>It just seems intuitively clear that an experience—say, a phenomenal presentation of neon green—is distinct from any physical state of your brain/body.
It's also "intuitively" clear to me that videos playing on my computer screen are distinct from registers moving electrons billions of times a second in my CPU. But literally everything else in the field of computer science stands against this "intuition." Likewise everything else in the cognitive sciences stands against this intuition, and I don't think there's any conceptual impossibility in designing a cognitive system that will think certain parts of its inner computation are distinct from other (or the same) parts of its inner computation.
>it seems utterly self-evident to the light of reason—that being round is not the same thing as being red
This is really just a statement about how you're prone to use the concepts "round" and "red." In reality, when we zoom in, we don't discover "roundness" in any particles, we discover probabilistic interactions between wave-particles that don't exactly have a size or shape; rather, approximate sizes and shapes are constructed out of various physical parameters we alter in interacting wave-particles we fire at them. Meaning, there is no undifferentiated thing "x" such that we can just say "x" has the property of being "round." And when we zoom in things aren't actually painted over by colors such that we can say an undifferentiated thing y has the property of being "red." There are much more complex stories that need to be told to develop an accurate model of properties like "roundness" and "redness," but the (meta)physics will probably not fall on manifest determinations based on a priori arguments or human concepts.
>These arguments start with an epistemic gap between the physical and the phenomenal
Knowledge and concepts are agent relative, so epistemic gaps aren't meaningful. There used to be an epistemic gap to many people between the morning star and evening star (and still is to people who have never heard this example), but they're both actually Venus. But wait, if we accept epistemic gap arguments then they're not both actually Venus. And wait, why do so many people say that people "used" to think they're not identical - if epistemic gaps entail metaphysical gaps then this could never happen.
>There does not seem to be a similar intelligible connection between physical brain activity and the occurrence of an experience, or the fact that we have a reddish rather than a greenish experience.
This is asserted with no argument and references an underspecified group of people to who this "seems" to. I imagine that it doesn't even seem like this to most philosophers, let alone people working in the cognitive sciences, let alone the people of the world or all people all throughout history.
>why doesn’t that processing go on “in the dark”?
Why can the clock on your CPU tick accurately enough to keep track of time even when not plugged into a power source, but you can't play Fortnite with the computer unplugged? Because of various design implementation details that are super complex.
>It’s conceivable that someone has physical profile P without being conscious, or while having experiences different from Matt’s actual experience—e.g., color inverted experiences.
It's also conceivable to play Fortnite without having it powered by a CPU - just imagine the movements on the monitor without a CPU. Have I just made a breakthrough discovery in the theory of computation?
>Or consider a China-body functional isomorph of Matt, where the people of China send radio signals to one another in ways that functionally duplicate the signaling patterns in Matt’s brain. Regardless of whether such systems would actually be conscious, it’s obviously coherently conceivable that such functional isomorphs exist without consciousness.
It's also conceivable to most people that you could never play Fortnite on a simple Turing machine - but Turing machines just are universal computers.
>But pain is essentially a feeling, so if there is a possible scenario where a brain state occurs without an associated feeling of pain, this is simply a possible scenario in which the brain state occurs without pain.
Winning the Battle Royale in Fortnite is essentially a network request between the last surviving player and the Fortnite server. Imagine a network request between the last surviving player and the Fortnite server (and make sure you do it ideally, where you imagine all the network infrastructure and classes in the code and physical particles moving around). Did you also realize after that imagining that that player would win the Battle Royale? Why not? Probably because you (and I) have no clue about any of the implementation details and how they relate to manifest situations like "winning the Battle Royale in Fortnite."
>Mary doesn’t know all the facts about human color vision. In particular, she doesn’t know what it’s like to see red.
She would know, just like if she knew all the computation facts she would be able to tell whenever someone wins a Battle Royale in Fortnite; but these implementation details are opaque to us so we can't imagine anything that would satisfy the prompt due to our epistemic ignorance.
>One-one: Identity is a one-to-one relation, not a one-many relation. You can’t be numerically identical to two distinct people.
These stipulations of "identity" are far too impoverished to cover the whole of what is possible in psychology. They rule out by stipulation that anybody could experience multiple personality disorder, when this is an empirical question.
>But it seems crazy to hold this view about your own identity over time. Imagine you are about to undergo an operation that will replace some large-ish fraction of your brain with new materials. Someone will wake up and live a happy life after the operation. Will it be you?
It will depend on the implementation details. You can just add an identity-inverter to your existing cognitive structure that will intercept every personal identity claim and you will believe that you are not yourself.
>If sense data theory is true, then physicalism is false.
Only if you a priori rule out the ability of virtualization or complex abstractions. Consider: If your computer has a recycling bin icon on the desktop but no recycling bin exists in your harddrive, our theory of computation is wrong.
>the “special composition question,” namely: if you’ve got two or more things, what would you have to do to them to get them to compose a further thing?
Things are useful abstractions, they're not units you add or substract absent your goals and interests. I don't even know what a fact of the matter would like here - either you can abstract some things successfully to suit your goals and interests or you can't. Much of philosophy is asking malformed and pointless questions.
>the concept of consciousness does not permit us to conceive of genuinely borderline cases of sentience, cases in which it is inherently indeterminate whether a creature is conscious: either a creature definitely is conscious or it is definitely not
Compare: this integer variable either has value 3 or it doesn't. This seems plausible until you're introducted to parallel computation, the "volatile" keyword or equivalents in programming languages, out of sync caches, etc.
