What Mary Didn't Know (1986) [pdf](courses.physics.illinois.edu)
courses.physics.illinois.edu
What Mary Didn't Know (1986) [pdf]
https://courses.physics.illinois.edu/phys419/sp2021/Jackson1986_WhatMaryDidntKnow.pdf
61 comments
> This whole thought experiment is actually presenting what is quite possibly a limitation specific to human minds - no reason to extrapolate to all possible minds. That is, human minds seem to have two very distinct ways of altering their internal state.
How to define “mind”? If all human minds turn out to have a certain property, how do we decide whether that property is essential or accidental to “being a mind”? Obviously if the property is “being human”, it can’t be essential to the property of “being a mind” (unless someone wants to claim that only humans can have minds by definition-a claim very few would make). But, if the property is “having two very distinct ways of altering their internal state”, how do we know if that is just an accidental property that all human minds happen to have, but non-human minds might lack, or an essential property of being a mind, which all minds must have to be “a mind”?
How to define “mind”? If all human minds turn out to have a certain property, how do we decide whether that property is essential or accidental to “being a mind”? Obviously if the property is “being human”, it can’t be essential to the property of “being a mind” (unless someone wants to claim that only humans can have minds by definition-a claim very few would make). But, if the property is “having two very distinct ways of altering their internal state”, how do we know if that is just an accidental property that all human minds happen to have, but non-human minds might lack, or an essential property of being a mind, which all minds must have to be “a mind”?
Sure - I'm not claiming to have settled the theory of mind!
I'm just pointing out that nothing in the argument about Mary, even if we accept that she would learn something new when leaving the room, proves that qualia must be non-physical or non-computational or anything like that.
You could find arguments that such a separation between qualia and physical facts is indeed necessary for any mind that could really exist in the world. But they would have to be other arguments - this one doesn't work.
I'm just pointing out that nothing in the argument about Mary, even if we accept that she would learn something new when leaving the room, proves that qualia must be non-physical or non-computational or anything like that.
You could find arguments that such a separation between qualia and physical facts is indeed necessary for any mind that could really exist in the world. But they would have to be other arguments - this one doesn't work.
I think a version of this argument does succeed in showing that qualia are real as opposed to just some conceptual mistake.
The problem with arguing about whether qualia are “physical” or “non-physical”, is I’m not sure how much sense such a distinction makes if one is not a Cartesian dualist-which I’m not, and you don’t appear to be either
The problem with arguing about whether qualia are “physical” or “non-physical”, is I’m not sure how much sense such a distinction makes if one is not a Cartesian dualist-which I’m not, and you don’t appear to be either
Personally, I'm of the opinion that the human/animal mind is a computational process happening in the brain, and that a sufficiently complex computer could also "run" such a mind. In that sense, I believe they are entirely physical objects, just as much as the Linux kernel running on my phone is a physical object.
As such, I believe that qualia are just how we would label some aspects of this computation, and I believe that concepts like a p-zombie are thus more or less non-sensical.
I'm not claiming to know for sure that this is the way. I do think it's, at least in principle, possible that a mind is a different thing, one that our understanding of physics can't (yet?) fully model. Hell, even though I'm an atheist, I wouldn't even claim that the concept of a divine soul is completely impossible.
As such, I believe that qualia are just how we would label some aspects of this computation, and I believe that concepts like a p-zombie are thus more or less non-sensical.
I'm not claiming to know for sure that this is the way. I do think it's, at least in principle, possible that a mind is a different thing, one that our understanding of physics can't (yet?) fully model. Hell, even though I'm an atheist, I wouldn't even claim that the concept of a divine soul is completely impossible.
Is it humans or computers with a limitation?
A single celled organism lacks any sensory perception and so, from its perspective, it has explored the depths of the universe without having to ever even move. With each step upwards in complexity, the entire perceivable domain becomes wider. That humans can experience a facsimile of something and the "reality" of something differently, would seem to imply that we have a more sophisticated input system than something that would equate the two different "inputs."
A single celled organism lacks any sensory perception and so, from its perspective, it has explored the depths of the universe without having to ever even move. With each step upwards in complexity, the entire perceivable domain becomes wider. That humans can experience a facsimile of something and the "reality" of something differently, would seem to imply that we have a more sophisticated input system than something that would equate the two different "inputs."
> A single celled organism lacks any sensory perception and so, from its perspective, it has explored the depths of the universe without having to ever even move.
Single celled organisms do have a kind of sensory perception and can react to changes in their environment. Even our own individual cells have this ability (and I'm not talking about neurons, I'm talking about every single cell in our body, or at least the vast majority).
In fact, some single celled organisms (or at least, colonies of them) have even been proven to be capable of certain computations - for example, "slime mould", which is a bacterial colony, can grow in a way which finds solutions to simple mazes.
> That humans can experience a facsimile of something and the "reality" of something differently
That's not what I was talking about. I'm saying that we have no way to directly stimulate our sensory organs with with signals that mimic external stimulus, which would be quite trivial for an electronic brain. Also, I'm saying our memory of direct sensory experience (what I saw when I looked at a red thing) is separate from our memory of more conceptual subjects (what is the square root of 4, who conquered England from Normandy, what I ate this morning).
While it may turn out that this "architecture" is necessary for having consciousness/a mind, it doesn't seem a priori impossible to build an electronic mind that doesn't have these limitations/separations.
Single celled organisms do have a kind of sensory perception and can react to changes in their environment. Even our own individual cells have this ability (and I'm not talking about neurons, I'm talking about every single cell in our body, or at least the vast majority).
In fact, some single celled organisms (or at least, colonies of them) have even been proven to be capable of certain computations - for example, "slime mould", which is a bacterial colony, can grow in a way which finds solutions to simple mazes.
> That humans can experience a facsimile of something and the "reality" of something differently
That's not what I was talking about. I'm saying that we have no way to directly stimulate our sensory organs with with signals that mimic external stimulus, which would be quite trivial for an electronic brain. Also, I'm saying our memory of direct sensory experience (what I saw when I looked at a red thing) is separate from our memory of more conceptual subjects (what is the square root of 4, who conquered England from Normandy, what I ate this morning).
