Mary's Room
Mary's Room/Knowledge Argument as proposed by philosopher Frank Cameron Jackson is as follows:
1. Mary knew everything physical about the color red but has never seen the color red
2. IF Mary learns something new when she actually sees red THEN Mary didn't know all that there is to know about the color red before she actually saw the color red
3. Mary learns something new when she actually sees red
4. Mary didn't know all that there is to know about the color red before she actually saw red (2, 3 Modus ponens)
5. IF Mary knew everything physical about the color red AND Mary didn't know all that there is to know about the color red before she actually saw red THEN physicalism is false
6. Mary knew everything physical about the color red AND Mary didn't know all that there is to know about the color red (1 and 4 conjunction)
7. Physicalism is false (5, 6 modus ponens)
Jackson's use of the word "knew" needs to be clarified. When Jackson claims Mary "knew everything physical about the color red" he refers to everything except the direct experience of redness and that implies Jackson is of the view that physicalism entails that knowing what brain-state corresponds to actually seeing red should evoke the brain-state of actually seeing red but that's an odd and false claim to make because the brain-state of knowing what brain-state corresponds to actually seeing red and the brain-state of actually seeing red are themselves two different brain-states and being different they can't have the same effect. To clarify further, suppose x is the brain-state of seeing the color red and y the brain-state of knowing x. Clearly x and y are different but, most importantly, both [s]are[/s] can be brain-states i.e. Mary's room argument fails to achieve its intended objective of refuting physicalism.
@InPitzotl@Wayfarer@fishfry@Pfhorrest OP updated based on comments by you all
Another issue or the main issue with Jackson's argument is that he makes two statements:
1. Mary has complete physical knowledge of red
and
2. Mary has never actually seen red
Statements 1 and 2 form part of the following subargument
1. Mary has complete physical knowledge of red
1a. Complete physical knowledge can't account for actually seeing red
Therefore
2. Mary has never actually seen red
Statement 1a is an assumption Jackson makes but, as we already know, it is also the conclusion of Mary's Room argument. Begging the question fallacy.
1. Mary knew everything physical about the color red but has never seen the color red
2. IF Mary learns something new when she actually sees red THEN Mary didn't know all that there is to know about the color red before she actually saw the color red
3. Mary learns something new when she actually sees red
4. Mary didn't know all that there is to know about the color red before she actually saw red (2, 3 Modus ponens)
5. IF Mary knew everything physical about the color red AND Mary didn't know all that there is to know about the color red before she actually saw red THEN physicalism is false
6. Mary knew everything physical about the color red AND Mary didn't know all that there is to know about the color red (1 and 4 conjunction)
7. Physicalism is false (5, 6 modus ponens)
Jackson's use of the word "knew" needs to be clarified. When Jackson claims Mary "knew everything physical about the color red" he refers to everything except the direct experience of redness and that implies Jackson is of the view that physicalism entails that knowing what brain-state corresponds to actually seeing red should evoke the brain-state of actually seeing red but that's an odd and false claim to make because the brain-state of knowing what brain-state corresponds to actually seeing red and the brain-state of actually seeing red are themselves two different brain-states and being different they can't have the same effect. To clarify further, suppose x is the brain-state of seeing the color red and y the brain-state of knowing x. Clearly x and y are different but, most importantly, both [s]are[/s] can be brain-states i.e. Mary's room argument fails to achieve its intended objective of refuting physicalism.
@InPitzotl@Wayfarer@fishfry@Pfhorrest OP updated based on comments by you all
Another issue or the main issue with Jackson's argument is that he makes two statements:
1. Mary has complete physical knowledge of red
and
2. Mary has never actually seen red
Statements 1 and 2 form part of the following subargument
1. Mary has complete physical knowledge of red
1a. Complete physical knowledge can't account for actually seeing red
Therefore
2. Mary has never actually seen red
Statement 1a is an assumption Jackson makes but, as we already know, it is also the conclusion of Mary's Room argument. Begging the question fallacy.
Comments (126)
Mary knows everything about what brains seeing the color red are like, in the third person: she can look at a brain and tell you if it's seeing red, and do stuff to a brain to make it see red.
But Mary doesn't know what it's like to be a brain seeing red, in the first person, until she has been a brain seeing red. She could use her knowledge about brains and their relation to the perception of redness to induce that state in herself and then know it, but until she actually does that, she doesn't know it.
And that doesn't require that anything non-physical exists. Just that there's a differences in experience between observing a physical object in the third person, and being that same kind of physical object in the first person.
But, you're talking about a person. Are persons objects? Is 'an object in the first person' even an intelligible statement? Objects are known, by definition - an object exists in the relation to the knowing subject. So 'being a physical object in the first person' is a nonsensical statement. Humans are beings - that's their designation!
Yes. Every thing is an object, persons included.
At least some objects are also subjects, and it is the being-of-that-kind-of-thing-in-the-first-person that makes up their subjectivity.
Furthermore, I hope you're sufficiently sensitive to understand that the idea of viewing humans as objects is de-humanising.
Just as an additional point of clarification... once Mary sees red for the first time (fast forward through all of the "learning how to see" red to this point), Mary is experiencing red, and that is a brain state.
Now, let's have Mary do nothing but walk back into the room... no red objects allowed. There is likely, presumably, another new brain state... that of Mary knowing that she saw red.
I'm not objecting to anything here... but oft in these discussions the treatment of experience is equated to treatment of remembering having an experience, and I wish to point out that these two things are also separate. The former is where the "what-it's-likes" apply... but the latter is really a form of a self-model (knowledge-that one has experienced x is a model that there's such a thing as an experience of x, that you had it, that you are capable of having it under certain kinds of situations, and possibly that you are capable of recognizing the experience and comparing it to the particular past one).
I'm not sure this actually describes a physical system well, or that saying that this is "the ambition of science" says anything meaningful. Maxwell's Demon vs the 2LT, for example, seems to suggest that even in the most deterministic of worlds predictability may not be allowed.
...and I'm not sure you can say that either.
From the SEP entry on the topic:
Why do you think is the philosophical significance of the argument against physicalism? What is at issue, in your view?
Nobody has ever seen a brain state, furthermore, whether it is possible to establish correspondences between so-called brain states and first-person experience is exactly the point at issue. You will notice in many of the analyses of this 'thought-experiment' that it is simply taken for granted that states of being can be understood as brain states, but that in itself is simply an assumption. Many of these kinds of arguments date back a few decades, when there was the confident belief that eventually science would develop to the point where you could directly 'see' a brain state. But when fMRI became a reality, there are still many major conceptual difficulties in doing precisely that (see this.) The brain, as is well known, has more neural connections than there are stars in the sky, so 1960's materialism looks increasingly quaint in my view.
Anyway I have to sign out of this discussion, I will just annoy everyone here and it will be mutual. Bye.
I think you've misread something. You quoted me as objecting to the meaningfulness of saying that science's ambition is "of course" to extend the level of prediction and control over all of nature. Following that anthropomorphic attribution of motive to science, you start quoting SEP's entry on the knowledge argument.
Quoting Wayfarer
I think generalizing the motive behind objecting to physicalism has the same flaw as generalizing the motive of science; people have motives, ideas do not. I could speculate about what people's motives generally are, but I'm not sure I'm well informed enough in statistics of what's going on in peoples' minds to realistically apply any truth criteria to the matter.
As for what KA is about, we experience things, and there's some disagreement over whether or not to call that experiencing a physical process. I'm not sure at the lowest level if anything even is at stake; if it boils down to two different views of what "physical" means, then the stakes may very well be illusory.
I was only able to follow the first couple of sentences then got lost.
My understanding of this fascinating example is that after her color vision is restored (or she goes outside for the first time, or whatever) she learns something new: namely, what it's like to see the color red.
The point being that qualia are a form of knowledge. Knowledge is not only about what's "out there," but also what it's like to experience the stuff out there. Therefore, qualia are meaningful and count as information about the world. Therefore, any theory of mind (computationalism, physicalism, etc.) must account for subjective experience.
In other words if someone claims that the world is a computer simulation or that the mind is a computer program that could be uploaded to digital hardware operating according to the laws of physics; my response is to challenge them to explain qualia and self-awareness. How does a Turing machine come to know what it feels like to compute? If they can't answer that, I can dismiss their argument.
There is still the open question of what it is that makes at least some objects subjects, sure. But all that Mary’s Room proves is that there is more than just being an object to consider: there is also being a subject. It only disproves eliminativism, not physicalism. If some kind of emergentism or panpsychism can pan out, then physicalism is still tenable. I think emergentism has basically the same problems as substance dualism, which leaves only panpsychism.
Viewing them as ONLY objects is dehumanizing because it denies their subjectivity, their agency. But all subjects are also objects, and that’s not dehumanize.
Then the problem isnt a lack of knowledge about red, but about brains seeing red. And knowing everything physical includes knowing what it looks like. It's an assumption that seeing red isn't a physical causal process.
Quoting TheMadFool
This is actually the essence of Paul Churchland's response "Knowing Qualia: A Reply to Jackson", in which he shows that Jackson uses the term "knows about" in two different senses. The knowledge of physics that Mary has learned from her studies is entirely propositional (i.e. expressed in textbooks or lectures as a series of sentences that are distilled into propositions), while knowing "what it is like" is not propositional (if we could express it that way, then presumably Mary could have learned it before her release; Jackson is implicitly making hIs case on the reasonable assumption[1] that one cannot do this.)
In response, there have been suggestions that qualia are somehow propositional, as in phrases like "Seeing red has the phenomenal character R", but the people making such claims are never able to say what R is, so to say that I am skeptical of this claim is quite an understatement.
The inability to put qualia into words presents no challenge to physicalism. Language depends on a shared vocabulary, and a shared vocabulary ultimately depends on shared experience, but none of us can experience other peoples' sensory experiences directly, as we can our own, for a straightforward physical reason: our brains are not physically connected to theirs. The only reason we can talk of them at all is under the assumption that they are somewhat similar for other people, and there are many well-known cases where this is not exactly so (color blindness being just one example.)
Another way of putting the equivocation is in the ambiguity of the phrase "physical knowledge." In Jackson's usage, he is referring to knowledge of physics, but physicalism does not imply or depend on all knowledge being about physics; what it does imply is that knowledge cannot be gained without there being physical change within the entity doing the learning.
[1] Dennett disagrees that this is a reasonable assumption, on the grounds that this just assumes that knowing all the physics is much the same as knowing just a lot of it. Hence he calls Jackson's argument an intuition pump, and saying, as Jackson did, that it is "just obvious" that Mary will learn something on her release, is about as good an argument as saying that it is just obvious that the sun moves and the earth is stationary.
I don't think it's even possible to define red in terms of an experience. How are you going to tell me which experience the color red is?
It's strange that pre-school kids understsnd what is being said, but adults and philosophers with degrees don't?
But that's conveying an "equivalence class" of objects and associating it with an "equivalence class" of sounds. This exercise requires me to recognize what "same sound" means, but let's grant that as a detail (and also, btw, we need to recognize objects as "not red"). I am then expected to have a capability of seeing that some of these objects have a "same-ness" to them and some a "different-ness"... if say I'm a protanope, I would have some difficulties here. If hypothetically I were a tetrachromat, it might be a bit confusing at first but I'd be able to pull it off.
But none of these are requiring me to match my experience to the teacher's experience. Quite the contrary; I'm being asked to recognize common and distinct properties "of" objects... the exercise is treating color as-if it's a property of objects. The entire exercise is ignoring experience... except insofar as it is used for me to measure this property "of" objects. E.g., if I had an "inverted spectrum", nobody would be the wiser, or even care.
Your inverted spectrum would still be consistent, where your blue equals my red, and you always experience blue when I experience red, then that says something consistent about the objects in question, that they reflect the same wavelength of light. We both would share this idea that the wavelenghts are the same for each of us even if the color we experience may be different, but that isn't saying anything about the object rather it is saying something about us as different individuals with different eyes and brains that interpret the wavelength that enters our eyes. It's no different than learning a different language's word for red. We would both be using a different word referring to the same thing just as we would use different colors to refer to the same thing.