>We know lots of stuff by rational intuition
Philosophers have a bad habit of positing rational faculties and divine senses. Why has no other field studying cognitive sciences - especially empirical ones - discovered these things? My bet is because they're just made up bullshit.
>the fact that our mental states are about things in the world, and have truth-conditions or satisfaction conditions
I don't think this is anything other that a grammatical reflection. Some people who speak English in our current timeframe are comfortable saying that mental experiences are "about" things. What stands or falls with this?
>Some experiences, like excruciating pain and euphoric pleasure, have “final” value or disvalue (i.e., they are good or bad, not just instrumentally, but in themselves).
There's no such thing as noninstrumental goodness or badness. Things are good or bad because they make others feel pleasure or pain. Just like how things are intrinsically tasty or intrinsically tall without reference to agents or environmental factors.
>I claim that even if we imagined the situation in arbitrary physical detail, it would still seem that nothing very bad is going on.
You shouldn't claim things like this without empirical evidence.
>The mind is indivisible.
This again rules out things like multiple personality disorder a priori, when obviously this would be adjudicated empirically.
Overall: Makes a lot of empirical claims from the armchair that aren't substantiated with empirical evidence, makes too many simplifying assumptions about our current state of knowledge about roundness and the mind that leads to malformed questions being asked and absurd answers within the malformed frame being posited, and doesn't engage with the bulk of work performed on the mind via psychology, neuroscience, or computer science. Verdict: Yep, it's analytic philosophy.
I kinda like the Fortnite analogy. Also I agree with you about identity, the mathematical way of speaking about identity doesn't seem to translate when talking about the self. In general a lot of these dualist arguments seem to me to rely on certain intuitions about phenomenological experience that I simply do not have.
Lots of great responses here. I too am frustrated by how much of the anti-physicalist position comes down to just asserting introspective intuitions, when no physicalist would be expected to think of those intuitions as particularly important. Why think I've evolved to represent my internal processes accurately? Certainly when *we* design products, that's not a high priority.
Thank you for laying this out in detail. I was thinking similar things while reading. In particular “There does not seem to be a similar intelligible connection between physical brain activity and the occurrence of an experience,” is maybe the worst case of begging the question I’ve ever seen.
I’ve felt similar things reading Bentham’s Self-Indication Assumption content—our consciousness is most likely to exist in a reality with an uncountably infinite number of consciousnesses, and that’s more likely with a God than not for… well it’s just obvious really! An exercise for the reader!
I've read about Mary's room a number of times, but it's become less convincing to me. When we imagine all of the physical facts about red being taught to Mary, it seems inconceivable that a "physical fact" could teach her what it's like to experience the color red. But this seems to just be a result of how our brains work.
If we give someone an exact description of what happens in their brain when they experience the color black, they can't force this experience to happen. They need to look at the color black to experience it, and for all of the physical things that cause the experience to occur. But if the brain had an extra region called the consciousness manipulator, which could mess around with the positions of every physical thing in the brain, it *could* force the experience of black to occur using knowledge of how it occurs. Similarly, if Mary had this region, teaching her every physical fact about red would allow her to experience it, even if her environment didn't initially contain a red object. And why allow our lack of this region to dictate whether or not something is a physical fact?
Maybe Mary dreams in colour, so has already experienced red in her dreams? (Assuming there's no developmental aspect where the red system doesn't develop until stimulated.)
The setup of the thought experiment seems designed to prevent this, but yes, this seems plausible. Color dreams might be natural rather than based on our experiences while awake. This is an even easier route towards the experience of red, but wouldn't defeat the argument because it relies wholly on the experience of a dream rather than physical facts about red.
If Mary knows every physical fact, she'd know what configuration her brain would be in while she experienced color dreams, or when she remembers (while awake) her somnolent color experiences. Thus she could figure out what it would look like when she steps outside. On the other hand, if you don't stipulate Mary knows what exactly her brain was doing while she dreamed/remembered, it's no longer clear the knowledge argument is going to work because you're no longer arguing for the independence of mental facts from the totality of physical facts.
I wrote this before finishing reading, and I have a terrible suspicion that this argument has already been written about. This seems like it happens a lot in philosophy. That, or I am very unoriginal.
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.
I don't have time today to look at all these arguments, but I do want to consider the first one: **distinctness intuition**.
Consider red light. It is light having a frequency within a specified range. This entirely physical.
Consider a light detector (digital camera, telescope, etc). Parts of this detector respond specifically to red light. This is entirely physical. When red light hits the detector, it physically creates electrical voltages.
The detector is physically connected to other physical devices which physically receive the detector's voltages and create other regions of electrical voltages (or local magnetic domains) to retain (remember/record/store) the detector's responses to light. Every part of this is entirely physical.
The storage regions are connected to other devices containing their own regions of voltages/magnetic domains which react to the stored detector information to create further versions or combinations of voltages/magnetic domains. This is called "data processing" and it is entirely physical.
Somewhere in all this purely physical activity, there will be a device (called a "screen" or a "display") that converts these processed electromagnetic signals into pretty pictures for humans to look at. This entire process is strictly physical.
When it comes to the human perception of the color red (or other things) we do not have the advantage of knowing how everything was physically arranged like we do for computers or digital cameras. But there is nothing about the human process that simply cannot be physical.
Regarding the human mind, we are currently like creatures who encounter electronic devices for the first time. It's reasonable to expect some of these creatures might resort to magical explanations for behaviors that we know are entirely physical.
