Nice post. I tend to think that solipsism of the sort you describe (a form of “subjective idealism”) ends up looking almost like regular materialism, just phrased in a different ontology. That’s because you still have to predict all the things you observe, and in theory, you’d presumably converge on similar “physical laws” to describe how things you observe change as a materialist does. For example, you’ll still have your own idealist form of quantum mechanics to explain the observations you make as a quantum physicist (if you are a quantum physicist). In practice you don’t have the computing power to by yourself figure all these things out just based on your own observations, but presumably an AIXI version of you would be able to deduce the full laws of physics from just these solipsist observations.
So if the laws of physics are the same, the only difference seems to be that in the case of idealism, we call the ontological primitive “mental”, and we say that external phenomena don’t actually exist but instead we just model them as if they existed to predict experiences. I suppose this is a consistent view and isn’t that different in complexity from regular materialism. I just don’t see much motivation for it. It seems slightly more elegant to just assume that all the stuff we’re modeling as if it existed actually does exist (whatever that means).
And I’m not sure how much difference it makes to postulate that the ontological primitive is “mental” (whatever that means). Whether the ontological primitive is mental or not, there are still mechanical processes in our brains that cause us to believe we’re conscious and to ask why there’s a hard problem of consciousness. Maybe that already explains all the data, and there’s no need for us to actually be conscious (whatever that would mean).
Anyway, I find these questions to be some of the most difficult in philosophy, because it’s so hard to know what we’re even talking about. We have to explain the datum that we’re conscious, but what exactly does that datum look like? It seems that how we interpret the datum depends on what ontology we’re already assuming. A materialist interprets the datum as saying that we physically believe that we’re conscious, and materialism can explain that just fine. A non-materialist insists that there’s more to the datum than that.
In the case of idealism, we call the ontological primitive “mental”, and we say that external phenomena don’t actually exist but instead we just model them as if they existed to predict experiences. I suppose this is a consistent view and isn’t that different in complexity from regular materialism.
I can’t disagree. This definitely shifts my thinking a bit. I think that solipsism + structured observations might be comparable in complexity to materialism + an ability for qualia to arise from material phenomena. But at that point the questions hinges a bit on what we think is spookier. I’m convinced that a material solution to the hard problem of consciousness is spooky. I think I could maybe be convinced that hallucinating structured observations might be similarly spooky.
And I think you’re right about the problem of knowing what we’re talking about.
Makes sense. :) To me it seems relatively plausible that the intuition of spookiness regarding materialist consciousness is just a cognitive mistake, similar to Capgras syndrome. I’m more inclined to believe this than to adopt weirder-seeming ontologies.
I think it’s all evidence, and the delusion is part of the materialist explanation of that evidence. Analogously, part of the atheist hypothesis has to be an explanation of why so many cultures developed religions.
That said, as we discussed, there’s debate over what the nature of the evidence is and whether delusions in the materialist brains of us zombies can adequately explain it.
And “fossils were created by the Devil to mislead us” is part of the theist explanation of creationism. The thing is, that rationalists have complete contempt for this kind of argument in some contexts...but rationalists also believe that rationality is based on normative rules. If “don’t dismiss evidence as delusory” is a rule, it has to apply to everybody. And it it isn’t, it has to apply to nobody.
I wouldn’t support a “don’t dismiss evidence as delusory” rule. Indeed, there are some obvious delusions in the world, as well as optical illusions and such. I think the reason to have more credence in materialism than theist creationism is the relative prior probabilities of the two hypotheses: materialism is a lot simpler and seems less ad hoc. (That said, materialism can organically suggest some creationism-like scenarios, such as the simulation hypothesis.)
Ultimately the choice of what hypothesis seems simpler and less ad hoc is up to an individual to decide, as a “matter of faith”. There’s no getting around the need to start with bedrock assumptions.
A major problem with physicalist dismissal of experiential evidence (as I’ve discussed previously) is that the conventional case for believing in physics is that it explains experiential evidence, e.g. experimental results. Solomonoff induction, among the best formalizations of Occam’s razor, believes in “my observations”.
If basic facts like “I have observations” are being doubted, then any case for belief in physics has to go through something independent of its explanations of experiential evidence. This looks to be a difficult problem.