While it may turn out that this "architecture" is necessary for having consciousness/a mind, it doesn't seem a priori impossible to build an electronic mind that doesn't have these limitations/separations.
Not sure I follow the original premise. If Mary knows everything there is to know in physics, then Mary knows about the wave theory of light and the colour spectrum. She may not have experienced the colour red but she is aware of the concept of the colour red.
Additionally, while Mary may only receive information in black and white, she perceives in full colour and can see the colours of her own skin and clothes.
The combination of the first and second facts means that Mary can conceive what it would be like to see the colour red before she ever sees it. The first time she sees green she will know that she has perceived some colour, even if she gets the label wrong and calls it red for instance.
Additionally, while Mary may only receive information in black and white, she perceives in full colour and can see the colours of her own skin and clothes.
The combination of the first and second facts means that Mary can conceive what it would be like to see the colour red before she ever sees it. The first time she sees green she will know that she has perceived some colour, even if she gets the label wrong and calls it red for instance.
The point of the thought experiment is to ask if Mary would interpret the experience of seeing the specific color with her own eyes as a new experience. If yes, and given the premise that she knows everything that it is possible to know about the physics of color and the human brain, the conclusion is supposed to be that an experience is not a physical fact of the world.
I have written another comment on why I think this conclusion is wrong.
I have written another comment on why I think this conclusion is wrong.
> The conclusion is supposed to be that an experience is not a physical fact of the world.
I see what you're getting at and mostly agree (hence the Upvote!). But...
Whether a 1st person qualitative experience is a "physical fact of the world" depends on your level of description. In a sense, it's not an epistemically objective physical fact that I can share with others. However, it is just a brute ontological physical fact of the world that my mind experiences the color red (even if yours doesn't).
This is precisely where we need to clarify "facts of the world". We can't settle this chat until we introduce the notion of subjective vs objective, and epistemic vs ontological.
I see what you're getting at and mostly agree (hence the Upvote!). But...
Whether a 1st person qualitative experience is a "physical fact of the world" depends on your level of description. In a sense, it's not an epistemically objective physical fact that I can share with others. However, it is just a brute ontological physical fact of the world that my mind experiences the color red (even if yours doesn't).
This is precisely where we need to clarify "facts of the world". We can't settle this chat until we introduce the notion of subjective vs objective, and epistemic vs ontological.
Note that I personally believe the argument is deeply flawed, and rests on some assumptions about the human mind that may turn out to be false; and that shouldn't be generalized to other potential minds (say, AGI) even if they are true of human minds.
I was just explaining what I believe to be the core of the argument.
I was just explaining what I believe to be the core of the argument.
[deleted]
I think the fallacy is to treat knowledge of redness as a "fact" about the world.
In general, when you learn a fact, you acquire information about the world that previously you lacked. But when you first experience redness, your knowledge of the world is exactly the same as it was when you were stll Monochrome Mary. The old Mary knew which things were red, like tomatoes; she was fully-informed about the nature of light and colour. The experience of redness has added nothing to her knowledge of tomatoes and their colour.
If that's correct, then familiarity with any qualia fails to be a kind of knowledge.
In general, when you learn a fact, you acquire information about the world that previously you lacked. But when you first experience redness, your knowledge of the world is exactly the same as it was when you were stll Monochrome Mary. The old Mary knew which things were red, like tomatoes; she was fully-informed about the nature of light and colour. The experience of redness has added nothing to her knowledge of tomatoes and their colour.
If that's correct, then familiarity with any qualia fails to be a kind of knowledge.
> But when you first experience redness, your knowledge of the world is exactly the same as it was when you were still Monochrome Mary.
That is still false though, because in that moment Mary realizes what redness looks like. She has mapped a sense experience to a concept, which is new knowledge. The author has to prove that this mapping exercise is indeed not new knowledge, as making a connection between two disparate events (acquisition of concept vs acquisition of experience) is considered net new knowledge based on the epistemical definition of knowledge.
That is still false though, because in that moment Mary realizes what redness looks like. She has mapped a sense experience to a concept, which is new knowledge. The author has to prove that this mapping exercise is indeed not new knowledge, as making a connection between two disparate events (acquisition of concept vs acquisition of experience) is considered net new knowledge based on the epistemical definition of knowledge.
See my update below.
> The author has to prove that this mapping exercise is indeed not new knowledge...
Is that what you meant to write? It seems that "the author" here is referring to the paper's author (Frank Jackson), but his whole argument depends on the premise that the result of this mapping exercise is new knowledge.
It is acceptable English usage to call what Mary learns on release "knowledge", but it is not knowledge in the form of a proposition that you believe to be true; it is the memory of an experience (and whatever connections are made from that experience), and materialism does not claim or imply that you can gain the latter from reading it in a book.
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Update: With respect to the phrase I quoted, I see what you mean. This knowledge (if that is what it is) is new to Mary, but unless it existed and was knowable before Mary was released, the argument fails to show some knowledge that Mary did not know then but was knowledge at the time.
Jackson attempts to get around this by saying that she learns something about other people - specifically, that her conception of the mental life of other people was incomplete before her release and more complete after. Insofar as that conception includes objective facts, however, Mary could know those facts beforehand. Seeing colors might modify her personal justification for believing those facts (along the lines of "previously, I accepted it on the basis of what I learned verbally but now I accept it on the basis of my experience"), but note the "my experience" in that phrase: those experiences did not exist until after her release, so this justification was not available to Mary beforehand.
> The author has to prove that this mapping exercise is indeed not new knowledge...
Is that what you meant to write? It seems that "the author" here is referring to the paper's author (Frank Jackson), but his whole argument depends on the premise that the result of this mapping exercise is new knowledge.
It is acceptable English usage to call what Mary learns on release "knowledge", but it is not knowledge in the form of a proposition that you believe to be true; it is the memory of an experience (and whatever connections are made from that experience), and materialism does not claim or imply that you can gain the latter from reading it in a book.
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Update: With respect to the phrase I quoted, I see what you mean. This knowledge (if that is what it is) is new to Mary, but unless it existed and was knowable before Mary was released, the argument fails to show some knowledge that Mary did not know then but was knowledge at the time.