The **distinctness intuition** bears a striking resemblance to "cargo cult".
It’s very interesting to me that so many of the arguments presented here hinge on taking certain propositions implied by physicalism and casting them as implausible or even obviously false, when many of those propositions are independently appealing to me apart from the question of whether physicalism is true. For example, one argument is that physicalism can’t explain commonsense beliefs about personal identity over time. But I think those commonsense views are bad anyway, so it’s appealing to me that physicalism also rules them out. Similarly, I’m glad physicalism rules out sense data theory, which I consider to be totally misguided even on the assumption that dualism is true. And of course I think it’s great that physicalism is incompatible with libertarian free will or the idea that consciousness is always determinant. Those are also two beliefs I see no reason to accept!
What I think this post really shows is that the question of dualism versus physicalism (versus idealism I guess) can’t be answered without stepping back and taking a broader look at our general approach to reality as a whole. I think the real divide here is already established at a much more basic level. Many of the most basic things dualism “gets you” are just totally uninteresting or even actively negative to me, but are clearly very appealing to others.
It seems that we can get algorithms - even relatively simple ones - to also have the "experience" of something. For instance, a reinforcement learning agent will treat its own reward function very differently from the reward function of another agent. This is similar to the way that people can feel their own pain, but not that of others.
Similarly, you can get AIs that have the "experience" of seeing a colour, even though they already "knew" everything there was to know about that colour:
Dualists seem convinced that dualism does successfully explain consciousness, but this case is incomplete. The dualist explanation, so far as I understand it, amounts to bare assertion: The soul explains consciousness because it is the kind of thing that by its very nature can be conscious.
I wouldn't really say that dualism "explains consciousness", but rather it takes it into account as a non-reducible feature of the world (also, in contrast to idealists, who think that only minds exist, dualists believe in physical phenomena, and in contrast to panpsychists, they don't think everything is conscious or that simple minds can be added up to form a more sophisticated mind). Furthermore, dualists argue that physicalists in principle cannot account for it in their worldview and thus are forced on pain of contradiction to deny the most obvious fact of our existence.
That's why it doesn't make sense to speak about "eliminative dualism", but there are people who identify themselves as eliminative materialists (in contemporary philosophy "materialism" has the same meaning as "physicalism").
I just don't see why one needs to be a dualist to take consciousness into account though. I consider myself a monist (I think there is only one kind of substance) and some of those substances are conscious and some are not (depending on my feelings towards panpsychism that day) Now I haven't "explained" how consciousness comes about, but as I said, neither does the dualist.
Re. "I wouldn't really say that dualism 'explains consciousness', but rather it takes it into account as a non-reducible feature of the world".
It would be more accurate to say that dualism *assumes* consciousness is a "non-reducible feature of the world". The phrase "takes into account" obscures the simple fact that we have no knowledge that consciousness exists independent of a physical mind, or is "non-reducible".
Re. "... dualists argue that physicalists in principle cannot account for it in their worldview..."
There is no principle that bars a physical account of consciousness. IN PRINCIPLE, consciousness can be considered recursive self-awareness.
Re. "... and thus [physicalists] are forced on pain of contradiction to deny the most obvious fact of our existence."
Not really, no. Sure the vocabulary we use when we talk about the mental (intentionality, belief, desire) is different than the vocabulary we use when we talk about the physical (size, distance, shape) but that doesn't really bother me. We use different vocabulary to talk about different things in different contexts all the time, nothing mysterious about it.
What I still want to see from Brian are arguments against idealism in favor of substance dualism. (Not that I'm entitled to anything of the sort!) He's mentioned idealism before in a video, but seemed to have difficulty challenging theistic idealism. Theistic idealism is much more readily compatible with Eastern than Western religions IMO, so it seems relevant to his worldview at least. After all, the distinction between man and God is not as easy to maintain if we are mental structures within the divine mind (contingent still perhaps, but how are we then not parts of God? How is it that atman=Brahmin at the deepest level of reality wouldn't hold necessarily true? How to square this with any form of Christianity?).
I don't think I have strong philosophical objections to theistic idealism, and I'm open to the view (at least if it can be developed in a Christianity-consistent way, though there are challenges here as you note). But even if theistic idealism is true, the relationship between my body and my consciousness will be structurally like what we have in dualism. The divine experiences that constitute my neural firing patterns won't constitute my reddish experience. Facts about my personal identity over time won't be grounded in whatever divine experiences constitute my body's physical continuity over time, etc.
Right, it doesn’t affect your anti-physicalists arguments for the most part. Still for me personally, I would say the odds of some form of vedanta are much higher under theistic idealism than Christianity. Ramanujian or Gaudiya vedanta seems especially promising to me since they also maintain the possibility of something akin to theosis (but that’s coming from an eastern orthodoxy perspective). I personally wish there was more comparative work here!
Although my personal understanding of the ontology of created things is a form of “structured participation mediated by logoi” influenced by St. Maximus which could plausibly be a form of theistic idealism I suppose.
In Vedanta mind is a material element, so technically, God doesn't have a mind. Brahman is consciousness. The avatars of God then can be seen as states of consciousness, or roles we play in the drama of life.
The distinction between man and God will depend on your flavour of Vedanta, but for Advaita, there is none. Brahman is nirguna or without distinction. But for all Vedanta we can say brahman = atman, but = expresses an identity claim, which doesn't require a strict one to one identity.
Every time I wonder whether it is necessary to state the physicalist case in more detail I get evidence that the sort of thinking I wish to challenge is still out there.