You could potentially resolve the problem by saying that only some observations, such as those of mechanical measuring devices, count; however, this still leads to an analogous problem to the hard problem of consciousness, namely, what is the mapping between physics and the outputs of the mechanical measuring devices that are being explained by theories? (The same problem comes up of “what data is the theorizing trying to explain” whether the theorizing happens in a single brain or in a distributed intelligence, e.g. a collection of people using the scientific method)
If basic facts like “I have observations” are being doubted, then any case for belief in physics has to go through something independent of its explanations of experiential evidence. This looks to be a difficult problem
There are significant differences between observations in the sense of pointer positions, and qualia.
You could potentially resolve the problem by saying that only some observations, such as those of mechanical measuring devices, count; however, this still leads to an analogous problem to the hard problem of consciousness, namely, what is the mapping between physics and the outputs of the mechanical measuring devices that are being explained by theories?
OK, but then you have parted company with the strong program in rationalism, the idea that all rational agents should be able to converge on objective truth.
I have “faith” in things like Occam’s razor and hope it helps get toward objective truth, but there’s no way to know for sure. Without constraints on the prior, we can’t say much of anything beyond the data we have.
choosing an appropriate algorithm requires making assumptions about the kinds of target functions the algorithm is being used for. With no assumptions, no “meta-algorithm”, such as the scientific method, performs better than random choice.
For example, without an assumption that nature is regular, a million observations of the sun having risen on past days would tell us nothing about whether it will rise again tomorrow.
My comment about Occam’s razor was in reply to “the idea that all rational agents should be able to converge on objective truth.” I was pointing out that even if you agree on the data, you still may not agree on the conclusions if you have different priors. But yes, you’re right that you may not agree on how to characterize the data either.
Nice post. I tend to think that solipsism of the sort you describe (a form of “subjective idealism”) ends up looking almost like regular materialism, just phrased in a different ontology. That’s because you still have to predict all the things you observe, and in theory, you’d presumably converge on similar “physical laws” to describe how things you observe change as a materialist does.
Which is to say that idealistic instrumentalism is as complex as materialistic instrumentalism. The complexity of the minimum ruleset you need to predict observation is the same in each case. But that doesn’t mean the complexity of materialist ontology is the same as the complexity of idealist ontology. Idealism asserts that mentality, or some aspect of it, is fundamental , whereas materialism says that is all a complex mechanism. So idealism is asserting a simpler ontology. Which itslef is pretty orthogonal to the question how much complexity you need to predict observation. (of course, the same confusion infects discussions of the relative complexity of different interpretations of quantum mechanics).
Anyway, I find these questions to be some of the most difficult in philosophy, because it’s so hard to know what we’re even talking about. We have to explain the datum that we’re conscious, but what exactly does that datum look like? It seems that how we interpret the datum depends on what ontology we’re already assuming. A materialist interprets the datum as saying that we physically believe that we’re conscious, and materialism can explain that just fine. A non-materialist insists that there’s more to the datum than that.
Yes. It’s hard to agree what evidence is, meaning that is hard to do philosophy, and impossible to do philosophy algorithmically.
Nice post. I tend to think that solipsism of the sort you describe (a form of “subjective idealism”) ends up looking almost like regular materialism, just phrased in a different ontology. That’s because you still have to predict all the things you observe, and in theory, you’d presumably converge on similar “physical laws” to describe how things you observe change as a materialist does. For example, you’ll still have your own idealist form of quantum mechanics to explain the observations you make as a quantum physicist (if you are a quantum physicist). In practice you don’t have the computing power to by yourself figure all these things out just based on your own observations, but presumably an AIXI version of you would be able to deduce the full laws of physics from just these solipsist observations.
So if the laws of physics are the same, the only difference seems to be that in the case of idealism, we call the ontological primitive “mental”, and we say that external phenomena don’t actually exist but instead we just model them as if they existed to predict experiences. I suppose this is a consistent view and isn’t that different in complexity from regular materialism. I just don’t see much motivation for it. It seems slightly more elegant to just assume that all the stuff we’re modeling as if it existed actually does exist (whatever that means).
And I’m not sure how much difference it makes to postulate that the ontological primitive is “mental” (whatever that means). Whether the ontological primitive is mental or not, there are still mechanical processes in our brains that cause us to believe we’re conscious and to ask why there’s a hard problem of consciousness. Maybe that already explains all the data, and there’s no need for us to actually be conscious (whatever that would mean).
Anyway, I find these questions to be some of the most difficult in philosophy, because it’s so hard to know what we’re even talking about. We have to explain the datum that we’re conscious, but what exactly does that datum look like? It seems that how we interpret the datum depends on what ontology we’re already assuming. A materialist interprets the datum as saying that we physically believe that we’re conscious, and materialism can explain that just fine. A non-materialist insists that there’s more to the datum than that.