Agreed.
Quoting Harry Hindu
Well, it's this:
Quoting Harry Hindu
Quoting Harry Hindu
A and B conflict. If we define h-red to be the experience you have when you look at a red crayon, then this category would be completely useless... only Harry Hindu could relate to it. If instead, we define c-red to be the "same color" as the crayon with "red" written on it (as we do in the kindergarten), then we could talk about said things, so long as we demonstrate the capability of recognizing what "same color" means, which we can establish with your kindergarten exercises for about 95% of individuals.
Quoting Harry Hindu
That's closer to being right, but note that this isn't an "experience" versus "wavelength" argument at this point, given we've introduced new entities with properties to consider (like "eyes").
Jackson claims to have proven that physicalism is false, so physicalists can logically assume that physicalism is correct in any counter-argument - it is Jackson who has taken on the burden of proof in showing that this must be wrong. Dennett made this point in What RoboMary Knows:
"Before turning to the interesting bits, I must consider what many will view as a pressing objection:
"'Robots don’t have color experiences! Robots don’t have qualia. This scenario isn’t remotely on the same topic as the story of Mary the color scientist.'
"I suspect that many will want to endorse this objection, but they really must restrain themselves, on pain of begging the question most blatantly. Contemporary materialism–at least in my version of it–cheerfully endorses the assertion that we are robots of a sort–made of robots made of robots. Thinking in terms of robots is a useful exercise, since it removes the excuse that we don’t yet know enough about brains to say just what is going on that might be relevant, permitting a sort of woolly romanticism about the mysterious powers of brains to cloud our judgment. If materialism is true, it should be possible (“in principle!”) to build a material thing–call it a robot brain–that does what a brain does, and hence instantiates the same theory of experience that we do. Those who rule out my scenario as irrelevant from the outset are not arguing for the falsity of materialism; they are assuming it, and just illustrating that assumption in their version of the Mary story. That might be interesting as social anthropology, but is unlikely to shed any light on the science of consciousness."
Quoting Wayfarer
Even with neural networks, it is pretty difficult to see how they perform their party tricks, despite us having complete access to their mechanisms, yet I do not think anyone is suggesting that they are non- or extra-physical. Anyone who hoped that fMRI, which gives a very much more coarse-grained view of what is happening than we have of neural nets, would solve the mind-body problem, was being unrealistically optimistic.
Quoting InPitzotl
I think I can give an analogy which shows why this approach is not useful.
Suppose we have two different computers; say an ARM device running Linux and an Intel PC running Windows. Each has the same database on it (say, Postgres, though, because of the different architectures of the hardware, these will be different implementations of the same design.) In each case, the databases encrypt the data they store, though with different keys. Finally, suppose we store the same information in each of the databases, but we input it in a different order on each.
After this exercise, there will be almost nothing in common about the physical state of the two machines, and, as they do their work, there will be almost no commonality in the sequence of instructions they perform, yet, if there are no bugs, they will be perceived to function identically by their ordinary users. This commonality extends to various 'introspective' tools available to ordinary users, such as those that report the schema and the number of rows in each table. Absent any other clues, an ordinary user could not tell them apart.
System administrators, however, have additional tools at their disposal, which allow them to see how their machine works at a low level - they can see how the data is physically stored on the disks, and they can examine the programs and see how they do the work. The adminstrator of one machine will see it differently than does the administrator of the other see hers, but unless a person has administrator access to both machines, she will not be able to see for herself how the two differ.
In this analogy, our access to our own brains is like that of ordinary users, and we have no access to other peoples' brains other than what their ordinary users report to us. And no-one has yet achieved anything like administrative access to their own brains, let alone anyone else's.
It is probably not necessary for me to say what the point is here, but just for completeness, what matters is an abstract, emergent view of the physical state and function, and so long as, in each case, there is some mapping, not necessarily the same mapping, from this to the low-level state and function, physicalism is not disproved.
Quoting InPitzotl
Then we aren't talking about knowing red, rather we are talking about knowing what it is like for Harry to see red - Harry's red vs. A Raybould's red. What use would knowing how each of us experiences colors separate from knowing how light interacts with our eye-brain system individually?
I should say that I don't believe that we each experience different colors when looking at the same thing. We are related - members of the same species that evolved from prior species with eyes and brains, therefore we should experience things similarly.
Correct.
Quoting Harry Hindu
That argument isn't compelling. Being of the same species suggests tons of similarities, and we do have those... we generally tend to have opposable thumbs, walk upright, sweat, etc. But there are also a lot of differences that we have; different eye colors, body types, hair types, etc. Simply being of the same species is not enough to suggest we have the same color experiences; I would be more compelled if the argument specifically invoked studies of how the process of learning color works, and supported the thesis that there's a common representation (under the presumption that the nature of experience is built by the nature of the representation, and various other caveats)... but to simply conclude that the color experiences are the same because we're all human sounds to me more like guesswork.
Sure, thanks to differences in genes. What differences in genes would we point to that makes us experience different colors when looking at the same thing?
Or differences in development.
You have this backwards. Both alleles and environmental differences exist in the human genome and human development; both in general, and in relation to known traits involving the visual system (e.g., there are alleles of genes that express the precise chemistry of your cone opsins; and vast differences in the distribution of cones between eyeballs); so it's dubious to just a priori speculate that there's no variance in the visual system elsewhere (in this particular case, in factors related to how color winds up getting experienced).
You have a same-experiences conjecture based on us all being the same species. That translates to a hypothesis that the development of color experiences in humans is largely independent of alleles and environmental variations in brain development.
And that is the thing you need to demonstrate in order to able to say that you have an adequately justified conjecture.
Ah. Nice distinction. Well I'm no philosopher so I can't go down this rabbit hole. But just because subjective knowledge isn't propositional doesn't mean it's not real, not part of the universe that needs to be explained. After all the logos isn't everything; there's also the mythos, right?
If physics is propositional and everything that's not propositional doesn't count as actual knowledge (or whatever argument is being made by the anti-Jacksons) then this IMO is scientism versus science.
If you reject everything in the world that's not propositional, you limit yourself to words and symbols and you ignore the rest of reality, the nonverbal part. The experiences you had as a baby before you acquired words. The experiences you have as an adult that go beyond words. Faith and qualia being two examples that come to mind.
I should add, if I haven't made it clear, that I'm in no position to hold up my end of an argument here. I know the Mary's room story but not any of the lengthy arguments and counter-arguments that arose from it. You've already educated me. Still, I'm not one who believes that all knowledge is propositional. That viewpoints dismisses the most important aspects of life.
Perfect. Then we can know about color experiences given that we know how alleles of genes that express the precise chemistry of your cone opsins; and vast differences in the distribution of cones between eyeballs.
There are some who disagree, but personally I agree that subjective knowledge is real. What makes it subjective, in my opinion, is that only I have the neural connections, to/within my own brain, needed for my mind to observe myself experiencing things and having emotions. No-one else has those connections, so they cannot know what it is like to be me in the way I can. As Dennett put it, "'Qualia' is an unfamiliar term for something that could not be more familiar to each of us: the ways things seem to us.”
The argument against Jackson is not that non-propositional knowledge is not knowledge, but that it is not the sort of knowledge that can be gained by studying (not 'discursively learnable', as Torin Alter puts it), so that Jackson's claim that Mary has all the physical knowledge is being challenged.
Conventional epistemology makes a distinction between propositional/knowing-that knowledge and various other forms, such as knowledge-how, (e.g. knowing how to ride a bicycle, which you don't learn from a book), and knowing a person or a place by acquaintance. For a while, the leading response to Jackson was the ability hypothesis, which claims that, on her release, Mary gained, not propositional knowledge, but certain abilities, such as how to recognize, recall and compare colors. These are generally considered to be examples of knowing-how, not knowing-that/propositional knowledge. These days, the favorite form of reply seems to be "old knowledge in a new guise": when Mary sees colors, she does not gain any new knowledge, but sees her existing knowledge of physics in a new way. To me, this seems both implausible and unnecessary, an attempt to explain away something that already has a straightforward explanation, so I am disinclined to describe it further.
Well, no... but we can work out what a metamer is and a theory of protanopia and deuteranopia. I'm pretty sure the things you're looking for are somewhere in the visual cortex.
@Harry Hindu
Quoting InPitzotl
It doesn't approach being a proof, but, IMHO, it is a plausible hypothesis. Per my earlier post, I would not propose that everyone's experience is the same in detail, but that for most people, there is a broad degree of functional equivalence. For example, I am not a synaesthete, and so will clearly experience some things differently than those who are. I suspect, however, that these differences are at the level of iris color or hair type: for one thing, evolution is very conservative about things that are important to fitness, and our minds, and the way they interact with our environment, seem to fall into that category. For another, there is empirical evidence in a broad agreement that certain experiences are pleasant/desirable and others are most definitely not.
What arguments are there for the proposition that everyone experiences things fundamentally differently? Or do the three of us just have different intuitions about how different they are?
So? We can talk about color experiences of humans too... we agree on color categories in those 95% of individuals I described earlier. But that says nothing about the experience being the same... only that the categories are.
Quoting A Raybould
...and so is its null hypothesis.
Quoting A Raybould
...color grapheme synesthetes (for example) still see color... they're just able to associate graphemes with color. Plausible explanations for color-grapheme synesthesia are here. The existence of conditions like synesthesia only seem to beef up the plausibility of the null hypothesis.
Quoting A Raybould
I could think of arguments, but that's irrelevant. The only argument necessary for my strong defense of a non-position is that the null hypothesis is plausible (see below).
You misunderstand. I don't have a theory of similarity, differentness, or even commensurability of experiences of color. What I have, instead, is a standard... an expectation of what kinds of things I need to see before I start doing silly things like believing a thing, that no random guy with some strong opinion and bad arguments is going to get me to lower. And as unfair as it may seem to be, I expect others to meet this standard before I can grant them my approval of their conjectures.
So far the arguments I've heard for same experience is, we're the same species, and evolution selects for fitness. Okay, sure, we are, and it does, and yet I can't use that argument to prove we all have green eyes, so how are you going to use it to demonstrate that we experience red the same way? It's simply not good enough... you need an argument that actually argues for what you're arguing for.
Quoting InPitzotl
And often the null hypothesis is right! We seem to be agreed, then, that this hypothesis is both plausible and possibly correct.
Quoting InPitzotl
Firstly, I see that the word 'fundamentally' is missing from my words without having been replaced by ellipsis. If you want to claim that everyones' experiences may be different in ways that we may not agree are fundamental, then we can go with the alternative that I proposed, and simply agree to differ.
At this point, my working hypothesis is that you do not have any plausible arguments for that proposition. Your next sentence reinforced that view, and your final paragraph did not lead me to change my mind.
Quoting InPitzotl
Coincidentally, that's what I said about @Harry Hindu's point! - but plausibility itself does not come out of nothing; it needs an argument in support. A proposition without a justification states something that is conceivable, but not anything more.
Quoting InPitzotl
In scientific inquiry, theories are preceded by hypotheses. You don't have to believe them, just consider them. Of course, if there is contrary evidence rendering a hypothesis unviable, then it is summarily rejected and science moves on, but that does not seem to be the case here.
Thanks! I am surprised by the lack of attention that Churchland's paper gets, as, in my opinion, he has identified the fundamental flaw in Jackson's argument (Terence Horgan appears to be the first person to raise the issue of equivocation, but only in passing, and narrowly.) Even though Jackson himself has changed his mind on the issue, his argument is still debated (at least two English-language books were published on the issue last year!) but that debate seems to be mostly over the "old knowledge in a new guise" responses, which to me seem to be moot, given Churchland's straightforward rebuttal.