I was just wondering the extent to which the author is familiar with all the counter-arguments. The piece is written as though the rebuttals don't exist. That's a reasonable editorial choice, in terms of brevity, but some acknowledgement of the opposing views would be nice. I get the impression, perhaps unfairly, that the counter-arguments have not been deeply considered.
I'd be surprised if the author was unfamiliar with the objections to his position. But as you say, omitting them from this post was a reasonable decision.
The philosopher Christian List argues that Benj Hellie's vertiginous question, i.e. the question of why I'm me and not someone else, is evidence against physicalism.
Zombie Matt or inverted Matt are only possible creatures based on your understanding (and prejudices). You could simply be wrong.
I can envisage a system which requires no dualism, therefore equally, dualism is wrong.
Dualism implies a "soul-delivery system" and all such systems source their souls from an infinite supply, so your chance of finite incarnation is zero.
I really dislike the p-zombie argument. I cannot conceive of an exact copy of me down to the subatomic level that is not conscious. The fact that someone else can destroys conceivability arguments for me. They've decided that there's something beyond the physical, and I've decided there isn't. Introducing the p-zombie does nothing to argue either side because the argument only appeals to you based on your existing beliefs.
You have a point here. Thought experiments are often milked more than they can give - the fact that you can conceive of some never-observed combination of characteristics shows something about your conceptual mind and its ability to mash up concepts together, that doesn't necessarily say anything about what is possible in the real world. I'm surprised that philosophers often collapse this distinction.
Exactly. And anyway a p-zombie wouldn't truthfully be able to say he's aware, so he is distinguishable (by a reliable lie-detector [which I can envisage*]) so there's no such thing.
* a slightly effective one combined with enuf repetition to give a sufficient level of statistical confidence. (The other arguments here are a long way short of 100% certainty so we don't need to aim that high!)
The p-zombie is completely indistinguishable from a conscious observer in every way, though. Every possible measurement of the detector yields the same result, yet somehow the p-zombie is not conscious.
It's like saying every element of set A is an element of set B, and every element of set B is an element of set A, but they're somehow not the same set (because there's some mystical element missing from set A that you can't prove exists, but trust me, it's there).
OK a non-conscious observer might incorrectly think he's conscious. But being conscious is a thought process so is potentially detectable. But then does that thought process inevitably lead to consciousness?
Yes, you're right. I'm just moving the question up a level.
>I cannot conceive of an exact copy of me down to the subatomic level that is not conscious.
What about conceiving discovering that you exist while your body doesn't? Or that you come to a doctor and it turns that your skull is completely empty, would you conclude that you're not conscious after all?
>Introducing the p-zombie does nothing to argue either side because the argument only appeals to you based on your existing beliefs.
Well, it convinced me to become a dualist, so that's false.
>But being conscious is a thought process so is potentially detectable.
All particles and forces behave and are arranged exactly as if p-zombie were conscious, so it's not detectable in any way from a third person perspective.
>the fact that you can conceive of some never-observed combination of characteristics shows something about your conceptual mind and its ability to mash up concepts together, that doesn't necessarily say anything about what is possible in the real world.
Logical possibility =/= nomological (consistent with natural laws) possibility. And dualist arguments require only the first one.
"you come to a doctor and it turns that your skull is completely empty, would you conclude that you're not conscious after all?"
If you found a triangle with 4 sides...
You can't prove anything from a hypothetical instance.
But I agree (at least I think that was what you said!) that dualism adds a supernatural component. So everybody's position on it is perhaps just a reflection of how open they are to the supernatural.
I don't think you actually *can* imagine a physical thing that is about something else - like thoughts are... or a physical thing that isn't located in space - like thoughts aren't. So the dualist should simply vehemently reject your conceivability premise.
I'm just saying that whether or not you can invisage something has no bearing on whether or not that thing is real. As Arthur C. Clarke put it: "Any sufficiently advanced technology is indistinguishable from magic". IE: it can't be envisaged.
>It just seems intuitively clear that an experience—say, a phenomenal presentation of neon green—is distinct from any physical state of your brain/body.
It's also "intuitively" clear to me that videos playing on my computer screen are distinct from registers moving electrons billions of times a second in my CPU. But literally everything else in the field of computer science stands against this "intuition." Likewise everything else in the cognitive sciences stands against this intuition, and I don't think there's any conceptual impossibility in designing a cognitive system that will think certain parts of its inner computation are distinct from other (or the same) parts of its inner computation.
>it seems utterly self-evident to the light of reason—that being round is not the same thing as being red
This is really just a statement about how you're prone to use the concepts "round" and "red." In reality, when we zoom in, we don't discover "roundness" in any particles, we discover probabilistic interactions between wave-particles that don't exactly have a size or shape; rather, approximate sizes and shapes are constructed out of various physical parameters we alter in interacting wave-particles we fire at them. Meaning, there is no undifferentiated thing "x" such that we can just say "x" has the property of being "round." And when we zoom in things aren't actually painted over by colors such that we can say an undifferentiated thing y has the property of being "red." There are much more complex stories that need to be told to develop an accurate model of properties like "roundness" and "redness," but the (meta)physics will probably not fall on manifest determinations based on a priori arguments or human concepts.
>These arguments start with an epistemic gap between the physical and the phenomenal
Knowledge and concepts are agent relative, so epistemic gaps aren't meaningful. There used to be an epistemic gap to many people between the morning star and evening star (and still is to people who have never heard this example), but they're both actually Venus. But wait, if we accept epistemic gap arguments then they're not both actually Venus. And wait, why do so many people say that people "used" to think they're not identical - if epistemic gaps entail metaphysical gaps then this could never happen.