Great comment. Thanks.
I can’t disagree. This definitely shifts my thinking a bit. I think that solipsism + structured observations might be comparable in complexity to materialism + an ability for qualia to arise from material phenomena. But at that point the questions hinges a bit on what we think is spookier. I’m convinced that a material solution to the hard problem of consciousness is spooky. I think I could maybe be convinced that hallucinating structured observations might be similarly spooky.
And I think you’re right about the problem of knowing what we’re talking about.
Makes sense. :) To me it seems relatively plausible that the intuition of spookiness regarding materialist consciousness is just a cognitive mistake, similar to Capgras syndrome. I’m more inclined to believe this than to adopt weirder-seeming ontologies.
So evidence contrary to materialism isn’t evidence, it’s a delusion.
I think it’s all evidence, and the delusion is part of the materialist explanation of that evidence. Analogously, part of the atheist hypothesis has to be an explanation of why so many cultures developed religions.
That said, as we discussed, there’s debate over what the nature of the evidence is and whether delusions in the materialist brains of us zombies can adequately explain it.
And “fossils were created by the Devil to mislead us” is part of the theist explanation of creationism. The thing is, that rationalists have complete contempt for this kind of argument in some contexts...but rationalists also believe that rationality is based on normative rules. If “don’t dismiss evidence as delusory” is a rule, it has to apply to everybody. And it it isn’t, it has to apply to nobody.
I wouldn’t support a “don’t dismiss evidence as delusory” rule. Indeed, there are some obvious delusions in the world, as well as optical illusions and such. I think the reason to have more credence in materialism than theist creationism is the relative prior probabilities of the two hypotheses: materialism is a lot simpler and seems less ad hoc. (That said, materialism can organically suggest some creationism-like scenarios, such as the simulation hypothesis.)
Ultimately the choice of what hypothesis seems simpler and less ad hoc is up to an individual to decide, as a “matter of faith”. There’s no getting around the need to start with bedrock assumptions.
A major problem with physicalist dismissal of experiential evidence (as I’ve discussed previously) is that the conventional case for believing in physics is that it explains experiential evidence, e.g. experimental results. Solomonoff induction, among the best formalizations of Occam’s razor, believes in “my observations”.
If basic facts like “I have observations” are being doubted, then any case for belief in physics has to go through something independent of its explanations of experiential evidence. This looks to be a difficult problem.
You could potentially resolve the problem by saying that only some observations, such as those of mechanical measuring devices, count; however, this still leads to an analogous problem to the hard problem of consciousness, namely, what is the mapping between physics and the outputs of the mechanical measuring devices that are being explained by theories? (The same problem comes up of “what data is the theorizing trying to explain” whether the theorizing happens in a single brain or in a distributed intelligence, e.g. a collection of people using the scientific method)
There are significant differences between observations in the sense of pointer positions, and qualia.
That’s much more like the easy problem.
OK, but then you have parted company with the strong program in rationalism, the idea that all rational agents should be able to converge on objective truth.
I have “faith” in things like Occam’s razor and hope it helps get toward objective truth, but there’s no way to know for sure. Without constraints on the prior, we can’t say much of anything beyond the data we have.
https://en.wikipedia.org/wiki/No_free_lunch_theorem#Implications_for_computing_and_for_the_scientific_method
For example, without an assumption that nature is regular, a million observations of the sun having risen on past days would tell us nothing about whether it will rise again tomorrow.
Occam’s razor tells you to find the simplest explanation for the evidence,so it is downstream of the question of what constitutes evidence.
My comment about Occam’s razor was in reply to “the idea that all rational agents should be able to converge on objective truth.” I was pointing out that even if you agree on the data, you still may not agree on the conclusions if you have different priors. But yes, you’re right that you may not agree on how to characterize the data either.
Which is to say that idealistic instrumentalism is as complex as materialistic instrumentalism. The complexity of the minimum ruleset you need to predict observation is the same in each case. But that doesn’t mean the complexity of materialist ontology is the same as the complexity of idealist ontology. Idealism asserts that mentality, or some aspect of it, is fundamental , whereas materialism says that is all a complex mechanism. So idealism is asserting a simpler ontology. Which itslef is pretty orthogonal to the question how much complexity you need to predict observation. (of course, the same confusion infects discussions of the relative complexity of different interpretations of quantum mechanics).
Yes. It’s hard to agree what evidence is, meaning that is hard to do philosophy, and impossible to do philosophy algorithmically.