I think that most proponents of that view would say that she would be able to remember colors, compare colors, and even perform Hume's task of imagining an intermediate hue between two that she is seeing, before ever learning any names for them. It is mildly interesting to wonder if she would divide up the spectrum as we do (at which point, I must say that I have always regarded the distinction between indigo and violet as questionable!)
I just thought of something. Let's go back to this:
Quoting InPitzotl
If its possible that every one of us could experience a different color when looking at the same thing, then the scribble, "red", doesn't refer to an actual color, rather it refers the the experience an individual has of some color when looking at something. So, what would it mean for Mary to understand "red", if not that she understands that it is merely a scribble that refers to a particular experience, not a particular color, when looking at a certain object.
In this sense, apples are actually red, or wavelengths are red, in that particular wavelengths give rise to a particular experience that is consistent. So when we refer to red wavelengths, we aren't referring to a color, rather a common cause for our experiences.
several years ago I watched a documentary on the BBC in which a man was put into a fMRi machine and presented with two cards to choose from. the computer analysing his brain was consistently able to predict the choice he would make, before he made it.
for the purposes of the documentary the timing was the issue, that his brain knew before his mind knew that he would choose the cross not the circle. for the purposes of this thread, the point is that an analysable brain-state equated to a specific experience. I'm not overly familiar with the particular quandary being debated in this thread, but that Mary has a brain-state that corresponds to her experience of seeing Red does not seem to be an issue.
Kaarlo Tuomi
1. Mary at time T is in possesion of a complete theoretical apparatus that allows for the prediction of all future events, or for the QM theorists lurking, allows for the prediction of the probability distribution of all future events
2. As a matter of definition only, anyone with that kind of knowledge knows all the physical facts.
3. Lemma: from 1 and 2 Mary at time T is in possession of all the physical facts.
4. Mary, up to time T, has never seen any colours other than white and black and the 50 or so shades of grey in between.
5. Mary at time T+x sees with her own eyes a red tomato, and not by seeing a black and white image of a red tomato, nor through any other kind of technological apparatus.
6. Mary gains something at T+x that she did not possess at T.
7. Given Lemma 3 and premise 6, what Mary gains is not knowledge of a physical fact.
Premise 6 must either be denied or accepted, whether one be a physicalist an idealist or some wishy washy compromise between the two. How do we motivate that it must be accepted? "Well, put yourself in Mary's position" is the standard technique to do that. So, we imagine ourselves living in a world which really has just the colour range of old film noir, and suddenly we stumble across a red tomato, or perhaps a pair of red shoes. That might pump the intuition that our lives are suddenly richer than they were, and so we have gained something.
If we accept that intuition, and intuition is all it really is, we then face the problem of describing what exactly it is that we, and Mary, have actually gained. Here dualists/idealist and so on have the upper hand, since they have a more or less unrestricted ontological menu to choose from. Physicalists, though, need to be careful. They need to express what it is Mary gains, but they need to do that in such a way that the description falls outside of the complete theoretical apparatus mentioned in premise 1. Just to give a taste of the problem here, suppose the conversation between a phyiscalist and an early incarnation of Frank Jackson goes like this:
Physicalist: Mary gains an ability.
FJ: OK sport, what ability?
Physicalist: The ability to recognise red things.
FJ: She could alread recognise red things. Tomatoes are red things and when she was given black and white pictures of vegetables and asked to pick out the tomatoes, she had no problems.
Physicalist: That's not what I meant. I meant she gained the ablity to recognise red things on the basis of their colour, not their size or shape.
FJ: But she could already recognise red things on the basis of their colour, not their size or shape. Mary has some remarkably sensitive measuring equipment and given a room of coloured objects, on the basis of the wavelengths of light they are reflecting, and accounting for the ambiant conditions, she is able to pick out those reflecting in the 700–635 nm range, and those are usually red things.
Physicalist: That's not what I meant either. I meant she gains the ability to pick out red things just by looking at them.
FJ: Are you sure about that? What if the next tomato she sees is an unripe one and she is just using her eyes? You and I would call it green. Unless Mary can rush back to her equipment, she's probably going to lump it in with the red things.....hell of an ability she's gained there, sport.
Obviously, the physicalist will have a retort.
Let's cut to the chase, and start with one issue that seems to render everything else moot - your conclusion:
Quoting jkg20
This seems to come back to what I said earlier about equivocation over the phrase "physical knowledge":
Quoting A Raybould
I am unable to read your lemma 3 in any other light than you are making the same equivocation as Jackson here, and taking "physical knowledge" to be "knowledge of physics", as opposed to "knowledge which has its information content encoded in physical form." If this is not so, could you clarify your argument on this issue?
By the way, in 1927 Bertrand Russell penned a concise aphorism that captures what you are saying here (if I have not misunderstood you), and also the essence of Jackson's argument:
It is obvious that a man who can see knows things which a blind man cannot know; but a blind man can know the whole of physics. Thus the knowledge which other men have and he has not is not a part of physics.
As far as I know, Russell never regarded this as a refutation of materialism, and rightly so, as to mistake it for such would also require the same equivocation.
Essentially yes, but...
Firstly, we must recognize that people have been talking about colors for millenia, and, for the most part, doing so without having any theories about how the perception of color works (or, in some cases, demonstrably false ones).
As I mentioned elsewhere, language depends on a common vocabulary, and common vocabularies ultimately depend on shared experiences. We do not have direct access to what is going on in other peoples' brains, and not even to what is physically going on in our own. Nor can we directly sense the wavelength of the light we see or the energy of its photons. About the only shared experience of color comes from people looking at a given thing (say, a ripe tomato) and agreeing that a certain aspect of that experience should be given a name, such as 'red'.
For this to work, several conditions must be met, such as:
...and so on. Given that not everyone is able to join in this agreement, it seems that our being able to come to a broad agreement over these issues is a contingent fact, and that it is conceivable that this might not have been so.
This is where my database analogy comes in. It is completely implausible that most of our brains are identical at the neuron level, yet still we meet the conditions of the above list. In my opinion, we are like the ordinary users of the two databases, who can agree that their databases contain the same information, even though the two databases have almost no physical state in common. For the purposes of the ordinary users, who use the databases in performing tasks in the external world, the physical state is irrelevant. Only the system admins have any reason to be concerned with that state, and when we debate the nature of the mind, we are, as it were, logging on as administrators.
---
The takeaway from this is that almost nothing about how the mind works can be clarified or settled by arguing over the definition of the words we use to label our experiences, because those words were coined operationally, in ignorance of the underlying processes.
Your working hypothesis doesn't work.
Did you bother to try? At the highest level of abstraction this seems incredibly simple to me. We just postulate that there's a large number of potential experiences and that the brain, while learning to see colors, simply picks any of these to bind to the interesting categories. Synesthesia demonstrates that there are different kinds of experiences to pick from, and that they can at least be useful in some people as category tags even cross-sensually. My natural response to this is, if there are this many kinds of experiences, how many can there be? Incidentally, what made you make up your mind in the first place such that it would need to be changed?
Quoting A Raybould
But the argument here is, at least IMO, trivially made. The arguments given for same-experience to me sound like classic textbook hasty generalization. It seems you're describing an approach that is particularly vulnerable to argument from personal incredulity, and is way too quick on the belief button for my tastes.
(FYI, there's a lot of other stuff you're saying I've no problems with; it's just that I'm only going to pick on where we conflict).
Quoting InPitzotl
All the evidence to that point (notably, the absence of any argument) supported it.Whether the situation has improved with your latest post remains to be seen.
Quoting InPitzotl
That's not an argument, it is an opinion. Furthermore, it is an opinion of an argument, not an opinion about how minds work. You are as entitled to your opinions as the rest of us, but don't expect anyone to find anything like this, doubly removed as it is from being an argument for a substantive claim, to be persuasive.
Quoting InPitzotl
I am amused by the fact that your only substantive argument in this whole reply makes use of one that I first introduced to this discussion! Note that I was prepared to introduce a counterpoint to the position I favored, and that is because I am interested in getting to the truth, not in scoring points in some minor debate. Your question, "did you bother to try?" is best addressed to yourself.
Quoting InPitzotl
What does 'binding' mean? How are 'interesting' categories determined?
Furthermore, with "a large number of potential experiences" to pick from, unless the picking is done in some principled manner, one should expect that utter chaos would result, with people unable, for example, to agree even on what sorts of sensory perception there are. In practice, we find broad agreement, with only a few corner cases, such as the synesthesias that I mentioned, to hint of the potential chaos. How, in your theory, do you resolve this issue?
I'm in way over my pay grade here. I'll just say that I'm a big believer in the importance of qualia to any theory of mind, and opposed to those who say you can have intelligence without self-awareness. I'm sure I'm muddling many philosophical issues.
You're really missing the point. "Evolution is conservative therefore we all experience redness the same way" is also an opinion. Opinion dismissal is no justification for another opinion; all opinions should be held to the same standard, even if you happen to hold one of them.
Quoting A Raybould
Not... exactly. This is a guideline to applying relevant standards. You're arguing about differences and similarities of experiences between humans, under the presumption of a physicalist interpretation. So let's start here... is there reason for you to disagree that the key factor to look at here is the neural correlates to experiences?
Quoting A Raybould
But convincing you isn't supposed to be the goal. The goal is supposed to be applying a valid truth criteria. In this case, the criteria of truth should have something to do with neural correlates to experience... would you agree?
ETA:
Quoting A Raybould
Binding in this case simply means creating some sort of stable state at some layer in the network; "interesting categories" can be self-discovered by features of the net analogous to how deep neural networks work. I'm not too interested in fleshing out this theory since I don't particularly subscribe to it... I'm more interested in gating the justifications to the things that they're supposed to be including (here is an ancient video including presentation of self-discovered categories using deep neural nets; but here is a link to a paper discussing the kinds of things I think should be included in any speculation).
The only thing that was to the point in your previous-to-last post was that you finally put up an argument (or, rather, the outline of one) in support of the position you have been taking: viz., your insistence that it is simply not plausible that sensory experience functions in a similar manner for most of us.
Quoting InPitzotl
It is not clear to me what you have in mind here, though it seems to be suggesting a chaotic process - but whether that is so may depend on what you have in mind when you say "a large number of potential experiences" (do you mean the totality of an individual's sensory inputs at any given time? Are emotional states included? Conscious thoughts?), on what basis you envision the picking to be decided, and how the categories are chosen for binding. At least until you explain these matters, it is not clear to me that you have a viable argument for your position.
Indeed. That is achieved by measuring something called 'voxels' which depict oxygen consumption and other parameters of brain activity. It's heavily dependent on predictive algorithms which are used to validate the presumed correspondence between various cognitive acts and the associated neural activity. So it's not difficult to see issues with confirmation bias and the like in this kind of scenario.
See Do you believe in God, or is that a software glitch?
To add to my previous rushed response, even if we admit that one gains the ability to remember and compare colours, it is unclear how or whether this is a gain of knowledge of any sort. What knowledge-that or knowledge-how does one gain from this purely mental ability? How might one prove that they are able to remember or compare colours?
Why would you need to appeal to chaotic processes?
Quoting A Raybould
Start simple. Imagine we develop a fourth cone type and manage to develop tetrachromacy.
Quoting A Raybould
You're making the wrong appeal to the wrong person. I'm not playing the debate game; in fact, I'm skeptical of that entire game. Convincing you isn't the prize I'm after. Tossing that away, the only reading of that statement left is that you're declaring dependence upon me to question your premises for you, which I read as a bad thing.
that was an extremely interesting read. the dead salmon is both very funny and extremely frightening at the same time.
thank you
Kaarlo Tuomi
Purely by chance, I noticed that you added a postscript to your last-but-one post after I had replied to it, in which you offered some sort of response to my requests for clarification of something you had postulated. I'm prepared to put that down to concurrent editing, but there are some unusual aspects to that response.
For one thing, you say "I'm not too interested in fleshing out this theory since I don't particularly subscribe to it", which is rather an odd thing to say about something you had postulated only a few hours before as if it were a strong argument for your position. I will assume that you were not disenchanted with it at the time you first postulated it, as to put forward a view that you did not actually hold, without making that clear, would be quite deceptive, so it seems that you changed your mind during the time when I was probing its relevance. How long, I wonder, would you have left me under the impression that you still held that view?