Jackson attempts to get around this by saying that she learns something about other people - specifically, that her conception of the mental life of other people was incomplete before her release and more complete after. Insofar as that conception includes objective facts, however, Mary could know those facts beforehand. Seeing colors might modify her personal justification for believing those facts (along the lines of "previously, I accepted it on the basis of what I learned verbally but now I accept it on the basis of my experience"), but note the "my experience" in that phrase: those experiences did not exist until after her release, so this justification was not available to Mary beforehand.
I don't think that's a substantial problem. We can reformulate the argument like this: assume that brain states correspond 1:1 to mind states. As such, for any qualia there would be a corresponding brain state. If Mary fully understands all details about light and the human mind and brain, she would be able to understand the brain state that would correspond to the qualia of her experiencing a red object. As such, she should be able to put her brain in that state.
If then she exits the room and actually looks at the color red, and if this experience is new to her, it follows that her brain is in a state that it has never been in before, which is a contradiction.
The original claim argues that this contradiction should be taken to mean that the first assumption is wrong - that brain states can't correspond 1:1 to mental states, or, equivalently, that there is no brain state that corresponds 1:1 to a qualia.
However, I believe that there is another premise which seems more obviously flawed, and which doesn't follow from this original one. That flawed assumption is that Mary could put her brain in any state she understands. I believe it's quite plausible that Mary could fully understand the brain state that corresponds to the qualia for seeing red, but still be unable to actually put her brain in that state.
In general, we don't seem to have any direct conscious control of our brain processes, just as much as we can't consciously control the function of our liver or pancreas.
If then she exits the room and actually looks at the color red, and if this experience is new to her, it follows that her brain is in a state that it has never been in before, which is a contradiction.
The original claim argues that this contradiction should be taken to mean that the first assumption is wrong - that brain states can't correspond 1:1 to mental states, or, equivalently, that there is no brain state that corresponds 1:1 to a qualia.
However, I believe that there is another premise which seems more obviously flawed, and which doesn't follow from this original one. That flawed assumption is that Mary could put her brain in any state she understands. I believe it's quite plausible that Mary could fully understand the brain state that corresponds to the qualia for seeing red, but still be unable to actually put her brain in that state.
In general, we don't seem to have any direct conscious control of our brain processes, just as much as we can't consciously control the function of our liver or pancreas.
Sorry, but I didn't take Mary's 'complete' knowledge of physics to mean that she also has insight into the workings of her own mind, still less that she can manipulate it. Justy knowing all of physics is superhuman enough.
And as it happens, I don't generally buy arguments premised on the mind being reducible to the brain.
And as it happens, I don't generally buy arguments premised on the mind being reducible to the brain.
It's part of the argument thoigh:
> She knows all the physical facts about us and our environment, in a wide sense of 'physical' which includes everything in completed physics, chemistry, and neurophysiology (emp. mine), and all there is to know about the causal and relational facts consequent upon all this, including of course functional roles.
If she knows all there is to know about neurophisiology, she obviously knows exactly how her own brain works. In the original assumption of physicalism (the one the argument ultimately wants to show is false), that also implies she knows everything about the mind.
> And as it happens, I don't generally buy arguments premised on the mind being reducible to the brain.
The whole point of this particular argument is to take that as an assumption, reach a contradiction, and conclude that the assumption is false. The Mary's Room argument is precisely an argument that the mind is separate from the brain. It's a bad argument (per some other comment, even it's creator no longer really thinks it's convincing), but I think you would agree with the conclusion.
> She knows all the physical facts about us and our environment, in a wide sense of 'physical' which includes everything in completed physics, chemistry, and neurophysiology (emp. mine), and all there is to know about the causal and relational facts consequent upon all this, including of course functional roles.
If she knows all there is to know about neurophisiology, she obviously knows exactly how her own brain works. In the original assumption of physicalism (the one the argument ultimately wants to show is false), that also implies she knows everything about the mind.
> And as it happens, I don't generally buy arguments premised on the mind being reducible to the brain.
The whole point of this particular argument is to take that as an assumption, reach a contradiction, and conclude that the assumption is false. The Mary's Room argument is precisely an argument that the mind is separate from the brain. It's a bad argument (per some other comment, even it's creator no longer really thinks it's convincing), but I think you would agree with the conclusion.
> which includes everything in completed physics, chemistry, and neurophysiology
"Completed", which I take to mean stuff that someone already understands, now. But nobody understands how changes at a neurophysiological level affect mental states and thoughts. At best, we can say that some mental states are correlated with some neurophys. phenomena.
> she obviously knows exactly how her own brain works.
Not if I have correctly understood what author meant by "completed". Nobody knows exactly how a brain works.
"Completed", which I take to mean stuff that someone already understands, now. But nobody understands how changes at a neurophysiological level affect mental states and thoughts. At best, we can say that some mental states are correlated with some neurophys. phenomena.
> she obviously knows exactly how her own brain works.
Not if I have correctly understood what author meant by "completed". Nobody knows exactly how a brain works.
I believe "completed" means precisely the opposite - current physical theories are incomplete, but Mary has access to the completed version. Otherwise, the whole argument would only prove that qualia are not part of currently understood physical theories, which not even the most convinced physicalist would contest I think.
> Additionally, while Mary may only receive information in black and white, she perceives in full colour and can see the colours of her own skin and clothes.
No, she doesn't (and never has) perceived in full color. Her entire world has been modified (Truman Show style) to shield her from ALL color at ALL times.
No, she doesn't (and never has) perceived in full color. Her entire world has been modified (Truman Show style) to shield her from ALL color at ALL times.
Related to this would be Nagel's paper, "What Is It Like to Be a Bat?" We can't say what sort of echolocation sensation a bat has anymore than Mary can say what a color looks like before she leaves the black and white room. We're in the same position when it comes to bird vision. We can't say what the world would look like with four primary colors. What does that fourth primary color look like? We don't have a word for it because we don't see that color.
Or for that matter, what would the rest of the EM spectrum look like if we could see it all? What would a scientific theory that could answer these sorts of questions look like?
Saying physicalism is false because it can't answer the questions above is not to say naturalism is false. There's no magic or supernatural stuff here. It just means our scientific description of the world lacks the subjective. There is a fundamental epistemological limit to our ability to know how to combine the two. It doesn't mean the world itself has such a division. We just can't cognate how to reconcile the two.