>There does not seem to be a similar intelligible connection between physical brain activity and the occurrence of an experience, or the fact that we have a reddish rather than a greenish experience.
This is asserted with no argument and references an underspecified group of people to who this "seems" to. I imagine that it doesn't even seem like this to most philosophers, let alone people working in the cognitive sciences, let alone the people of the world or all people all throughout history.
>why doesn’t that processing go on “in the dark”?
Why can the clock on your CPU tick accurately enough to keep track of time even when not plugged into a power source, but you can't play Fortnite with the computer unplugged? Because of various design implementation details that are super complex.
>It’s conceivable that someone has physical profile P without being conscious, or while having experiences different from Matt’s actual experience—e.g., color inverted experiences.
It's also conceivable to play Fortnite without having it powered by a CPU - just imagine the movements on the monitor without a CPU. Have I just made a breakthrough discovery in the theory of computation?
>Or consider a China-body functional isomorph of Matt, where the people of China send radio signals to one another in ways that functionally duplicate the signaling patterns in Matt’s brain. Regardless of whether such systems would actually be conscious, it’s obviously coherently conceivable that such functional isomorphs exist without consciousness.
It's also conceivable to most people that you could never play Fortnite on a simple Turing machine - but Turing machines just are universal computers.
>But pain is essentially a feeling, so if there is a possible scenario where a brain state occurs without an associated feeling of pain, this is simply a possible scenario in which the brain state occurs without pain.
Winning the Battle Royale in Fortnite is essentially a network request between the last surviving player and the Fortnite server. Imagine a network request between the last surviving player and the Fortnite server (and make sure you do it ideally, where you imagine all the network infrastructure and classes in the code and physical particles moving around). Did you also realize after that imagining that that player would win the Battle Royale? Why not? Probably because you (and I) have no clue about any of the implementation details and how they relate to manifest situations like "winning the Battle Royale in Fortnite."
>Mary doesn’t know all the facts about human color vision. In particular, she doesn’t know what it’s like to see red.
She would know, just like if she knew all the computation facts she would be able to tell whenever someone wins a Battle Royale in Fortnite; but these implementation details are opaque to us so we can't imagine anything that would satisfy the prompt due to our epistemic ignorance.
>One-one: Identity is a one-to-one relation, not a one-many relation. You can’t be numerically identical to two distinct people.
These stipulations of "identity" are far too impoverished to cover the whole of what is possible in psychology. They rule out by stipulation that anybody could experience multiple personality disorder, when this is an empirical question.
>But it seems crazy to hold this view about your own identity over time. Imagine you are about to undergo an operation that will replace some large-ish fraction of your brain with new materials. Someone will wake up and live a happy life after the operation. Will it be you?
It will depend on the implementation details. You can just add an identity-inverter to your existing cognitive structure that will intercept every personal identity claim and you will believe that you are not yourself.
>If sense data theory is true, then physicalism is false.
Only if you a priori rule out the ability of virtualization or complex abstractions. Consider: If your computer has a recycling bin icon on the desktop but no recycling bin exists in your harddrive, our theory of computation is wrong.
>the “special composition question,” namely: if you’ve got two or more things, what would you have to do to them to get them to compose a further thing?
Things are useful abstractions, they're not units you add or substract absent your goals and interests. I don't even know what a fact of the matter would like here - either you can abstract some things successfully to suit your goals and interests or you can't. Much of philosophy is asking malformed and pointless questions.
>the concept of consciousness does not permit us to conceive of genuinely borderline cases of sentience, cases in which it is inherently indeterminate whether a creature is conscious: either a creature definitely is conscious or it is definitely not
Compare: this integer variable either has value 3 or it doesn't. This seems plausible until you're introducted to parallel computation, the "volatile" keyword or equivalents in programming languages, out of sync caches, etc.
>We know lots of stuff by rational intuition
Philosophers have a bad habit of positing rational faculties and divine senses. Why has no other field studying cognitive sciences - especially empirical ones - discovered these things? My bet is because they're just made up bullshit.
>the fact that our mental states are about things in the world, and have truth-conditions or satisfaction conditions
I don't think this is anything other that a grammatical reflection. Some people who speak English in our current timeframe are comfortable saying that mental experiences are "about" things. What stands or falls with this?
>Some experiences, like excruciating pain and euphoric pleasure, have “final” value or disvalue (i.e., they are good or bad, not just instrumentally, but in themselves).
There's no such thing as noninstrumental goodness or badness. Things are good or bad because they make others feel pleasure or pain. Just like how things are intrinsically tasty or intrinsically tall without reference to agents or environmental factors.
>I claim that even if we imagined the situation in arbitrary physical detail, it would still seem that nothing very bad is going on.
You shouldn't claim things like this without empirical evidence.
>The mind is indivisible.
This again rules out things like multiple personality disorder a priori, when obviously this would be adjudicated empirically.
Overall: Makes a lot of empirical claims from the armchair that aren't substantiated with empirical evidence, makes too many simplifying assumptions about our current state of knowledge about roundness and the mind that leads to malformed questions being asked and absurd answers within the malformed frame being posited, and doesn't engage with the bulk of work performed on the mind via psychology, neuroscience, or computer science. Verdict: Yep, it's analytic philosophy.