You also added links to a video and a paper, and the latter, at least, does seem to have some relevance (Categorical encoding of color in the brain)
Here we have an experiment using functional MRI to study the responses of a number of subjects to sensory stimuli. This is a very common sort of experiment, yet If it were the case that everyone's responses to stimuli were more-or-less unique, such studies would fail to produce consistent results. Not only do they do so, but the whole tenor of the paper (and others like it) is infused with the tacit assumption that this commonality in function is a fact of how brains work - there is no hand-wringing over whether the subjects will be similar enough in their responses to justify the approach, and I would bet that the possibility that it would not be is rarely an issue in the funding of such experiments.
This, of course, is commonality at the level of abstraction probed by functional MRI, which does not prove that the commonality must hold at higher levels of functional abstraction, but it certainly does not suggest the contrary. You have already accepted that hypotheses do not have to meet the standards of evidence needed to be classed as theories, and that you don't have to believe them to consider them.
As for your examples of synesthesia and tetrachromacy, it is not unreasonable to consider them as second-order effects. I don't think many papers reporting this sort of work contain the caveat that their results cannot be extended to these cases.
Given the results of this experiment, perhaps you consider color categorization to be a counterexample to the hypothesis that most people's responses to stimuli are broadly similar?
Quoting jkg20
Well, if you haven't reached the conclusion that physicalism is false, then you have not completed your task of, as you put it, circumventing Churchland's attack [1]. Jackson makes no bones about the goal of his argument: it is to demonstrate that physicalism is false, and Churchland's response says that it fails to do so.
Churchland accepts the premise that Mary has all the knowledge that Jackson claims she has, and also that she learns something new after her release, but this presents no challenge to physicalism, because what she learns afterwards is not within the set of physical knowledge as defined by Jackson (and you), and physicalism neither depends on nor implies that it should be.
Churchland uses Jackson's equivocation over "knows about" to make this point: all the knowledge Mary gains from her studies must be propositional (she is being denied any opportunity to learn about color by any other means, such as experience), while it is entirely plausible that what she learns afterwards is not propositional. In the paper, which I urge you to read, he makes a biological argument for the plausibility of this new knowledge being non-propositional (one of the things he points out is that there are a great many species of animal having trichromatic vision, and for which, therefore, there is presumably something that is "what it is like" to see colors, but do not have language; presumably, they are not believing in propositions of any sort.)
Churchland also makes a point that people often get wrong: he is under no logical obligation to provide a complete and factually correct account of exactly what Mary would learn on her release. While that would be one way to refute Jackson, there are others, and showing that the argument is invalid is how Churchland does it here. As Jackson is claiming to have proven that physicalism is false, he has assumed the burden of showing that there is no way it could be true (to this, I would add the point that no dualist has ever given an explanation of how their alleged non-physical aspects of minds work.)
As Tiim Crane has pointed out, the issue of validity can be turned into an issue of soundness, by adding a further premise, such as "after her release, Mary gains propositional knowledge about color vision." Unsurprisingly, Jackson, who overlooked this issue, made no argument for it.
In retrospect, Churchland was not as tightly constraining as he could have been, and by calling Jackson's "all the physical knowledge" propositional, he encouraged some dualists to claim that Mary might learn something propositional on her release. As they have not been able to say what that is, despite the fact that there have been billions of people who are both language-capable and know what it is like to see colors, I doubt it.
This is moot, however, as, whatever else Mary's physical knowledge is, it must be something one can learn from books or lectures (Alter calls this 'discursively learnable.') The additional premise, then, becomes "after her release, Mary gains discursively learnable knowledge about color vision." This puts dualists on the horns of a dilemma: Unless what she learns on her release is discursively learnable, Churchland prevails, but if it is, then how come she did not learn it from her studies? It would be begging the question to just assert the premise that it must be nonphysical discursively-learnable knowledge.
Note that Jackson never equivocates in the sense of saying, in one place, that "learns about" means this, and in another place, that it means something contradictory to that: it is, instead, implicit in how he uses the phrase. He does essentially the same, or so I propose, with the phrase "physical knowledge." He (and you) define it esentially as "knowledge about physics", and if Mary learns something on her release, it cannot be physical knowledge, therefore physicalism is false. It is in the "therefore" that we have a false implicit premise, which is that, as this new knowledge is not knowledge of physics, physicalism must be false - but physicalism neither implies nor depends on all knowledge being knowledge of physics. The English phrase "physical knowledge" is ambiguous, as, in addition to this reading, it might also be read as "knowledge, where the information content is encoded in physical form", but Jackson's argument cannot just be restated to use that definition consistently, as one would be begging the question to assert that what she allegedly learns after her release is not in that category.
[1] Update: As soon as I posted, I realized that you probably meant that your argument went beyond proving that physicalism is false. Unless it succeeds at that, however (and I do not think it does), then anything else that follows is moot.
Quoting Luke
If it is not knowledge, then Jackson's argument fails, because it depends on her gaining knowledge that is not in the set of "all the physical knowledge." More conventionally, it is regarded as a different sort of knowledge: knowing-how instead of knowing-that. As Jackson's concept of physical knowledge is of the knowing-that sort, physicalism is not challenged by her new knowledge not being part of it.
Quoting A Raybould
Ah, I see why you were confused now. But I think maybe you want to read this post a bit more carefully before suggesting that I might have misled you.
Quoting A Raybould
Nope, I did not change my mind. I still say that "evolution is very conservative about things that are important to fitness, and our minds" is a bad argument for same-experience theory.
Quoting A Raybould
This sounds a bit fishy to me. It sounds like you're guessing that the researchers secretly agree with you, "betting" that they do, and then appealing to this secret agreement.
Quoting A Raybould
But hang on, that's the wrong take-away. Let's focus on tetrachromacy a bit more... if a human develops tetrachromacy, would you think it reasonable that said human would have more color experiences? I mean either it's that, or somehow the same color gamut just gets "redistributed", or we just happened as human trichromats to max out on the number of potential color experiences (or, supply your own other?) If tetrachromacy does lend to more color experiences though, then there are indeed more potential color experiences to be had. So the next question to ask is, do we need to add more stuff to the brain in order for it to be able to have these additional color experiences, or would the brain somehow wind up with them if we had four cone types giving us richer information? We could ask the same question on lower levels (e.g., how the ganglia forming color opponent channels in the retina would organize), and that leads to questions about, gee, how do they organize anyway, in us trichromats?
Do you see what I'm getting at? None of this actually argues for different-experience, but you certainly can't just handwave same-experience without understanding how this stuff works in the first place. All of these are good questions, and they really require more study.
Quoting A Raybould
I think that question is making assumptions that are not yet justified. A response to a stimulus is behavioral. What effect would having different kinds of experiences of similar stimuli have on the behavior? If I experience red a different way than you experience red, wouldn't we still both call red things red?
Yes, I agree.
One can circumvent objections by changing the argument, which is effectively what I did: it is certainly not Jackson's original argument. It is an argument that essentially states that if you accept that Mary gains anything epistemologically, you are obliged to give an account of what she gains, and the account given must not result in Mary getting something that she already had or could have obtained without seeing the red tomato.
I agree that there is some unclarity about what physicalism is, you mentioned Tim Crane, and one of his earlier papers was on exactly that point. I tried to encapsulate a rough approximation of physicalism, and let me try to be less circular by saying that Mary having complete physical knowledge would give her the apparatus to predict every measurable event in the world, given knowledge of the measurable starting points. Measurable here means measurable by apparatus available to anyone. So, when Mary sees, at time T+x, the red tomato, she is in some overall measurable state. At time T she is able to predict accurately the measurable state she will be in. Let us suppose she does this, i.e. at time T calculates all the measurable effects on her and her environment of her coming to see a red tomato without the aid of optical equipment. She will write down a number of statements such as "At T+x my cones are excited in such a such a way", "At T+x+dx my optical fibres are excited in such and such a way", "At T+x+dx+dx my frontal lobe will be excited in such and such a way" and so on and so forth. At T she has this entire set of time indexed propositions covering the moment she is confronted by the red tomato up to, let us say, two seconds afterwards. We make the assumption also that any abilities she has at T+dx are also included in this set of propositions, perhaps in the form of conditional statements of the kind, if at time T+dx+dz I am again confronted by a red thing, then such a such a measurable effect will be observable. She needs no confirmation of the truth of these time indexed propositons, because her theoretical apparatus is complete and true. I.e: she knows all these propositions.
The question now is, given that Mary is in that position, does she still gain anything epistemologically at all when she sees the red tomato? That she does is based on the intuition pump, but we do not have to accept intutions, which are after all not much more than guesses. It is a question for the idealist and dualist as much as it is for a materialist monist. The materialist monist has the luxury of responding "no", and thereby rejecting the intuition, but I suppose then has to deal with the persistence of the "illusory" intuition that Mary would gain something. The idealist and dualist must really respond "yes" and, as you hint, need to say something about what she does gain, which usually leads them into hand gesturing about qualia and so forth. However, the materialist monist who responds "yes" also needs to say something about what Mary gains epistemologically and what she gains must meet some criteria. The first of these is, of course, that whatever is proposed should not already be included in the set of all the time indexed propositions previously mentioned, since otherwise it is not something she gains epistemologically. The second is that whatever is proposed is genuinely something epistemological in nature. This is where, presumably, a materialist monist might want to try suggesting that Mary gains some measurable abilities. The problem then is to state what those abilities are in terms that do not quantify over anything not quantified over in Mary's theoretical apparatus, and is also an ability she genuinely gains that is not included in the set of propositions covered earlier. Faced with that, the materialist monist might point out that the assumption was that the set of propositions included all conditionals covering all the abilities that Mary has at time t+x, so the challenge to provide an new ability she gains cannot be met. Fair enough, so either the materialist monist back tracks and says that Mary does not gain anything epistemologically when she sees the red tomato, and so face the question of accounting for the illusory intuition that she does and its persistence, or the materialist monist tries to come up with some other kind of epistemological gain Mary makes that is not based on her gaining abilities or propositional knowledge. FOLLOWING SENTENCES ADDED: Or perhaps the materialist monist might try to deny that abilities can be reduced to conditional propositions the truth of which can be determined by taking measurements. But that looks like admitting that there are abilities that we have that fall outside of the scope of Mary's theoretical apparatus.
Quoting InPitzotl
I think I do, and I think we are talking at cross-purposes. You are saying that these differences exist, and I am saying that they are second-order effects, modifying an underlying commonality. We could both be right! (Or wrong.) Alternatively, we could just agree to disagree in our opinions and wait for neuroscience to achieve a more fine-grained picture than fMRI and related technologies has delivered so far.
BtW, I recall seeing some fairly convincing evidence (some variant of the Ishihara test), a few months ago, that a small percentage of women are functional tetrachromats, having two different yellow-detecting pigments, but I do not recall where I saw it.
Quoting InPitzotl
Not necessarily - it seems quite possible that, while we might agree that certain things are red, we might not agree on others. Of course, people do sometimes disagree over subtle distinctions in hue, but that is what I would call a second-order effect.
Quoting jkg20
The question of who bears the burden of proof (or accounting) is not always clear-cut, but in this case, I think Churchland's response, especially when put in terms of what is discursively learnable, puts the burden squarely in the dualists' court. I think this is most clear when we adopt Crane's third premise, again put in terms of what is discursively learnable: "After her release, Mary learns a discursively-learnable fact about color." A dualist could simply assert that this is so, but doing so would not put us under any logical obligation to accept it, especially as we could ask the dualist why, if it is discursively-learnable, Mary could not have learned it before her release. If she could have done so, then the premise that she must learn something new does not hold.
Also, as I have pointed out elsewhere, no dualist has ever given an account of what non-physical whatever-it-is Mary supposedly gains.