Or for that matter, what would the rest of the EM spectrum look like if we could see it all? What would a scientific theory that could answer these sorts of questions look like?
Saying physicalism is false because it can't answer the questions above is not to say naturalism is false. There's no magic or supernatural stuff here. It just means our scientific description of the world lacks the subjective. There is a fundamental epistemological limit to our ability to know how to combine the two. It doesn't mean the world itself has such a division. We just can't cognate how to reconcile the two.
I use echolocation all the time. Granted, I can definitely not explain how a bat feels, but... I was born with 20% vision, and kept it for roughly 6 years. After that, the world officially went dark. However, my brain was quite stubborn in not accepting that.
From that point on, my auditory system, in particular echolocation, took over. My internal field of vision did not change much. Echolocation, and my prior knowledge of the world, was used to build up my idea of my surroundings.
At first, that built-up internal image resembled very much how I saw the world prior to going blind.
However, after a few years, things started to become abstract. I lost almost all notion of clear-cut edges, and color "perception" smeared itself all over the color spectrum.
These days, what I see in my minds eye doesnt really reflect what a sighted person would visualize.
However, my minds eye still has the same function, it creates my surroundings in my head such that I can navigate and interact with the world.
That's very interesting. Bat neuroscience might be able to tell us whether bats use echolocation in a similar fashion as you described (they do also have ears and eyes, although many don't have color vision). If not, then probably they have an entirely different experience that humans when using echolocation.
It is different - not metaphysically or entirely, but... echolocation for humans is rather long-wave (although it's experienced as vision.) You can't - I couldn't - see a door edge wise so I could walk into doors pointed right at me. But bats want it for insect location, I'm betting. Much more precise, much higher frequency.
Sure, bats echolocation is more precise, basically due to the shorter wavelength, which is quite obvious if you think about it. However, what I was trying to hint at is that the function is likely equivalent, while the implementation is definitely more sophisticated when it comes to bats. The function is to build an internal representation of the external world.
> We don’t have a word for it because we don’t see that color.
I think you’re missing the argument.
We can easily assign words to things we know exist. That’s not the issue.
When we define things (like “naturalism”) we are invoking symbols and their semantics, all the stuff Mary presumably has access to in her room.
In her room, Mary already understands subjective experience, the brain mechanics behind it, etc.
The realization that there is more outside of Mary’s room suggests that our conceptualizations are limited / not accurate.
If that’s the agreed case how can anyone cling to a universal “naturalism” with a straight face?
With Mary’s room, haven’t we already accepted that formal statements are incomplete - and therefore would be silly to call universal?
I think you’re missing the argument.
We can easily assign words to things we know exist. That’s not the issue.
When we define things (like “naturalism”) we are invoking symbols and their semantics, all the stuff Mary presumably has access to in her room.
In her room, Mary already understands subjective experience, the brain mechanics behind it, etc.
The realization that there is more outside of Mary’s room suggests that our conceptualizations are limited / not accurate.
If that’s the agreed case how can anyone cling to a universal “naturalism” with a straight face?
With Mary’s room, haven’t we already accepted that formal statements are incomplete - and therefore would be silly to call universal?
Words don't excite the same bits of our brains as other physical experiences, so full knowledge of red through words and higher level thoughts is not enough for Mary. But assuming she has perfect knowledge of the the interaction of red wavelength with the eye and perfect knowledge of how the sensory input interacts with her brain, she could stick theoretically optimal electrodes in exactly the right places (or specifically tailored psychedelic drugs) and virtually experience and learn about red before actually seeing it.
> There is a fundamental epistemological limit to our ability to know how to combine the two. It doesn't mean the world itself has such a division. We just can't cognate how to reconcile the two.
I’m not convinced there’s any indication of a fundamental limit to our cognitive abilities. What if we just don’t know how subjective experience works in the same normal way that we’ve not known how other stuff works until we figured it out?
I’m not convinced there’s any indication of a fundamental limit to our cognitive abilities. What if we just don’t know how subjective experience works in the same normal way that we’ve not known how other stuff works until we figured it out?
You’ll end up in a category of your own if you “figure out” subjective experience. You’d be the greatest philosopher that ever lived.
It’s not the same problem as figuring out how the brain works physically or how subjective experiences compare in peoples brains or observable states, but whether say our experience of seeing red is the same. Or what it’s like to be a bat. You can’t break that barrier, there is not observation into another subjective. It’s like Heisenberg Uncertainty, at a certain point we reach the unobservable and by the nature of our existence can’t know what’s beyond.
It’s not the same problem as figuring out how the brain works physically or how subjective experiences compare in peoples brains or observable states, but whether say our experience of seeing red is the same. Or what it’s like to be a bat. You can’t break that barrier, there is not observation into another subjective. It’s like Heisenberg Uncertainty, at a certain point we reach the unobservable and by the nature of our existence can’t know what’s beyond.
You're just assuming that, though.
All evidence is correlational. We observe phenomena, and build causal models. The particles move this way when near this bit of metal. Given this, what's "really" there? The magnetic field, or the magnetic potential field?
I don't think there's great cause to say that this is a seperate magisterium. We just have a paucity of data compared to what future beings will have. When everyone can spin up a hundred simulated copies of their brain and trace thought-patterns in realtime, it'll seem much less mysterious.
I don't think there's great cause to say that this is a seperate magisterium. We just have a paucity of data compared to what future beings will have. When everyone can spin up a hundred simulated copies of their brain and trace thought-patterns in realtime, it'll seem much less mysterious.
I hope I didn’t make it sound like I think it would be some iterative invention like a better mouse trap, or some isolated Eureka! moment from someone who just thought hard for a bit. Perhaps that’s possible, but it feels unlikely. On the contrary, it would likely be a fundamental shift in our mode of thought and mode of explanation, less like huge discoveries like general relativity or quantum mechanics, and more like the Scientific Revolution or the Enlightenment.
I don't know either, it's just that the problem seems to be hard in a fundamental way. We would have to show how something like brain processing results in subjective experience in a way that isn't just correlation. The explanation would somehow have to show how the subjective emerges. How it's determined by the physical processes.