I kinda like the Fortnite analogy. Also I agree with you about identity, the mathematical way of speaking about identity doesn't seem to translate when talking about the self. In general a lot of these dualist arguments seem to me to rely on certain intuitions about phenomenological experience that I simply do not have.
Bravo sir! 👏👏👏
Lots of great responses here. I too am frustrated by how much of the anti-physicalist position comes down to just asserting introspective intuitions, when no physicalist would be expected to think of those intuitions as particularly important. Why think I've evolved to represent my internal processes accurately? Certainly when *we* design products, that's not a high priority.
Thank you for laying this out in detail. I was thinking similar things while reading. In particular “There does not seem to be a similar intelligible connection between physical brain activity and the occurrence of an experience,” is maybe the worst case of begging the question I’ve ever seen.
I’ve felt similar things reading Bentham’s Self-Indication Assumption content—our consciousness is most likely to exist in a reality with an uncountably infinite number of consciousnesses, and that’s more likely with a God than not for… well it’s just obvious really! An exercise for the reader!
The world's best philosopher joins forces with the world's best philosophy blog! Thus begins the golden age.
There are so many good arguments against it, but Mary still reigns supreme!
Frank Jackson eventually became a physicalist.
Right, for astonishingly dumb reasons.
I've read about Mary's room a number of times, but it's become less convincing to me. When we imagine all of the physical facts about red being taught to Mary, it seems inconceivable that a "physical fact" could teach her what it's like to experience the color red. But this seems to just be a result of how our brains work.
If we give someone an exact description of what happens in their brain when they experience the color black, they can't force this experience to happen. They need to look at the color black to experience it, and for all of the physical things that cause the experience to occur. But if the brain had an extra region called the consciousness manipulator, which could mess around with the positions of every physical thing in the brain, it *could* force the experience of black to occur using knowledge of how it occurs. Similarly, if Mary had this region, teaching her every physical fact about red would allow her to experience it, even if her environment didn't initially contain a red object. And why allow our lack of this region to dictate whether or not something is a physical fact?
Maybe Mary dreams in colour, so has already experienced red in her dreams? (Assuming there's no developmental aspect where the red system doesn't develop until stimulated.)
The proposer of the argument can close the loophole but stipulating that she doesn't.
Yes, it was a hasty comment.
The setup of the thought experiment seems designed to prevent this, but yes, this seems plausible. Color dreams might be natural rather than based on our experiences while awake. This is an even easier route towards the experience of red, but wouldn't defeat the argument because it relies wholly on the experience of a dream rather than physical facts about red.
If Mary knows every physical fact, she'd know what configuration her brain would be in while she experienced color dreams, or when she remembers (while awake) her somnolent color experiences. Thus she could figure out what it would look like when she steps outside. On the other hand, if you don't stipulate Mary knows what exactly her brain was doing while she dreamed/remembered, it's no longer clear the knowledge argument is going to work because you're no longer arguing for the independence of mental facts from the totality of physical facts.
I wrote this before finishing reading, and I have a terrible suspicion that this argument has already been written about. This seems like it happens a lot in philosophy. That, or I am very unoriginal.
Yes, Paul Churchland has a paper on exactly this. It's titled "Knowing Qualia: A Reply to Jackson."
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.
I don't have time today to look at all these arguments, but I do want to consider the first one: **distinctness intuition**.
Consider red light. It is light having a frequency within a specified range. This entirely physical.
Consider a light detector (digital camera, telescope, etc). Parts of this detector respond specifically to red light. This is entirely physical. When red light hits the detector, it physically creates electrical voltages.
The detector is physically connected to other physical devices which physically receive the detector's voltages and create other regions of electrical voltages (or local magnetic domains) to retain (remember/record/store) the detector's responses to light. Every part of this is entirely physical.
The storage regions are connected to other devices containing their own regions of voltages/magnetic domains which react to the stored detector information to create further versions or combinations of voltages/magnetic domains. This is called "data processing" and it is entirely physical.
Somewhere in all this purely physical activity, there will be a device (called a "screen" or a "display") that converts these processed electromagnetic signals into pretty pictures for humans to look at. This entire process is strictly physical.
When it comes to the human perception of the color red (or other things) we do not have the advantage of knowing how everything was physically arranged like we do for computers or digital cameras. But there is nothing about the human process that simply cannot be physical.
Regarding the human mind, we are currently like creatures who encounter electronic devices for the first time. It's reasonable to expect some of these creatures might resort to magical explanations for behaviors that we know are entirely physical.
The **distinctness intuition** bears a striking resemblance to "cargo cult".
It’s very interesting to me that so many of the arguments presented here hinge on taking certain propositions implied by physicalism and casting them as implausible or even obviously false, when many of those propositions are independently appealing to me apart from the question of whether physicalism is true. For example, one argument is that physicalism can’t explain commonsense beliefs about personal identity over time. But I think those commonsense views are bad anyway, so it’s appealing to me that physicalism also rules them out. Similarly, I’m glad physicalism rules out sense data theory, which I consider to be totally misguided even on the assumption that dualism is true. And of course I think it’s great that physicalism is incompatible with libertarian free will or the idea that consciousness is always determinant. Those are also two beliefs I see no reason to accept!
What I think this post really shows is that the question of dualism versus physicalism (versus idealism I guess) can’t be answered without stepping back and taking a broader look at our general approach to reality as a whole. I think the real divide here is already established at a much more basic level. Many of the most basic things dualism “gets you” are just totally uninteresting or even actively negative to me, but are clearly very appealing to others.