As it happens, however, I think physicalists can give a very straightforward account of why she could not learn, beforehand, whatever she learns from seeing colors. As you propose, Mary, knowing everything that could possibly be known about the physics of color perception, will be able to figure out what changes will occcur in the physical state of her brain as a consequence of any particular color-vision experience. According to the physicalist premise, these changes, and these changes alone, bring about Mary's new knowledge, so all she would have to do, while isolated, is to make those changes happen to her brain state, and she would then know, say, what it is like to see red (or whatever she would learn from the specific experience for which she has worked out what it will do to her brain.)
Knowing what those changes are, however, is not enough to make them happen. Our brains are simply not connected in such a way that we can address individual synapses and make specific changes to their state. Mary has all the knowledge she needs, but lacks the means to put it to use.
In this view, what she learns from seeing colors is physical knowledge in one sense: knowledge in which the information content is in physical form. It is not physical knowledge in the other sense of being a true proposition about the physical world (anything that is, she already knows.) The physical knowledge, of color vision, that Mary can learn while isolated, is limited to things of the latter form, so there is no problem for physicalism in Mary gaining physical knowledge in the former sense afterwards.
This is actually a contingent fact, as it is possible that, at some time in the future, we will develop the technology to make those targeted changes to our brains. With such a device, and Mary's physical knowledge, she could come to learn what color vision is like, without having experienced it (the experience of using such a device might be quite unusual, perhaps like the experiences of those people who must be conscious as brain surgery is performed on them.)
Update:
As far as I can tell, these objections work just as well as a response to your argument as to Jackson's. If I am not mistaken, the major difference between them is that you say that Mary's complete knowledge means that she can infallibly predict the future. This takes us into the murky waters of determinism and causality: if she can predict what she will know in the future, why can she not know it now? (Especially as, by premise, it is propositional.) It would be begging the question to say that she cannot do this because it is nonphysical knowledge.
https://en.wikipedia.org/wiki/Tetrachromacy#Humans
I have to say though... it's a bit interesting seeing this called a yellow-detecting pigment.
Quoting A Raybould
I'm a bit lost. You're now speculating that there are behavioral differences?
I think it is sometimes called 'yellow' (if I am recalling that usage correctly) because it is a variant of the more common green opsin, with a spectral response shifted towards longer wavelengths.
If two people differ in their experience of a class of stimuli, is there any reason to be certain that they will be able to come to an agreement on how to categorize them? (Though it would be easier for them to do so if they were merely second-order differences.) We don't learn what 'red' means by memorizing a canonical chart of all the hues that are red. And there are behavioral differences: for one thing, tetrachromats behave differently than most of us in the tests that demonstrate their particular talent.
That actually describes erythrolabe (the L opsin). (I'm not saying anything's wrong here BTW, just that it's a bit interesting to hear talk of yellow-sensing cones)
Quoting A Raybould
Is certainty an appropriate burden for some purpose here?
Quoting A Raybould
The color categories are in large part shaped by cone properties. Metamerism for example is an expression of different spectra that have the same effects on the cones.
Quoting A Raybould
Now I think you're lost. We're talking about two trichromats with similar cones potentially or not as the case may be having different kinds of color experiences. Tetrachromacy comes into play here only by comparative speculation that there might be different modes of experiential color than the ones trichromats have, which suggests different potential experiences.
It depends. It seems to me the materialist monist would have to reject the premise of my argument that Mary does gain epistemologically when she confronts, or is confronted by, the red tomato. That's an option of course, and one which towards the end of your post, you hint at. However, I am still unconvinced that the materialist monist can accept the premise that Mary gains something and offer a response to the question what. You write:
"According to the physicalist premise, these changes, and these changes alone, bring about Mary's new knowledge,"
You seem to agree that what Mary knows prior to the event includes all the changes referred to, so what is Mary's new knowledge that is brought about by them? Is it an ability, is it some new set of propositions, is it some other kind of knowledge? That question does not seem to be answered in the paragraph of yours I extracted that quotation from. You mention only that the physicalist just needs to point out that it is information encoded in physical form, but what is that information?
As to your burden of proof point, I was attempting to give the basis of an argument that avoids tossing the burden ball. As I say, there is a burden just as much on dualists to give a substantial account of what is learnt by Mary. Idealists as well would need to say something, but would probably opt for denying that Mary gains anything and instead say that the intuition that she does gain anything is based on a false understanding of what it is to know all the physical facts, something that the materialist monist could also try. In any case, idealists have different tricks up their sleeves and don't generally, at least as far as I am aware, use Jackson's argument, or any variant of it, at all.
Regarding the definition of physicalism I gave, you are correct that it requires Mary to have the theoretical apparatus to predict, with appropriate statistical distributions where necessary, what events will occur in the future. For sure this raises issues about determinism, but that one area of metaphysics should have a dependence on or be related to another area is no big surprise: it is probably only in professional analytic philosophy circles that anyone pretends, or has to pretend, that metaphysics can be cut into bite sized chunks. I suppose it might be said that my argument requires that the timeindexed propositions that Mary knows at T can only involve statistical distributions of event occurrences, and that at time T+x the distribution curve collapses to a point and so Mary comes to know a proposition without any statistical hedging, which she could not have known before. Not clear to me if that would help the materialist monist though, I'd have to think about it.
Quoting InPitzotl
Feel free to reply at the greatest confidence level you think can be justified.
"Justified" isn't the point. Purpose of holding this burden is. Usually when I see the certainty burden it's an indicator of a double standard of burden of proof; one holds some opinion A and then one adopts a "prove me wrong" view, with the naive idea that they're open minded because they will consider other opinions, but the pragmatic idea that they hold opposing opinions to A to a much higher standard than opinion A itself. What I'm questioning isn't what burden can be met, but why you are applying this burden.
FYI, I already listed (response to very next quoted snippet) reason to suspect agreement; I'll back fill this with more detail for you some time later when I get time if you like.
Quoting InPitzotl
I eagerly await your explanation.
It is clear that before we can complete the discussion of your argument, we have to resolve the issue of what would count as an effective counterargument. I do not think I am misrepresenting you when I paraphrase your position as being that a physicalist must either reject the premise that Mary learns anything on first seeing colors, or must give a full (or almost complete) physical accounting of what she does learn.
This is simply not so. A physicalist can alternatively accept that Mary does learn something, but show that it is beside the point in one way or another, and one way to show that is to make a plausible case that there could be some explanation for why Mary had not learned it beforehand, that does not challenge physicalism - and that's what most of Jackson's opponents do seek to show.
This sort of thing is common in all fields of incomplete knowledge. For example, in astrophysics, the rates of rotation of galaxies seems inconsistent with what we know of gravity. There are at least two putative explanations: MOND (gravity works differently at long range) and dark matter (there's something we haven't seen yet adding to the galaxies' gravitational field.) Suppose someone says that the rotational data proves MOND. When a skeptic says that dark matter is an alternative possibility, simply saying "so prove me wrong" would not be a reasonable response from the first person, and demanding that the skeptic must say exactly what dark matter is would amount to that, and would be a clear case of burden-shifting. The rational response to the issue is to say that we have these hypotheses, and have not yet figured out what is going on. Jackson is not saying this about the mind; that is not even a point that needs arguing. In his initial paper, he literally claims to have proof of the falsity of physicalism (a position that he subsequently backed slightly down from, and then reversed entirely.) If you are merely saying that physicalists have not yet presented an explanation of the mind, then there are much easier ways to make that point, if you can find anyone who disputes it.
Let's look at it another way: one of your premises is that Mary knows enough to predict the future in every physical detail, but what, exactly, does she know? It would be inconsistent to consider a lack of a complete explanation to be an objection to the premises of responses, but not to your original premises.
This is not just my opinion; this is how philosophy (and science) works. This is what Churchland said:
"The view sketched above is a live candidate for the correct story of sensory coding and
sensory recognition. But whether or not it is true, it is at least a logical possibility.
Accordingly, what we have sketched here is a consistent but entirely physical model (i.e.,
a model in which Jackson's conclusion is false) in which both of Jackson's premises are
true under the appropriate interpretation. They can hardly entail a conclusion, then, that
is inconsistent with physicalism. Their compossibility, on purely physicalist assumptions,
resides in the different character and the numerically different medium of representation
at issue in each of the two premises. Jackson's argument, to re-file the charge, equivocates
on 'knows about'."
This is far from the only thing I have to say about your previous reply, but I think we need to deal with this one first.
Okay, so since we keep going back and forth over this point, I've cobbled together the following illustration. Here's a color optical illusion based on Beau Lotto's famous cube illusion:
[hide="Reveal"][img=c]https://i.ibb.co/YXmZ3rJ/fauxlotto.png[/img][/hide]
Here, the two color swatches on the large cube indicated by the corresponding color swatches on the gray cube are the same color.
This diagram illustrates three different layers of "color"... layer L0 indicates the physical spectrum. Layer L1 is what the cones in your eyes resolve (what I'm calling here colorimetric). Color experiences occur in this diagram at layer L2. The reason for using this illusion is to highlight that L2 colors are distinct from L1 colors, because certainly since these two indicated swatches are the same color spectrum (L0), the cones in your eyes would respond the same way (L1), so any difference you see (experiential) is upstream (in our discussion so far I keep getting the impression that you're confusing L1 with L2).
L2 colors, mind you, cannot distinguish something if L1 cannot distinguish it (under the presumption that our eyes are actually serving some sort of purpose... that we're not just psychically sensing color independent of our cones). We should for example expect the same color illusion works the same way if we replace the L0 color here with a metamer (another spectral color that our cones cannot distinguish). Likewise, it appears to be common that whatever color experiences we actually have, behaviorally we tend to sense that the L1-colors (in say CIELAB space) seem to vary naturally according to variances in our experiential L2 colors.
Now get back to the hypothetical tetrachromat. A tetrachromat's L1 color space should be expected to be 4 dimensional just as us trichromat's L1 color spaces are three dimensional. Under the presumption that tetrachromacy works similar to trichromacy, we would expect some 4 dimensional CIELAB-like L1 color space; some trichromat metamers would be distinct L1 colors for such tetrachromats. In this 4D-CIELAB space we might presume L2-colors to vary roughly according to the L1 colors, but there would also be more L2-colors. Presume then as a rough model that we take a 3D slice of this 4D L2-color space that roughly corresponds to one trichromat's L2-space. Would we not be able to take a different 3D slice of this 4D L2-color space and have a second trichromat have this as his L2 colors, and still have the property in both individuals of having each of their L2 colors vary continuously in correlation to the 3D L1 color spaces?
But the arguments, Jackson's and mine, are based on the idea that Mary's knowledge is complete, at least complete insofar as to make any examples of epistemic gaps drawin from the current state of physics/chemistry etc irrelevant. Of course the current state of science is far from complete. One way of expounding on what that incompleteness means is to home in on the idea there are observable phenomena that our uncontested theoretical apparatuses do not allow us to predict as being observable. Hence my definitions of what it would be for Mary to have the complete knowledge required of her.
I think I allowed myself to be misrepresented, since if you are saying that the two premises of my argument concerning what it would be to have complete physical knowledge are up for grabs as well, sure, I'll concede that. None of the premises are a priori truths. In fact I think I suggested that some idealists would home in on challenging what I am saying would count as complete physical knowledge. I think I can see how an idealist might try responding, but what of a materialist monist? Would the objection be that physics and the other special scienses will never reach completion?
The point is that if a materialist monist responds along the lines that Mary gains something, then when asked "what" just replies something that is physically encoded but we do not yet know, then the fact that we do not yet know it is irrelevant, since the argument rules out Mary having such gaps, or attempts to. If, on the other hand, a materialist monist says Mary now knows what it is like to see red, and that knowledge is physically encoded, then that means there is some set of propositions about Mary's physical state which describe what is encoded, and so expresses what it is she comes to know. But by hypothesis Mary had the tools at T to predict that those very propositions would be true, with a given range of liklihood perhaps, at time T+x, which puts strain on the claim that she has gained any knowledge. I suppose there is the avenue to explore that she gains extra confirmation of the truth of the time indexed propositions, although she did not need that confirmation. Althernatively, as I put it in my previous post, she gains knowledge that the probability distribution has collapsed onto a specific member of the set of possible propositions.