Then we could go make computers conscious.
Then we could go make computers conscious.
> It just means our scientific description of the world lacks the subjective.
Unless we have an independent reason to think that this thought experiment applies only to scientific knowledge, then it applies equally to all fields of propositional knowledge.
We can - and do - speak about subjective experiences by assuming that other people have them, and they are somewhat like ours (while recognizing that there are differences: some people are blind, or color-blind, or have synesthesic responses to color), but we cannot communicate what it is like to have those experiences to other people. That this is so is readily reconciled with materialism: firstly, because we cannot experience what it is like for other people to experience color, we cannot develop a common vocabulary for communicating it; secondly, even if we had the vocabulary, our conscious mind does not have the ability to bring about the necessary changes in our brain through willpower alone.
Unless we have an independent reason to think that this thought experiment applies only to scientific knowledge, then it applies equally to all fields of propositional knowledge.
We can - and do - speak about subjective experiences by assuming that other people have them, and they are somewhat like ours (while recognizing that there are differences: some people are blind, or color-blind, or have synesthesic responses to color), but we cannot communicate what it is like to have those experiences to other people. That this is so is readily reconciled with materialism: firstly, because we cannot experience what it is like for other people to experience color, we cannot develop a common vocabulary for communicating it; secondly, even if we had the vocabulary, our conscious mind does not have the ability to bring about the necessary changes in our brain through willpower alone.
On an aside, I've always loved the idea of a computer game where your character's primary sense is smell.
But how could you really convey it to a human, except visually? Although maybe something like Hellblade: Senua's Sacrifice's audio hallucinations could be a way, whispering voices that tell you the scent blows stronger this way.
But how could you really convey it to a human, except visually? Although maybe something like Hellblade: Senua's Sacrifice's audio hallucinations could be a way, whispering voices that tell you the scent blows stronger this way.
Legend of Zelda: Twilight Princess does something like this, where you play as a wolf at some point that can you track in-world smells. Kind of a blunt approach though -- the smell appears with a visual indicator that is absent when you're human.
Points for mentioning Hellblade. ;-)
I'm pretty sure detailed enough differential brain imaging of bats echolocating and not in different circumstances would eventually reveal the secrets of bat echolocation processing.
And how would that processing tell us what sort of sensation that bat has when using echolocation? Do you think doing this for birds would reveal what the fourth primary color looks like? If the answer is it wouldn't look like anything (for us), then there's something science can't tell us.
> We can't say what sort of echolocation sensation a bat has anymore than Mary can say what a color looks like before she leaves the black and white room.
Actually we can. For example, there are reports of the older generation dreaming in black and white due to the black and white tv [1], in much the same way, the days event can shape the dreams someone has. On the physical side, because science is now showing how light and other environmental stimuli affect chemical processes in the body and brain [2,3,4], science is not only discovering the ability to emit and measure, but then find instances in nature where its being used.
>what would the rest of the EM spectrum look like if we could see it all
Ultraviolent is a good example, the lens of the eye tends to block this, but people with no lens due to early cataract operations which just removed the lens, and anomalous lens have reported seeing UV light. [5,6]
>What would a scientific theory that could answer these sorts of questions look like?
So it depends on whether experts take reports seriously or not, experts applying real scientific conjecture, and/or whether funding and permission can be obtained. We can all detect Infrared (heat) through our skin, but we cant really see it. On another point, which perhaps best describes and exemplifies the boiling frog syndrome is the fact that UV destroys folates, yet we dont really detect as it takes place because its taking place over a larger perceptible window of time [7], at best those suffering from SAD or depression may feel better after a session in the tanning salon or by the end of the tanning session depending on how much UVA light the flo tubes are chucking out. It also highlights that some vegetables like Brussel Sprouts a vegetable high in folates may be harmful to your mental health during winter months, especially considering its a stable for Xmas dinners. But back to the point of what would a scientific theory look like, we already see that ad-hoc practice in action in the scientific world. Generate, Detect, Search for examples, Elucidate, Pontificate.
Scientific knowledge is not really performed in a scientific manner because it relies on the ad-hoc, if not, chaotic ability to detect phenomena, a known stumbling block, hindered in part by capitalism of all things and we all know no one person has all the ideas, and we know that some test equipment is massively expensive and in the past didnt exist. So the low hanging fruit of being able to devise tests using our own senses and imagination, think Newton's gravity theory when hit on the head by an apple, or even theory's from ancient Greeks demonstrates that in practice, scientific discovery has been extremely unscientific despite the protestations of its adherents.
>There's no magic or supernatural stuff here. It just means our scientific description of the world lacks the subjective. There is a fundamental epistemological limit to our ability to know how to combine the two. It doesn't mean the world itself has such a division. We just can't cognate how to reconcile the two.
I'm sure you are aware of the internet and search engines [8,9], if not perhaps films giving tantalizing inspiration and hope [10] of possibility's and insights into how to cognate and reconcile the current and future time beyond the realms of religions which constantly harp back to the past.
Not bad for an undergraduate of https://rb.gy/xhuwo9 if I might say so, whilst I might have spent time reading a dictionary, in order to create obedience to authority with the use of uncommon words from the vernacular of the commons, I'm not engaging in it here consciously, because the military have taught me some highly efficient means to get my message across which isn't compatible with those tenets from the law and order fraternity.
[1] https://rb.gy/xilvko
[2] https://rb.gy/grprda
[3] https://rb.gy/ahwngn
[4] https://rb.gy/j2dibr
[5] https://rb.gy/7rpejx
[6] https://rb.gy/vwgr1o
[7] https://rb.gy/yhxhlm
[8] https://rb.gy/s9wdn6
[9] https://rb.gy/5kte4d
[10]https://rb.gy/hzmop7
Actually we can. For example, there are reports of the older generation dreaming in black and white due to the black and white tv [1], in much the same way, the days event can shape the dreams someone has. On the physical side, because science is now showing how light and other environmental stimuli affect chemical processes in the body and brain [2,3,4], science is not only discovering the ability to emit and measure, but then find instances in nature where its being used.
>what would the rest of the EM spectrum look like if we could see it all
Ultraviolent is a good example, the lens of the eye tends to block this, but people with no lens due to early cataract operations which just removed the lens, and anomalous lens have reported seeing UV light. [5,6]
>What would a scientific theory that could answer these sorts of questions look like?