It seems that we can get algorithms - even relatively simple ones - to also have the "experience" of something. For instance, a reinforcement learning agent will treat its own reward function very differently from the reward function of another agent. This is similar to the way that people can feel their own pain, but not that of others.
Similarly, you can get AIs that have the "experience" of seeing a colour, even though they already "knew" everything there was to know about that colour:
https://www.lesswrong.com/posts/DLmhJbuhYek5rEhpH/mairy-s-room-ai-reasoning-to-solve-philosophical-problems
Dualists seem convinced that dualism does successfully explain consciousness, but this case is incomplete. The dualist explanation, so far as I understand it, amounts to bare assertion: The soul explains consciousness because it is the kind of thing that by its very nature can be conscious.
I wouldn't really say that dualism "explains consciousness", but rather it takes it into account as a non-reducible feature of the world (also, in contrast to idealists, who think that only minds exist, dualists believe in physical phenomena, and in contrast to panpsychists, they don't think everything is conscious or that simple minds can be added up to form a more sophisticated mind). Furthermore, dualists argue that physicalists in principle cannot account for it in their worldview and thus are forced on pain of contradiction to deny the most obvious fact of our existence.
That's why it doesn't make sense to speak about "eliminative dualism", but there are people who identify themselves as eliminative materialists (in contemporary philosophy "materialism" has the same meaning as "physicalism").
I just don't see why one needs to be a dualist to take consciousness into account though. I consider myself a monist (I think there is only one kind of substance) and some of those substances are conscious and some are not (depending on my feelings towards panpsychism that day) Now I haven't "explained" how consciousness comes about, but as I said, neither does the dualist.
Re. "I wouldn't really say that dualism 'explains consciousness', but rather it takes it into account as a non-reducible feature of the world".
It would be more accurate to say that dualism *assumes* consciousness is a "non-reducible feature of the world". The phrase "takes into account" obscures the simple fact that we have no knowledge that consciousness exists independent of a physical mind, or is "non-reducible".
Re. "... dualists argue that physicalists in principle cannot account for it in their worldview..."
There is no principle that bars a physical account of consciousness. IN PRINCIPLE, consciousness can be considered recursive self-awareness.
Re. "... and thus [physicalists] are forced on pain of contradiction to deny the most obvious fact of our existence."
Not really.
So do you believe in dualism of mental and physical properties?
Not really, no. Sure the vocabulary we use when we talk about the mental (intentionality, belief, desire) is different than the vocabulary we use when we talk about the physical (size, distance, shape) but that doesn't really bother me. We use different vocabulary to talk about different things in different contexts all the time, nothing mysterious about it.
What's supposed to be mysterious about dualism?
Well I'm just saying it's unnecessary.
What I still want to see from Brian are arguments against idealism in favor of substance dualism. (Not that I'm entitled to anything of the sort!) He's mentioned idealism before in a video, but seemed to have difficulty challenging theistic idealism. Theistic idealism is much more readily compatible with Eastern than Western religions IMO, so it seems relevant to his worldview at least. After all, the distinction between man and God is not as easy to maintain if we are mental structures within the divine mind (contingent still perhaps, but how are we then not parts of God? How is it that atman=Brahmin at the deepest level of reality wouldn't hold necessarily true? How to square this with any form of Christianity?).
I don't think I have strong philosophical objections to theistic idealism, and I'm open to the view (at least if it can be developed in a Christianity-consistent way, though there are challenges here as you note). But even if theistic idealism is true, the relationship between my body and my consciousness will be structurally like what we have in dualism. The divine experiences that constitute my neural firing patterns won't constitute my reddish experience. Facts about my personal identity over time won't be grounded in whatever divine experiences constitute my body's physical continuity over time, etc.
Right, it doesn’t affect your anti-physicalists arguments for the most part. Still for me personally, I would say the odds of some form of vedanta are much higher under theistic idealism than Christianity. Ramanujian or Gaudiya vedanta seems especially promising to me since they also maintain the possibility of something akin to theosis (but that’s coming from an eastern orthodoxy perspective). I personally wish there was more comparative work here!
Although my personal understanding of the ontology of created things is a form of “structured participation mediated by logoi” influenced by St. Maximus which could plausibly be a form of theistic idealism I suppose.
Thanks for the response!
In Vedanta mind is a material element, so technically, God doesn't have a mind. Brahman is consciousness. The avatars of God then can be seen as states of consciousness, or roles we play in the drama of life.
The distinction between man and God will depend on your flavour of Vedanta, but for Advaita, there is none. Brahman is nirguna or without distinction. But for all Vedanta we can say brahman = atman, but = expresses an identity claim, which doesn't require a strict one to one identity.
Pro physicalist argument tier list too please?
Every time I wonder whether it is necessary to state the physicalist case in more detail I get evidence that the sort of thinking I wish to challenge is still out there.
Nice post, but can you provide the rebuttals?
There are rebuttals in the comments. Anti-physicalism is essentially "supernaturalism" and shares most of the flaws of appeals to the supernatural.
I am familiar with most of the rebuttals.
I was just wondering the extent to which the author is familiar with all the counter-arguments. The piece is written as though the rebuttals don't exist. That's a reasonable editorial choice, in terms of brevity, but some acknowledgement of the opposing views would be nice. I get the impression, perhaps unfairly, that the counter-arguments have not been deeply considered.
I'd be surprised if the author was unfamiliar with the objections to his position. But as you say, omitting them from this post was a reasonable decision.