Anyway, either complete physical knowledge is possible or it is not. If it is not, and the admission of this has been forced on the basis of arguments involving people coming to know things when they see things for the first time, then dualists have it. If it is not possible for other reasons, then dualists still have work to do. If it is possible to have complete physical knowledge, then I suppose we need to agree on how exactly to spell out what that would mean. I proposed glossing it in terms that provide the tools to predict all observable events, but maybe there are better alternatives.
Editing my own post and specifically concerning this remark
" then that means there is some set of propositions about Mary's physical state which describe what is encoded, and so expresses what it is she comes to know. "
I suppose there is a riposte here that what is encoded can only be stated as knowing what red looks like, and that there is no alternative way of expressing that content, but that admitting this does not entail that the content is not encoded physically. Of course, accepting this might involve having to buy into a representational theory of mind, which personally I do not, regardless of any issues about this knowledge argument. However, regardless of that, is that riposte really available for a materialist monist? If the content encoded can only be expressed as "knowing what red looks like" then there could be no identity expression of the kind "knowing what red looks like is identical to ........ " where ........ must be precisely an alternative way of expressing that same content. You might want to say that materialist monists do not need to make such identity statements, but their monism, in the end, probably does require them to do so. One could be eliminative, but in which case there is no such thing as "knowing what red looks like" anyway, so the eliminativist would simply be rejecting the idea that Mary gains anything when she see a red tomato.
Quoting jkg20
Jackson (and also you, I believe) are actually arguing that Mary's knowledge, at the time of her release, is incomplete - but any response along these lines is missing the point of my analogy. It is a simple fact that no-one (neither monists nor dualists of any type) have complete knowledge of how minds work (if any faction did, the issue would be settled.) Given this, then not only is it is inconsistent to rule out one side of the debate on account of its proponents' inability to give a full accounting of how minds work, it is doubly so to accept the view of side that claims to have proof, despite their not being able to give such an accounting, while rejecting the claim of those who merely say that it has not been proven, on the grounds that they cannot provide a full accounting. Until we can get agreement on what would constitute an acceptable response, there is no point in discussing the merits of any argument.
It would be really useful if, in your next reply, you could address this issue alone, as I am not going to re-state the counter-arguments to any other point you make, only to have them once again rejected for a bogus reason.
Nevertheless, I think we can trim the range of issues to be covered.
Quoting jkg20
Personally, I don't think your concept of complete physical knowledge is incoherent, or inconsistent with respect to the way you define it (and the same goes for Jackson's); my point is that "physical knowledge" is an ambiguous phrase, and your definition is not the one that leads to a challenge to physicalism, should Mary learn something more on release.
As Crane points out, this is a thought experiment, so improbable things are allowed, and if you object to the impracticality of achieving this knowledge, you are simply not engaging with it.
Quoting jkg20
This is a very common and deep-rooted misconception. It simply is not the case that knowing all the facts, about the physical state of one's brain when one has some particular knowledge, is the same as having one's brain in that state, and physicalists can reasonably propose that unless one's brain is in that state, one does not have that knowledge.
Of course, if that knowledge is not propositional/factual, then there is obviously no way that facts about that knowledge are that knowledge, but even if we limit ourselves to factual knowledge alone, propositions stating facts about something we know are not the propositions comprising that knowledge itself - but I do not think we need to consider the propositional case further, anyway:
Quoting A Raybould
Firstly, thanks for taking the time to put together a well-argued case.
I cannot imagine why you think I am confusing L1 and L2, but there is nothing to be gained by following that any further.
Last things first...
Quoting InPitzotl
Possible? Certainly. Likely? I was already of that opinion, based broadly on the sort of evidence and argument you are presenting here. Necessary? No; if we are going to suppose that everyones' experiences of color are different, without any constraint on how different they might be, then we cannot assume continuous variation, let alone any isomorphism between individuals, or even any stability within a single individual.
You had asked "If I experience red a different way than you experience red, wouldn't we still both call red things red?" and my reply was, and still is, "Not necessarily." The point here is that the assumption, that we would both agree about the redness of all (or most) things, is predicated on assumptions about our experiences being similar. I am not saying that these assumptions are unreasonable (quite the contrary, in fact; I am making the same assumptions in my own point of view); I am saying that these assumptions are being made.
And what are we basing those assumptions on? The observed behavior of people (including statements about their experiences) and what knowledge we have of the physics of visual perception! It seems we can make informed guesses, about how the experiences of different people are likely to be similar, from these sources.
It's because you keep talking about behavioral responses and disagreements on whether all people would agree that particular things are red if they simply have different L2 colors but share L1 colors.Quoting A Raybould
But hang on... that, too, is the wrong takeaway. There are arguments for same-experience that you have not yet given. There are also counterarguments to those arguments. But in the end you still wind up at my position... that we simply need more study.
Quoting A Raybould
The how-different is irrelevant. There are two vector spaces, and you can map them up linearly or non-linearly (pre-adjustment of the sort we see in the cube). Our L2 colors appear to align more or less linearly. There's an implied hypothesis that the mapping would be linear. I get the impression that you somehow think that the very linearity of the L1 to L2 mappings critically depends on what the basis vectors in the L2 space represent.
Quoting A Raybould
Wrong. For us to agree about the redness of all (or most) things, the only thing that is necessary is that we form the same categories of L2 colors that vary in the same way to L1 color spaces; it is entirely unnecessary that the L2 colors themselves be the same. The presumption that our experiences are similar is not yet warranted. Given Jane is a tetrachromat, we could have j-red, j-green, j-blue, and j-c4. Your "red" could be j-c4; my "blue" could be j-c4 (incidentally, these are just simplified illustrative mappings). Also, obviously, we don't actually agree that our L2 colors are similar (your phrasing, "our experiences being similar")... otherwise, philosophers wouldn't brandish about terms like "inverted spectrum".
Quoting InPitzotl
That's my point about your argument - you are making assumptions - assumptions that say "our experiences have these similarities".
Quoting InPitzotl
Equally for your assumptions. You are being inconsistent. You are also "straw-manning" me in suggesting that I think otherwise.
ETA:
Quoting InPitzotl
Please explain how the conclusion follows from the premise.
Quoting InPitzotl
While you are about it, please explain how that follows, also.
Try to pretend for a second that you understand math. Abstract the nature of experience out and let's talk about pure vector spaces. One example vector space would have a certain amount of salt mixed with a fluid; a certain amount of glucose, and a certain amount of alcohol (note that we're not concerned with infinite vector spaces, since color space is restricted to a range, so this works perfectly well). We could encode something like CIELAB (x,y,z) as distinct concentrations of salt, glucose, and alcohol mixed in the fluid. We could also swap out glucose with maltodextrin. (NOTE: There's no proposal here that experiences are solutions... I'm just showing you just how wild and arbitrary you can get when creating a vector space; outside of this parenthetical, precisely because it's arbitrarily wild, I'll come back to solution-theory of experience as a proxy). As another example, we might encode color as an oscillating function of some value varying in time, like a sound wave... x's basis could be assigned to 10kHz oscillation, y to 8kHz, and z to 7kHz, such that we have a color encoding of f(t/2pi) = sin(10000t)x + sin(8000t)y + sin(7000t)z. We might consider swapping x's basis from a 10kHz frequency to a 12kHz one (along these lines, we can also choose phase encodings or any of a number of things). I could invent vector spaces here all day long.
You've invented some sort of abstract vector space where linear correlations are no longer linear correlations, such that something would be "more consistent with [vector bases] being similar than different", but that is incoherent gibberish to me. The linearity of our mapping to saline-glucose-alcohol solution has absolutely nothing to do with the fact that we used glucose here as opposed to maltodextrin as the basis vector. The linearity of our sound encoding has absolutely nothing to do with the fact that we assigned x's encoding to 10kHz as opposed to 12kHz.
So what pray tell are you even talking about?
Quoting A Raybould
I'm more than willing to grant that variability on experience (among people) needs study; the point of going over these examples and objections isn't to present an opinion, but rather to present reasons not to form a particular opposing one until we get more information.
But I don't think your objections about the linearity of a vector space depending on what the basis vector represents are even coherent. It appears to me that you're trying to support a conclusion that if everyone agrees this is orange, their solutions representing the color must all use glucose, because we would have to make an assumption that maltodextrin solutions can also represent consensus of orange before concluding that it could possibly be maltodextrin. That is the very kind of thing I'm arguing against... garbage arguments for an opinion (in this case same-experience), which push comes to shove are double standards of burden of proof (too low justification required to conclude same-experience but more than what should reasonable required to reject it). You should not in this case claim that you have adequately justified same-experience until you have measured the glucose in the solutions of various people.
Ha! this is just a long-winded way of attempting to hide that you are failing to refute what I have been saying: people generally agreeing on categories implies a degree of commonality in the mapping of sensory input to experience. We also have examples of second-order variance from this commonality, as demonstrated by various forms of color-blindness, which need not necessarily arise at L1.
At this point you are reduced to attempting to pin straw-man opinions on me, with some motte-and-baileying thrown in.
By the way, you may have missed some additional points that I added to my previous post after first submitting it.
There's a difference between a mapping being equivalent and the thing being mapped to being the same. This is how you originally engaged me:
Quoting A RaybouldQuoting A Raybould
I read "in detail" and "fundamentally differently" as describing that what's being mapped to being more or less the same. Additionally, you posted the first thing in response to this quote:
Quoting InPitzotl
So I'm not quite sure "straw man" is the right term for it... it's pretty easy from this reading to get the interpretation that you're claiming that if the mapping is the same then the things being mapped to should be the same. But let's just clear that up right now.
Are you arguing that if the functional mappings are equivalent (say, in the sense that if the behaviors of ranking things into categories are the same), that this implies that the experiences are the same?
ETA:
Quoting A Raybould
I have no idea what you mean by "not necessarily" (are you envisioning some universe where established science is wrong?), but it's already established that protanopia/protanomalies are associated with L cones, deuteranopia/deuteranomalies are associated with M cones, and tritanopia/tritanomalies are associated with S cones. We know that the former two are common in men due to the fact that the genes for L and M cones are on the X chromosome and absent on the Y chromosome, so females get an extra copy of them (note that S cone encoding is not on this chromosome). For similar reasons it's females who tend to be tetrachromats because the rarer OPN1MW2 gene could be present on one of these X chromosomes, and OPN1MW1 on the other, presenting as two different encodings of "the M" chromosome. These genotypes encode for differences on the opsins, and differences of the opsin proteins modulate the sensitivities to particular frequencies of light that these proteins react to when they photoisomerize (fold based on absorbing a protein), which is the primary biophysical mechanics triggering color vision. (Note: There are also L cone alleles). The effect is that these two variants of M chromosomes in effect become two distinct photoreceptors. So according to these established modes of color blindness (and tetrachromacy), they are in fact at the L1 level.
Quoting A Raybould
It's almost a direct translation. L2 colors are our experiences. An inverted spectrum philosophically is by definition an inversion of the experience of colors, ergo, it would be an inversion of the L1 color space mapping to the L2 colors.
Quoting A Raybould
If there's an inverted spectrum, the mappings from L1 to L2 colors would be inverted, but the continuity of said mappings need not be affected. The only behavioral argument on the table so far is: "evolution is very conservative about things that are important to fitness, and our minds". That reasoning presumes there's a fitness advantage, but you would need to explain an actual advantage to make this argument solid (again, we don't all have green eyes by this argument).
Quoting InPitzotl
And in quoting me, you left off the very next line:
Quoting A Raybould
Later on, I wrote:
Quoting A Raybould
so it is not as if I am imputing straw-man arguments to you.