So it depends on whether experts take reports seriously or not, experts applying real scientific conjecture, and/or whether funding and permission can be obtained. We can all detect Infrared (heat) through our skin, but we cant really see it. On another point, which perhaps best describes and exemplifies the boiling frog syndrome is the fact that UV destroys folates, yet we dont really detect as it takes place because its taking place over a larger perceptible window of time [7], at best those suffering from SAD or depression may feel better after a session in the tanning salon or by the end of the tanning session depending on how much UVA light the flo tubes are chucking out. It also highlights that some vegetables like Brussel Sprouts a vegetable high in folates may be harmful to your mental health during winter months, especially considering its a stable for Xmas dinners. But back to the point of what would a scientific theory look like, we already see that ad-hoc practice in action in the scientific world. Generate, Detect, Search for examples, Elucidate, Pontificate.
Scientific knowledge is not really performed in a scientific manner because it relies on the ad-hoc, if not, chaotic ability to detect phenomena, a known stumbling block, hindered in part by capitalism of all things and we all know no one person has all the ideas, and we know that some test equipment is massively expensive and in the past didnt exist. So the low hanging fruit of being able to devise tests using our own senses and imagination, think Newton's gravity theory when hit on the head by an apple, or even theory's from ancient Greeks demonstrates that in practice, scientific discovery has been extremely unscientific despite the protestations of its adherents.
>There's no magic or supernatural stuff here. It just means our scientific description of the world lacks the subjective. There is a fundamental epistemological limit to our ability to know how to combine the two. It doesn't mean the world itself has such a division. We just can't cognate how to reconcile the two.
I'm sure you are aware of the internet and search engines [8,9], if not perhaps films giving tantalizing inspiration and hope [10] of possibility's and insights into how to cognate and reconcile the current and future time beyond the realms of religions which constantly harp back to the past.
Not bad for an undergraduate of https://rb.gy/xhuwo9 if I might say so, whilst I might have spent time reading a dictionary, in order to create obedience to authority with the use of uncommon words from the vernacular of the commons, I'm not engaging in it here consciously, because the military have taught me some highly efficient means to get my message across which isn't compatible with those tenets from the law and order fraternity.
[1] https://rb.gy/xilvko
[2] https://rb.gy/grprda
[3] https://rb.gy/ahwngn
[4] https://rb.gy/j2dibr
[5] https://rb.gy/7rpejx
[6] https://rb.gy/vwgr1o
[7] https://rb.gy/yhxhlm
[8] https://rb.gy/s9wdn6
[9] https://rb.gy/5kte4d
[10]https://rb.gy/hzmop7
Our eyes are sensors! We collect data from them, if Mary doesn't know what Red looks like, hence she lacks this data. Hence, she doesn't know all the physical facts about the universe.
The initial point, of Mary, knowing all Physical facts hence doesn't seem to make sense, and therefore looks flawed!
The initial point, of Mary, knowing all Physical facts hence doesn't seem to make sense, and therefore looks flawed!
But Mary does have all this data in her room - she knows every last interaction of wavelength to eyeball to neurons from her studies.
What doesn't Mary know in her room? You're proposing that you can codify that in some special (data-fied, 'factual') way that she couldn't possibly have access to in her room.
What is that codification, then? Be specific.
If you (we) can't do that, then aren't we just lunatics screaming and uttering and pointing at conscious experience with no ground?
What doesn't Mary know in her room? You're proposing that you can codify that in some special (data-fied, 'factual') way that she couldn't possibly have access to in her room.
What is that codification, then? Be specific.
If you (we) can't do that, then aren't we just lunatics screaming and uttering and pointing at conscious experience with no ground?
What we know by experience, by abstraction, or empirically, are three distinct modes of knowing. Experiences are directly known and always true. (Experiences might reference other potentially false things, and might be false indirectly.)
That resolves the whole Mary knowledge problem. Books cannot inject that kind of direct knowledge. Thus the claim "mary knows everything" is either false, or only true for a smaller domain.
One can think of analogies, like tamper resistant logs, or unique CPU states while doing static analysis vs running a program.
All in all, the non-physicalist conclusions are widely overdrawn. More over, for what it is worth, Jackson himself no longer thinks this argument is a good one.
That resolves the whole Mary knowledge problem. Books cannot inject that kind of direct knowledge. Thus the claim "mary knows everything" is either false, or only true for a smaller domain.
One can think of analogies, like tamper resistant logs, or unique CPU states while doing static analysis vs running a program.
All in all, the non-physicalist conclusions are widely overdrawn. More over, for what it is worth, Jackson himself no longer thinks this argument is a good one.
Degree in philosophy, and ... used to read this sort of stuff for fun 30 years ago. Now... it's just like Mary seeing red; "ho-hum". I remember reading some Churchland years ago - I may have even read some of this back and forth exchange in some class years ago. I sense that this is more an issue of language than ideas, and people talking past each other. When it happens in the moment - face to face, perhaps - it's... at least interesting. You can at least try to determine if people are misusing language/ideas, and rectify it in the moment. You can't do that with papers like this. It feels like reading a Gish gallop.
I don't really understand the setup.
It seems to suggest that physicalism claims all things can be learned intellectually, in a box. It seems obvious to me that sensory experiences could be physical in nature yet also can only be learned experientially.
Is there really a debate that learning about color and seeing color are not the same things?
I don't know if the setup is unfair or the physicalism being referred to is silly. Either way this seems pointless to me.
It seems to suggest that physicalism claims all things can be learned intellectually, in a box. It seems obvious to me that sensory experiences could be physical in nature yet also can only be learned experientially.
Is there really a debate that learning about color and seeing color are not the same things?
I don't know if the setup is unfair or the physicalism being referred to is silly. Either way this seems pointless to me.
