality has trouble with getting to mind/discrete/choice as even being conceptualizable, hence tending towards eliminativism.
Roko: Eliminitivism has a good track record though.
Jessica: Nah, it can't account for what an "observation" is so can't really explain observations.
Roko: I don't really see a problem here. It makes perfect sense within a reductionist or eliminativist paradigm for a robot to have some sensors and to sense its environment. You don't need a soul, or god, or strong free will, or objective person-independent values for that.
Jessica: Subjective Occam's razor (incl. Solomonoff induction) says I should adopt the explanation that best explains my observations. Eliminativism can't really say what "my" means here. If it believed in "my observations" it would believe in consciousness.
It has to do some ontological reshuffling around what "observations" are that, I think, undermines the case for believing in physics in the first place, which is that it explains my observations.
Roko: It means the observations that are caused by sensors plugged into the hardware that your algorithm instance is running on.
Jessica: That means "my algorithm instance" exists. Sounds like a mental entity. Can't really have those under eliminativism (but can under functionalism etc).
Roko: I don't want to eliminate my mental instance from my philosophy, that would be kind of ridiculous.
Jessica: Well, yes, so eliminativism is false. I understand eliminativism to mean there is only physical, no mental. Believing mental runs on physical could be functionalism, property dualism, or some other non-eliminativist position.
Roko: I think it makes more sense to think of mental things as existing subjectively (i.e. if they belong to you) and physical things as existing objectively. I definitely think that dualism is making a mistake in thinking of objectively-existing mental things
Jessica: I don't think this objective/subjective dichotomy works out. I haven't seen a good positive case, and my understanding of deixis leads me to believe that references to the objective must be resolved subjectively. See also On the Origin of Objects.
Basically I don't see how we can, in a principled way, have judgments like "X exists but only subjectively, not objectively". It would appear that by saying "X exists" I am asserting that X is an existent object (i.e. I'm saying something objective).
See also Thomas Nagel's The View From Nowhere. Spoiler alert: there isn't a view from nowhere, it's an untenable concept.
Roko: My sensation of the flavor of chocolate exists but only subjectively.
Jessica: We're now talking about the sensation of the flavor of the chocolate though. Is this really that different from talking about "that car over there"? I don't see how some entities can, in a principled way, be classified as objective and some as subjective.
Like, in talking about "X" I'm porting something in my mental world-representation into the discursive space. I don't at all see how to classify some of these portings as objective and some as subjective.
See also writing on the difficulty of the fact/opinion distinction.
Roko: It's not actually the flavor "of" the chocolate though. It's the sensation of flavor that your brain generates for you only, in response to certain nerve stimuli.
I don't see how some entities can, in a principled way, be classified as objective and some as subjective.
It's very easy actually. Subjectives are the things that you cannot possibly be mistaken about, the "I think therefore I am's".
No deceiving demon can fool you into thinking that you're experiencing the taste of chocolate, the color purple, or an orgasm. No deceiving demon can fool you into thinking that you're visualizing the number 4.
Jessica: I don't think this is right. The thought follows the experience. There can be mistranslations along the way. This might seem like a pedantic point but we're talking about linguistic subjective statements so it's relevant.
Translating the subjective into words can introduce errors. It's at least as hard as, say, adding small numbers. So your definition means "1+1=2" is also subjective.
Roko: I think that it's reasonable to see small number math instances as subjectives. I can see 3 pens. I can conceive of 3 dots, that's a subjective thing. It's in the same class as seeing red or smelling a rose.
[continuing from the deceiving demon thread] These are the things that are inherently part of your instance or mind. The objective, on the other hand, is always somewhat uncertain and inferred. Things are out there and they send signals to you. But you are inferring their existence.
Jessica: Okay, I agree with this sort of mental/outside-mental distinction, and you can define subjective/objective to mean that. This certainly doesn't bring in other connotations of the objective, such as view-from-nowhere or observer-independence; I can be wrong about indexicals too.
Roko: Well it happens to be a property of our world that when different people infer the shape of the objective (i.e. draw maps), they always converge. This is what being in a shared reality means.
I mean they always converge if they follow the right principles, e.g. complexity priors, and those same principles are the ones that allow us to successfully manipulate reality via actions. That's what the objective world out there is.
Jessica: Two reasons they could converge:
I'm fine with calling 1 observer-independent. Problem: your view of, and references to, 2, depend on your standpoint. Because of deixis.
Obvious deictic references are things like "the car over there" or "the room I'm in". It is non-obvious but, I think, true, that all physical references are deictic. Which makes sense because physical causality is deictic (locally causal and symmetric).
Even "the Great Wall of China" refers to the Great Wall of China on our Earth. It couldn't refer to the one on the twin Earth. And the people on twin Earth have "the Great Wall of China" refer to the one on the twin Earth, not ours.
At the same time, maps created starting from different places can be patched together, in a collage. However, pasting these together requires taking into account the standpoint-dependence of the individual maps being pasted together.
And at no point does this pasting-together result in a view from nowhere. It might seem that way because it keeps getting bigger and more zoomed-out. But at each individual time it's finite.
Roko: Yes this is all nice but I think the point where we get to hard questions is when we think about mental phenomena that I would classify as subjectives as being part of the objective reality.
This is the petrl.org problem, or @reducesuffering worrying about whether plankton or insects "really do" have subjective experiences etc
Jessica: In my view "my observation" is an extremely deictic reference, to something maximally here-and-now, such that there isn't any stabilization to do. Intermediate maps paste these extremely deictic maps together into less-deictic, but still deictic, maps. It never gets non-deictic.
It's hard to pin down intersubjectively precisely because it's so deictic. I can't really port my here-and-now to your here-and-now without difficulty.