Quoting InPitzotl
The only invocations of inverted qualia that I am aware of are in modal metaphysical arguments against functionalism. I may be mistaken, but I do not think that even a majority of the philosophers who invoke these arguments have much commitment to the proposition that such cases occur in the actual world, and the philosophers who do seem to be a minority of all philosophers.
More generally - and I think it covers all the points you have raised here - you are saying that there are cases where disparate experiences would have no observable behavioral effects, and I am saying that nevertheless, there are other cases in which they would (plus that I am of the opinion that commonality of experience, at a functional level and as a first-order effect, is a plausible hypothesis, for reasons that I will get into below.) Inverted spectrum scenarios are not the only way in which two people might differ in their experiences, and not all of those alternatives would result in them agreeing over the categorization of colored objects.If you can invoke inverted spectra, surely I can invoke these others!
Of course, if you summarily rule out all scenarios, in which the two parties would not agree on color categories, as "incoherent gibberish", then of course they could differ over the full range of remaining possibilities and never disagree on the categorization of color!
Quoting InPitzotl
This is an issue you raised, not me: Quoting InPitzotl
And I replied with the response that I have not yet seen any reason to change, "not necessarily." I'm not making a point here, I am merely answering your question. I assumed your question was the prelude to an argument on your part, but I do not believe we have seen the follow-on yet. And if you object to "not necessarily", are you not arguing for "necessarily?" What else is there?
As to what my position is:
It is my impression that the idea, that we cannot and could not tell if our experiences are the same, is the majority view, and it is one I used to hold, but I have come to think of it more likely than not that they are, up to the level of first-order effects. My reasons for suspecting this to be so are these:
Empirically, neurophysical studies using multiple subjects work - they produce quite specific results that can reasonably be taken as general, applying to the majority of the population. In study after study, some aspect of mental functionality is found to be expressed in the same small region of all the subjects' brains, so the evidence is that our brains are quite similar up to an architectural level, and at least to some functional level.
It would be a fair point to say that these studies have only gone so far in figuring out how brains work, though this strikes me as being like a 'God in the gaps' argument. It is at least plausible that this commonality will continue to hold as we advance our understanding of how brains make minds.
A dualist might say that it is possible for two people to be identical in every possible physical way, and still have different experiences (that's what inverted spectra arguments claim), but I am not a dualist and I doubt this is possible; I reckon that if we could acheive a complete, causal, physical model of the brain, we would find that's all there is, and that there isn't anything beyond that for experiences to differ over.
You have attempted to dismiss this as my attempt to impute attitudes to researchers, but it is actually based on the empirical fact that these multiple-subject studies work, and that it is uncontroversial to generalize the results from the studies' subjects to the general population.
Secondly, the human brain is a network of neurons trained over hundreds of millions of years, and at each generation, the information accumulated by that training is squeezed into DNA and reconstituted. It is certainly possible that, while externally our minds function similarly in many ways, under the hood, each brain is working quite differently than any other. A more parsimonious expectation, however, is that this multi-generational training has produced brains that function alike, to a first approximation. If they did not, how likely is it that they would have, so to speak, 'learned the lessons' imparted by evolution? If a child's high-level brain function can vary markedly from that of its parents, how likely is it that it would nevertheless still be behaviourally similar enough that the child has approximately the same level of that part of its fitness that comes from its mental abilities? Alternatively, what sort of mechanism would be needed to conserve the external behaviour in the face of internal variation? We cannot depend on evolution doing that, as evolution is itself dependent on the conservation of fitness traits from parent to offspring.
As for your objection that we don't all have green eyes, here is where the point about evolutionary conservatism (selection results in tight constraints on variation in matters that are strong determinants of fitness) comes in: we can have various colors of our irises because the particular hue of their pigment does not strongly determine fitness and so is not strongly selected for. I do not think it is very speculative to say that our mental abilities are strong determinants of fitness (unless, of course, one thinks our experiences are epiphenomenal.)
To be fair, I have not made these arguments in this detail before, though they have all appeared in abbreviated form. One advantage of this discussion is that I have given the issue more thought.
So this is all speculative, but I wrote this earlier, and you said at the time that you accepted it:
Quoting A Raybould
Furthermore, what are the counter-arguments, other than that it is speculative, which isn't a fatal flaw in a mere hypothesis? You appear to have started into an argument based on us agreeing on color categories, but you do not appear to have finished it yet. Earlier, you wrote:
Quoting InPitzotl
OK, like my views, it is an opinion, but to me this looks like 'guilt by association': it seems, to you, like other arguments, ones that suffer from "hasty generalization" and "personal incredulity" - but how are these flaws manifest in this particular argument? What do you think I am being incredulous of?
See section 3: https://plato.stanford.edu/entries/qualia-inverted/
I'm not so concerned with consensus among philosophers or any group of people for that matter... a million guesses is still not evidence.
Quoting A Raybould
I agree on that part, but I think you're confused. You specifically asked me for arguments to support that our color experiences were fundamentally different... I provided them.
Quoting A Raybould
Great! This is certain to be a more useful analysis. But going in, I disagree that the premise "we cannot and could not tell if our experiences are the same" is justified.
Quoting A Raybould
...okay, so I'll call this the architectural argument.
Quoting A Raybould
It's true that we share general architectures; this is the foundation for being able to describe such things as the visual cortex, areas V1 and V4, the ventral and the dorsal stream, and such. But it's still a bit of a mystery how colors are encoded; so far, color analysis seems to be a bit distributed. So yes, we can't quite claim that we've figured out how the brain works. But, yes, this is the most promising area of study, and this is the type of thing to appeal to in such arguments, but there's a bit more work to do. You still can't quite say though the architectures are the same therefore the experiences should be. You have to call apples apples and oranges oranges. You should talk about the candidates for the experiential correlates being the same. Just because our brain shares an architecture doesn't mean it'll share everything.
Quoting A Raybould
Sure, but I'm not sure dualists can claim adequate justification.
Quoting A Raybould
Not exactly... I've pointed out a situation where you're basically guessing researchers share your view and then appealing to the researchers having your view, which is basically an appeal to authority as a fallacy.
Quoting A Raybould
The description here in terms of evolution sounds a bit Lamarckian. Also, this is quite hand wavy. There's "information" that we share based on evolution. From there, you go to specifying that particular kinds of "information" must be shared, because the alternate theory is that "information" is not shared.
Quoting A Raybould
Too vague and hand wavy still. Evolution isn't a teacher teaching individuals lessons. It's just a blind process that happens to do what it does. Natural selection tends to keep the genes around that tend to stay around; sexual reproduction tends to shuffle genes around; genetic mutations of specific types tend to just happen at particular rates. Brains don't just behave... they learn; ANN's aren't quite the same thing as a brain, but they're success stories (to the degree that they are) in mimicking how brains learn at some level. Behaviors important to survival are significant, but brains come with hormone systems, body sensations, drives, and instincts for such things. Also, it sounds pretty expensive to code entire brains into a genome, in terms of genomic cost, and evolution is known for being "good enough" (it's why we tend to die of old age... we simply don't need to live that long to pass our genes into the gene pool so the selection pressure dips below what's needed to keep up with mutation rates).
We're not talking about high level brain functions here. We're talking about the experiential correlate of a color.Quoting A Raybould
Any isomorphic mechanism would do the trick. Instead of using high and low circuits for 1's and 0's, we could use magnets being in the same or different directions. It doesn't really matter, so long as a change is a change. Instead of encoding y as glucose in the solution we could encode it as maltodextrin.
Quoting A Raybould
Evolution is only selecting for fitness where it matters. If a variation does not affect fitness where it matters, evolution would not care about that variation. You're in effect just begging the question; you're assuming that the variations would have an effect on fitness and then arguing that evolution would select those out:Quoting A Raybould
So green versus blue eyes don't seem to matter much to fitness.
Quoting A Raybould
In what way?
Quoting A Raybould
...not quite, but the disagreements are in the weeds (e.g. it's possible to formulate a theory before a hypothesis)... and not quite useful for this discussion.
Quoting A Raybould
Counter-arguments fall back to debate mentality. What we're really interested in is the truth. So the analysis to be done on a hypothesis is to explore the ways in which the hypothesis could reasonably fail. That's what I've been doing here.
Quoting A Raybould
It's very simple. The burden aligns with the purpose. Let me start with a summary of what I see you as doing and get back to this.
You are advancing an argument that evolution theory suggests same-experience... the burden on that is fairly high, and has not been met. To adequately justify this, you need to show how evolution is inconsistent with different-experience. The first argument you advanced failed very quickly with a sanity check; green-eyed people not being universal suggests that evolution doesn't always produce universal traits. What was really missing from this argument was relevancy. You did a little better with the second argument but you're still missing the relevancy... you seem to beg the question by thinking backwards about it, something along the lines of "if different-experiences were had, there would be differences in fitness". I claim this is backwards because you're trying to start at evolutionary fitness and then conclude same-experience, so the real challenge here isn't fitness-affecting differences, it is fitness-invariant differences.
That's where the arguments I'm providing come into play. The purpose of these arguments is different, and along with this comes a difference in burden. There is no argument on the table that evolution supports the different-experience theory, so there's no need to demonstrate that it does. The argument rather is that evolution is compatible with different-experience theory. If it's simply compatible, then we can reach the intended conclusion, which is not that we have different experiences... but, rather, that you have yet to adequately justify that we have same-experiences. Now were the argument on the table that we actually have different-experiences of color, the burden would shoot up matching the burden I'm expecting of you. But the actual stated position I'm taking is a non-position.
Sorry, I am not clear on exactly what issue it is that you want me to address. The paragraph preceding the one from which the above quotation is extracted makes it look like the point you want to make is that if current science is incomplete, then there should be no philosophical arguments brought forward to eliminate a given avenue for its advancement. Is that the issue you want me to address? Or is it that there should be no such philosophical arguments brought forward which contain as a premise that current science is incomplete?
That there is a distinction between, on the one hand, being in a physical state P, and, on the other, knowing all the facts associated with being in a physical state P, does not seem to be a distinction over looked either by Jackson or by me. The issue concerns in what that distinction consists. I can know all the facts about the physiology of sitting in a chair. What knowledge or other epistemic quality do I gain by being in that state for the first time that I did not already have before being in it? Here the reply "nothing" seems to have as much going for it as "something". The intuition on which Jackson's argument and mine rely is that "something" has a stronger pull when the example in question concerns seeing something red for the first time. As I have already admitted, it is just an intuition. However, if you accept the intuition, then something substantive should be said about what it is that is gained, and that is not a burden that falls on the materialist alone. The dualist also has to give us something to work with. For what it is worth, I do not believe either side has a particularly coherent idea about what it is that is gained that would pin it down sufficiently to provide grounds for further investigation.
I think we should reset this discussion, and start over.
Firstly, let's get rid of the ambiguous phrase "physical knowledge", and replace it with "knowledge of physics", and similarly, replace "physical fact" with "fact about physics", "physical proposition" with "proposition about physics", etc. If we reach a point where this substitution does not express what we want to say, we will find an alternative, non-ambiguous substitution. In particular, if "physical information" comes up, we will use either "information about physics" or "information coded in physical form", according to which we mean.
Secondly, let's put aside what the skeptic believes. If you like, imagine the skeptic is someone who leans towards dualism but still doubts that your argument succeeds.
Thirdly, let's use Churchland's 'equivocation' objection as modified by Torin Alter and Tim Crane, which uses the concept of discursively-learnable knowledge. This simply means any knowledge that can be gained through reading, or by attending lectures, seminars, tutorials, etc., or watching or listening remotely - i.e., any knowledge that can be conveyed language backed up by illustrations and demonstrations (though not, of course, in this case, any visual that needs to be in color!). This looks very much like propositional or factual knowledge, but by tightening the argument by using 'discursively-learnable' instead, we can simply avoid getting mired in the question of whether the intellectualists are right in claiming that all knowledge is propositional: even if they were right in some sense, Churchland's rephrased objection is unaffected, as it does not rely on making any distinction between propositional and non-propositional knowledge.