I still don't know what it is supposed to mean to know what it's like to see red. Having seen red, I have a memory of having been in a state of seeing red. Not having seen red I wouldn't have such a memory. But this has no consequence for physicalism. I can imagine myself in the situation of having seen red, e.g. imagining myself viewing a red apple. But I have aphantasia and so I'm certainly not remembering or imagining red in any meaningful sense. In no way is my memory of being in a state of seeing red presently constituted by phenomenal red. When we imagine red or some visual experience, we know the early visual areas of the brain involved in those sensory experiences are reactivated by feedback signals from the frontal cortex. Presumably seeing red gives me this ability which one lacks before seeing red. But this has no consequences for physicalism either. Besides, the article claims the issue isn't about being able to imagine red. So what is the nature of this supposed knowledge? The whole concept seems dubious.
It might help to imagine a different world.
One in which Mary steps out of her room, sees a rose, and absolutely nothing new is added to her understandings.
She already had it all sorted out in her study. In many people’s understanding of “naturalism” that wouldn’t be any surprise.
But that’s not this world.
One in which Mary steps out of her room, sees a rose, and absolutely nothing new is added to her understandings.
She already had it all sorted out in her study. In many people’s understanding of “naturalism” that wouldn’t be any surprise.
But that’s not this world.
If she truly possesses all physical knowledge, then she knows exactly what every possible rose looks like from every possible angle, in every possible setting and lighting. She knows in excruciating detail, at the level of every individual atom, how the scent of the rose will reach her brain, and exactly what responses it will trigger.
And indeed had she that knowledge, nothing new would be added by seeing one in person.
The implausible part is presupposing any person could ever have a complete enough understanding of all physical knowledge to achieve that.
And indeed had she that knowledge, nothing new would be added by seeing one in person.
The implausible part is presupposing any person could ever have a complete enough understanding of all physical knowledge to achieve that.
There is computation done in Mary's system for which Mary doesn't have insight into, so what she doesn't know is the results of that computation she is bound to experience nonetheless.
Here is a short summary of the idea: https://leibgruber.blogspot.com/2022/08/the-missing-knowledg...
Here is a short summary of the idea: https://leibgruber.blogspot.com/2022/08/the-missing-knowledg...
Well this text at least accomplishes a purpose... The purpose of showing us that not every philosopher is particularly smart
Does the experience of zero-gravity reveal information not otherwise available via its deduction from physical law?
Interesting example. There have been many [failed] efforts to try to recreate the overview effect [1] on Earth. One hypothesis for the reason that facsimiles (e.g. VR) of such don't drive the same experience as the real thing, is that zero-gravity is somehow a component of it.
[1] - https://en.wikipedia.org/wiki/Overview_effect
[1] - https://en.wikipedia.org/wiki/Overview_effect
This whole waste of breath is based on the obviously artificial distinctions between knowledge, experience, sensing, imagination and whatever other made up modes of thought this person comes up with.
"Mary knows every fact"
"Experiences are not facts"
"Therefore physicalism is false" I mean come on how did this get published ???
"Mary knows every fact"
"Experiences are not facts"
"Therefore physicalism is false" I mean come on how did this get published ???
There are facts about experiences. What is the experience of a fourth primary color? We're in a similar position to Mary before she leaves the room.
There are facts about experiences (such as the fact that some people have perfect pitch), and Mary can learn those facts from a book. It is a premise of this thought experiment, however, that you cannot learn things such as what it is like to see colors (or to have perfect pitch ourselves, for that matter) from books. The notion that this presents some sort of challenge to materialism comes from a) the way we use "to know" polysemously (at least in English), to refer both to having both factual information and memories of sensory input and emotions, and b) the misdirection of limiting what Mary studies to physics, as if this limitation on what you can learn from book studies was particular to the physical sciences. The argument is ultimately trivial, as its conclusion does not go beyond its tacit premise.
There's also the experience of knowing something, and I imagine it's like parentheses, exactly the same as knowing something. Again this whole know/experience distinction is presumptuous given our knowledge of neurobiology.
Case in point, I can guess that the experience of a fourth primary color is going to be close to one of another color. I know it's not going to be warm or anything (I'll guess that it looks kind of shimmery purple, why not, purple's mysterious). People do the same with drugs - it binds to XYZ receptor, releases ABC hormone; and just from some pharmokinetic principles you can guess fairly well how it's going to feel.
Case in point, I can guess that the experience of a fourth primary color is going to be close to one of another color. I know it's not going to be warm or anything (I'll guess that it looks kind of shimmery purple, why not, purple's mysterious). People do the same with drugs - it binds to XYZ receptor, releases ABC hormone; and just from some pharmokinetic principles you can guess fairly well how it's going to feel.
In other words, "You can't derive 1st-person qualia from 3rd-person physics alone."
I've studied this for decades and it's a recurring theme not only with Jackson's "Mary" thought experiment, but with Nagel's "Bat", Searle's "Chinese Room", Leibniz's "Mill", etc.
The reason these arguments are often difficult to appreciate is because we struggle to put ourselves in the minds of other people, wondering how/if they perceive the world, but all the while we are using terms whose meanings and experiences we already understand intimately (e.g. red, rose, tomato... in the case of the Mary argument.)
The argument would have a bit more force if you imagined yourself landing on a strange new planet inhabited by Zorlichs. Zorlichs often drink Byzerp, which is a beverage made from Slayrne, Mucche, and Karlne. You're an expert molecular chemist. You've studied these ingredients for months and you now know all there is to know about Slayrne, Mucche, and Karlne. You know how they interact not only with each other but also with human biology (e.g. you'll know at least whether this beverage would harm you or not). Oh, you also happen to be a very picky person. Your entire life, you've never consumed any food or beverage that wasn't entirely bland. That means, you yourself have never had anything sweet, salty, bitter, or fizzy. So the question is: Would you know/learn something new to YOU upon first tasting Byzerp?
If we take "learn" to mean "acquire new experiences", then Mary certainly learns something new upon seeing red for the first time. Keep in mind that people can (and often do) learn something that is fleeting in time: you might have "taught" me how to bake brownies last year and, in that moment, I truly understood... that is too say, I was following along and comprehended every step along the way. But now it's 2023 and I've done nothing with that experience since. Indeed, I kinda forgot most of it. Is it now fair to say of me that I "know" how to make brownies?
"I learned" doesn't necessarily mean "I know".