Infinite Small = infinitely smaller than string theory, that’s for sure - the consciousness
Argument Existing Together - Top to Bottom Anti-Physicalist Strength
Inconceivability Argument - Everything We Can’t Conceive
Conceivability Argument - Everything We Can Conceived
Nihilism / Universalism - Infinite-Layered Soul - Infinite Small
Personal Identity Argument - Infinite-Layered Soul - Infinite Small
Certainty Allegedly Argument - Deconstruction to Infinite Small Process
Divisibility - Finding Infinite Small Process
Knowledge Argument - Finding Infinite Small For Real - All Sensors Discovered To Find Infinite Small
Sensory Quality Argument - Sensing Matter for Infinite Small
Mereological Nilhilism - One-Layered Soul - Infinite Small
Epistemic Argument - Mental Sentence - Abstract/Mental
Immateriality of Intellect - Mental Of Knowing Gives Reality - Mental
The Distictless Intuition - Intuitive - Thinking Matter Sensor - Mental
Rational Insight - Thinking Matter Sensor - Mental
Intentionally - Thinking Matter Sensor + Programmed - Mental
Axiological - Different Body/Different Experience - Mental
Determinacy - 4D & Beyond Reality
Free Will - 3D Reality
Made this in 30 mins - Probs needs massive adjustment & improvement
Conceiveable Theory - They all convienceable arguements - in different layers of reality- Physicism to Soul - I think
The philosopher Christian List argues that Benj Hellie's vertiginous question, i.e. the question of why I'm me and not someone else, is evidence against physicalism.
https://en.wikipedia.org/wiki/Vertiginous_question
https://philpapers.org/rec/LISTFA
Zombie Matt or inverted Matt are only possible creatures based on your understanding (and prejudices). You could simply be wrong.
I can envisage a system which requires no dualism, therefore equally, dualism is wrong.
Dualism implies a "soul-delivery system" and all such systems source their souls from an infinite supply, so your chance of finite incarnation is zero.
(Of course it could be a single soul reused...)
I really dislike the p-zombie argument. I cannot conceive of an exact copy of me down to the subatomic level that is not conscious. The fact that someone else can destroys conceivability arguments for me. They've decided that there's something beyond the physical, and I've decided there isn't. Introducing the p-zombie does nothing to argue either side because the argument only appeals to you based on your existing beliefs.
You have a point here. Thought experiments are often milked more than they can give - the fact that you can conceive of some never-observed combination of characteristics shows something about your conceptual mind and its ability to mash up concepts together, that doesn't necessarily say anything about what is possible in the real world. I'm surprised that philosophers often collapse this distinction.
Exactly. And anyway a p-zombie wouldn't truthfully be able to say he's aware, so he is distinguishable (by a reliable lie-detector [which I can envisage*]) so there's no such thing.
* a slightly effective one combined with enuf repetition to give a sufficient level of statistical confidence. (The other arguments here are a long way short of 100% certainty so we don't need to aim that high!)
The p-zombie is completely indistinguishable from a conscious observer in every way, though. Every possible measurement of the detector yields the same result, yet somehow the p-zombie is not conscious.
It's like saying every element of set A is an element of set B, and every element of set B is an element of set A, but they're somehow not the same set (because there's some mystical element missing from set A that you can't prove exists, but trust me, it's there).
OK a non-conscious observer might incorrectly think he's conscious. But being conscious is a thought process so is potentially detectable. But then does that thought process inevitably lead to consciousness?
Yes, you're right. I'm just moving the question up a level.
>I cannot conceive of an exact copy of me down to the subatomic level that is not conscious.
What about conceiving discovering that you exist while your body doesn't? Or that you come to a doctor and it turns that your skull is completely empty, would you conclude that you're not conscious after all?
>Introducing the p-zombie does nothing to argue either side because the argument only appeals to you based on your existing beliefs.
Well, it convinced me to become a dualist, so that's false.
>But being conscious is a thought process so is potentially detectable.
All particles and forces behave and are arranged exactly as if p-zombie were conscious, so it's not detectable in any way from a third person perspective.
>the fact that you can conceive of some never-observed combination of characteristics shows something about your conceptual mind and its ability to mash up concepts together, that doesn't necessarily say anything about what is possible in the real world.
Logical possibility =/= nomological (consistent with natural laws) possibility. And dualist arguments require only the first one.
"you come to a doctor and it turns that your skull is completely empty, would you conclude that you're not conscious after all?"
If you found a triangle with 4 sides...
You can't prove anything from a hypothetical instance.
But I agree (at least I think that was what you said!) that dualism adds a supernatural component. So everybody's position on it is perhaps just a reflection of how open they are to the supernatural.
I don't think you actually *can* imagine a physical thing that is about something else - like thoughts are... or a physical thing that isn't located in space - like thoughts aren't. So the dualist should simply vehemently reject your conceivability premise.
I'm just saying that whether or not you can invisage something has no bearing on whether or not that thing is real. As Arthur C. Clarke put it: "Any sufficiently advanced technology is indistinguishable from magic". IE: it can't be envisaged.
The impossibility of imagining square circles has nothing to do with impossibility of them existing in the actual world?
Circles are non-square by definition so that's trivially impossible.
I would say the same thing about identity of mental phenomena and physical phenomena. Trivially impossible.
But it's equally trivially impossible for a supernatural entity to exchange information with one tied to the laws of physics/causality.
But impossible = magic so it may just be "sufficiently advanced technology".
Not so long ago living things were assumed to contain "vital force" to make them alive. We no longer need that cos we understand the chemistry.