And that flows both ways. Mary "knows" all there is to know about colour vision because she studied 3rd person objective facts about the world: light waves, retinas, brains, etc. But, if we stick with my definition of "learn" (i.e. "acquire new experiences") then Mary obviously hasn't learned what it is like to have a 1st-person red rose experience until she has that very experience.
That's not to say all learning must be a direct 1st person experience of the matter. I can learn all about the objective facts of skydiving without having experienced it firsthand. But I'll never know the subjective qualia of falling out of a plane towards the earth below until I actually do it.
Mary would have thought: "I don't know what it's like to see red." in the same way I currently think "I don't know what it's like to skydive". Yet both or worlds would be rocked (that is too say "learn something new") upon actually having the experience.
I've studied this for decades and it's a recurring theme not only with Jackson's "Mary" thought experiment, but with Nagel's "Bat", Searle's "Chinese Room", Leibniz's "Mill", etc.
The reason these arguments are often difficult to appreciate is because we struggle to put ourselves in the minds of other people, wondering how/if they perceive the world, but all the while we are using terms whose meanings and experiences we already understand intimately (e.g. red, rose, tomato... in the case of the Mary argument.)
The argument would have a bit more force if you imagined yourself landing on a strange new planet inhabited by Zorlichs. Zorlichs often drink Byzerp, which is a beverage made from Slayrne, Mucche, and Karlne. You're an expert molecular chemist. You've studied these ingredients for months and you now know all there is to know about Slayrne, Mucche, and Karlne. You know how they interact not only with each other but also with human biology (e.g. you'll know at least whether this beverage would harm you or not). Oh, you also happen to be a very picky person. Your entire life, you've never consumed any food or beverage that wasn't entirely bland. That means, you yourself have never had anything sweet, salty, bitter, or fizzy. So the question is: Would you know/learn something new to YOU upon first tasting Byzerp?
If we take "learn" to mean "acquire new experiences", then Mary certainly learns something new upon seeing red for the first time. Keep in mind that people can (and often do) learn something that is fleeting in time: you might have "taught" me how to bake brownies last year and, in that moment, I truly understood... that is too say, I was following along and comprehended every step along the way. But now it's 2023 and I've done nothing with that experience since. Indeed, I kinda forgot most of it. Is it now fair to say of me that I "know" how to make brownies?
"I learned" doesn't necessarily mean "I know".
And that flows both ways. Mary "knows" all there is to know about colour vision because she studied 3rd person objective facts about the world: light waves, retinas, brains, etc. But, if we stick with my definition of "learn" (i.e. "acquire new experiences") then Mary obviously hasn't learned what it is like to have a 1st-person red rose experience until she has that very experience.
That's not to say all learning must be a direct 1st person experience of the matter. I can learn all about the objective facts of skydiving without having experienced it firsthand. But I'll never know the subjective qualia of falling out of a plane towards the earth below until I actually do it.
Mary would have thought: "I don't know what it's like to see red." in the same way I currently think "I don't know what it's like to skydive". Yet both or worlds would be rocked (that is too say "learn something new") upon actually having the experience.
Like most arguments of this type it assumes the conclusion then acts like it’s terms don’t do that.
If Mary knows everything about red then she also knows what seeing it is like. If she doesn’t… then she doesn’t. They try to have it both ways by hand waving & hiding behind colloquial language but it still comes down to that in the end.
The thought experiment just reveals the writers own biases & limitations of thought rather than be revelatory in any way.
In fact this paper is often used by opponents of qualia as demonstrating why they are nonsensical & incoherent.
Got to say, I agree. Daniel Dennett has his flaws but his argument that this type of thought experiment is a category error & that qualia do not exist and are incompatible with what are basic facts we know about neuroscience should have ended this years ago.
If Mary knows everything about red then she also knows what seeing it is like. If she doesn’t… then she doesn’t. They try to have it both ways by hand waving & hiding behind colloquial language but it still comes down to that in the end.
The thought experiment just reveals the writers own biases & limitations of thought rather than be revelatory in any way.
In fact this paper is often used by opponents of qualia as demonstrating why they are nonsensical & incoherent.
Got to say, I agree. Daniel Dennett has his flaws but his argument that this type of thought experiment is a category error & that qualia do not exist and are incompatible with what are basic facts we know about neuroscience should have ended this years ago.
> If Mary knows everything about red then she also knows what seeing it is like.
Not necessarily. And if you assert it is true, then it can be true only in a limited sense.
Can you "know everything" about playing guitar if you've never actually done it yourself? I think you'll agree with me when I say the answer varies:
It's "Yes", if you mean "know everything" to stand for something like "know everything objective that can be passed along to another person without any loss whatever." (I'm thinking of things like how guitars are made, how they're tuned, how you play them, etc.)
But it's "No" if you mean "know everything" to also include your subjective first person experience of actually playing a real guitar (and why wouldn't you include that as part of your "know everything"?) If the subjective feeling is something to be known, then it ought to be included as part of your "know everything" list, right? (If not, why not?)
Not necessarily. And if you assert it is true, then it can be true only in a limited sense.
Can you "know everything" about playing guitar if you've never actually done it yourself? I think you'll agree with me when I say the answer varies:
It's "Yes", if you mean "know everything" to stand for something like "know everything objective that can be passed along to another person without any loss whatever." (I'm thinking of things like how guitars are made, how they're tuned, how you play them, etc.)
But it's "No" if you mean "know everything" to also include your subjective first person experience of actually playing a real guitar (and why wouldn't you include that as part of your "know everything"?) If the subjective feeling is something to be known, then it ought to be included as part of your "know everything" list, right? (If not, why not?)
An analogy with a computer makes this quite obvious. If we imagine an AI running on a CPU similar to those we know, and given free reign to interact with everything including the contents of the computer as well, it's easy to see that an AI-Mary would not need to leave the room to experience the color red - it could simply alter its input channels/memory to generate the exact experience that its sensors would detect if they were pointed at a red object.
If however we alter the AI such that it can't access/modify its sensors directly, and it's sensors write data to a piece of memory that the AI also can't write to, then the AI-Mary will not be able to put itself in exactly the same state it would be in were its sensors pointed at a red object, and so would have some kind of a new experience when leaving the room.
But, this would not be some fundamental fact about subjective experience or qualia, it would simply be a limitation of the architecture.