In your definition (and Jackson's), all knowledge of physics is clearly discursively-learnable (even when one deduces a fact from others, the line of reasoning that led to the deduction could be written down and learned by others from those words, so it, too, would be discursively-learnable.)
What (if anything) Mary learns from seeing colors is either discursively-learnable or it is not. We can consider these two cases separately.
If it is not discursively-learnable, then physicalism is not challenged by Mary not learning it until she was released, as she could have learned all the discusively-learnable knowledge that could ever possibly be known, and still learn something more. It is irrelevant whether what she knows before being released is knowledge of physics or of something else.
Alternatively, if her new knowledge was discursively-learnable, then why could she not learn it from her studies? You cannot simply assert, without justifying the claim, that it was not knowledge of physics, and therefore ruled out by the premise, as that would be begging the question.
Whatever else you say about your argument, you must also address this issue if you want to claim that it avoids Churchland's charge of equivocation. Therefore, I urge you to confine your reply to anything that is germane to this particular issue, so that we do not get mired in side-issues.
Quoting InPitzotl
The SEP is an excellent resource, and in section 2 we have a discussion showing that it is not straightforward to find an inverted spectrum scenario that is clearly behaviorally-invariant (and as we will see, my argument is not defeated by the existence of some scenarios that are.)
"Too vague" seems to have become your default response, but by itself, it is too... vague? Are there any non-vague metrics of vagueness, and more-or-less objective thresholds? The falsifiability criterion of science provides one (despite not being directed specifically at vagueness alone), and it is an appropriate one here: Vague claims (such as of vagueness exceeding some unspecified threshold) are not falsifiable.
What I am saying here could be falsified; a (not-yet-achieved) causal model of how the human brain produces a mind would reveal whether, to a first-order approximation, most humans are undergoing the same physical functions when they experience color. That's good enough for a hypothesis.
For physicalists, where there is no physical difference, there is no difference simpliciter. As I mentioned previously, dualists disagree, but so long as dualism is speculative, it is not enough to rule out my hypothesis: at most, I can restrict it by adding the premise of physicalism, which, despite all efforts, has not been ruled out. And while this is a side-issue, there is nothing more vague than dualists' concepts of the non-physical; there are no hypotheses about how the allegedly non-physical or extra-physical aspects of minds work. As someone who rejects all real and imagined vagueness, you presumably have no truck with dualism.
There are a number of misunderstandings in your post:
Quoting InPitzotl
More specifically, I asked was what objection you had to my reply "not necessarily" to your question "If I experience red a different way than you experience red, wouldn't we still both call red things red?", and your replies only demonstrate possibility where, to be a reply that addresses the evolutionary question, arguments for necessity (or at least predominance) are necessary As far as I can tell, you never did finish the claim you had launched into with that original question.
Quoting InPitzotl
...And it is a claim that you have already been corrected on, and, moreover, right in the part of the quoted sentence you cut out. The full quote is this:
Quoting A Raybould
- no appeal to authority there.
Quoting InPitzotl
That puzzled me, but I see that I was not being clear here. I am not saying that a child inherits from its parents' adult minds, complete with what they have learned (that obviously does not happen.) I am only using a completely conventional concept of evolution, and it might help if I go through them one by one:
Quoting InPitzotl
That might seem to be so, to someone unaware of what I wrote about it immediately afterwards. Once more we see the pattern of quoting out of context.
As for the paragraph you followed this with, it is all addressed in the above list, which is just a selection of the relevant positions taken in conventional evolutionary theory, with regard to the evolution of any organ, not just the brain. If you like, I could go through how it does so sentence-by-sentence, but I think it would be unnecessary clutter to belabor each point in turn.
Quoting InPitzotl
And what are those correlates?
Quoting InPitzotl
I think you are missing the point here. As we have seen, it is not the case that no matter how a child's "experiential correlates" of sensory input differ from those of her parents, it could not have any behavioral consequences. Given the empirical evidence that children and their parents do, to a first approximation, behave similarly with respect to their sensory stimulation (generally agreeing on the categorization of colors, for example (your example, as it happens)), then it seems that, whatever internal correlates they have to those stimuli, they are generally from the subset of possibilities that preserve this commonality of behavioral responses. The question then is, if childrens' internal correlates of stimuli are free to differ markedly from those of their parents, what genetic and ontological mechanism might there be to restrict the variation in the experiential correlates such that the behavioral commonality is preserved?
Quoting InPitzotl
Not at all - you are arguing against your misunderstanding of my argument. My point is based on empirical fact: if variation is routinely producing children that have markedly different functional responses to color stimuli than their parents, then how come we only very rarely see those variations that do not result in observable differences?
Quoting InPitzotl
So we agree on something. Is it too much to think that we also agree that this lack of fitness is because the primary function of the iris' pigment is to block the transmission of light, and so what it reflects is not consequential?
Quoting InPitzotl
The alternative is so lacking in plausibility that I will not bother to reply until specific arguments for it are presented. Extraordinary claims require extraordinary evidence.
Quoting InPitzotl
(By the way, I'm curious about what was, at some point, a theory but not a hypothesis.)
For reference, let's see what you are still not disagreeing with in any material way: "In scientific inquiry, theories are preceded by hypotheses. You don't have to believe them, just consider them. Of course, if there is contrary evidence rendering a hypothesis unviable, then it is summarily rejected and science moves on, but that does not seem to be the case here." I will have more to say on that below.
Quoting InPitzotl
Argument and counter-argument are the principal methods of philosophy, and are important in science; these are both generally regarded as attempts to discern the truth. What is not acceptable are various ploys often seen in other arenas of debate, such as the repeating of a claim after it has been refuted, as if it had not been, or quoting out of context.
Quoting InPitzotl
To the extent you have been on-point in that respect you have been helpful, and I thank you for that - but your work here is not complete.
Quoting InPitzotl
The last time you said that, you shortly afterwards backed away from the claims that followed... What you wrote here did not actually throw any light on what I am being incredulous of, which is fine if you are no longer making this claim.
Quoting InPitzotl
As you have misunderstood the evolutionary argument, your judgement of its efficacy is suspect.
Quoting InPitzotl
As we have seen above, you did not follow that argument, and, as a consequence, replied with a non-sequitur.
Quoting InPitzotl
As we have seen above, you did not follow my arguments, and, as a consequence, you are arguing against your own mistaken attempt to paraphrase my position. Furthermore, any scenario, in which the different-experience hypothesis has a difficulty explaining observations and the same-experience hypothesis does not, is an argument (or evidence, if it is an empirical fact) for the latter over the former.
Quoting InPitzotl
I don't recall that argument being made - could you point me to where it was?
Quoting InPitzotl
While your stated position, being indefeasible (though trivially so) is a strong one to sustain during a debate, its usefulness in the search for knowledge is wholly dependent on other people looking for answers.
As soon as a thesis is mooted, both it and its antithesis exist as hypotheses, regardless of your personal attitude to them. While your stated goal, apparently, is to show that the notion that our experiences are similar to a first approximation does not achieve hypothesis-hood, the closest option you have to that is to summarily dismiss it. There are several ways you could achieve that: You could show it to be incoherent or internally inconsistent, or you could show it to be ruled out by established facts. You could show that it is unfalsifiable. Failing any of these, you could, if you had an alternative view, argue that it is so much more plausible, than the alternative, then the latter is barely worth considering - but, absent that differential plausibility, implausible hypotheses cannot so easily be dismissed (plenty of previously implausible ideas have become theories.) By simply presenting ways in which new knowledge could defeat it, you are already treating it as a hypothesis, and will continue to do so up until the point where you achieve one of the above.
BTW, in reply to an earlier ETA:Quoting InPitzotl
I am guessing that your emphasis on 'established' indicates that you were aware of this, but I had in mind cerebral and congenital achromatopsia and dyschromatopsia, color agnosia, and any related pathologies.
You're confusing your opinion with your argument. The stuff in section 2 is a different argument than what you've presented. Regarding that, some of the arguments in that section are in fact decent and relevant, but they do also presume things about color processing for which we really need more detail. For example, take this from SEP:
Quoting Inverted qualia
...which does seem compelling (more generally, qualitative "inter-qualia" comparisons yield subjective asymmetries like this), but there are potential L1 reasons for this (via color opponency):
Red/green and blue/yellow are opponent color processes involving respectively some L-M and L+M-S function, with brightness being roughly an L+M+S function so close to just M that it's modeled that way in some color spaces. So for real colors, variance from green to yellow has L-M going from balanced to low without changing L+M-S balance much, whereas variance from red to blue has the same L-M variance going from high to balanced while also the L+M-S process goes from high to low. So in this case, the variation of real colors from yellow to green is expressed in the variation of just one color channel going from neutral to green, but the variation of real colors from red to blue is expressed in the variation of two color channels transitioning inversely from yellow+red to blue+neutral. Similarly with yellow versus brown being quite different versus blue and dark blue, yellow has an incredibly high brightness whereas blue starts out at fairly low brightness (relative luminance). Since these are L1 like properties, inverting the mappings from L1 to L2 colors may still carry these properties; IOW, an inverted spectrum might not quite be as much like flipping an RGB image's colors as one might presume.
Quoting A Raybould
It's not exactly a default response so much as it is prompted:
Quoting A Raybould
...in relation to the topic at hand, this is indeed too vague. Your expectation is more parsimonious than what exactly? Function alike in what ways? What "learned lessons"? I'm perfectly happy to say that human brains evolved in human like ways, but that does not really imply same-experience unless you can connect the similarity of human evolution to the similarity of color experience, which I've yet to see. Other than that, it's yet another nature versus nurture debate. Truth is, both nature and nurture make brains, especially human brains.
Quoting A Raybould
Because, for example, predators aren't examining your brain with fMRI to see if you represent redness on this spot or that spot or using this average frequency of pulses or that frequency? The important thing from a fitness perspective is that you run away, hide, or fight the predator appropriately.
Quoting A Raybould
That's your choice, but in effect, given that you're the one claiming to be supporting a proposal that the experiential correlates have a fitness advantage, not answering the question absolutely equates to not addressing the very thing your proposal is supposed to be about. If your proposal is about a tie between fitness and particular experiential correlates of color, it is backed if and only if you can demonstrate what it is about... i.e., tie fitness to experiential correlates of color. This is what I mean by relevance.
Quoting A Raybould
Sure. So let's focus on the correlates, since that's where the difference would be.
Quoting A Raybould
I don't know, but I think that's the key question. In terms of L1 colors, there are reasonable explanations of development that are works in progress but involve self organization; these generally produce opponent color processes. Example:
https://www.frontiersin.org/articles/10.3389/fncir.2014.00016/full
This itself requires a bit more study. In terms of color perception in the brain, as I said before, we know there are multiple places of analysis. But there's also the possibility of potential signal space (such as these toy models of potential Poisson rates)... and since the signals potentially start this way there may be transference from these signal rates to positions, or not. But "qualia" may be more complex than many philosophers tend to treat it as well; e.g., there's such a thing as pain that doesn't hurt, suggesting that qualia aren't necessarily singular in the first place. This might be explained as pain in practice actually having separable pieces that typically are co-associated but not essentially so, and the same could possibly be true of color. What we're looking at developmentally for different-experience would be any sort of theory that starts with this brain in a semi-random developmental state and just "settles into" the "nearest corners". The entire question here (that has not yet actually been addressed) is how many "corners" are there, why are there that many, and how do the L1 colors map into them? Assuming opponency-sized "corners", a same-experience theory would postulate four to six of them, and some sort of specific developmental pathway whereby particular opponent signals latch into the specific four (or six) that they're supposed to map to.
Quoting A Raybould
...I'm fine with that, but "adequately justified" is more akin to what you're saying being verified.
Quoting A Raybould
Yes, but counterarguments should not have to require an opposition taking a side to provide the counterarguments, and most certainly should not require the opposition to hold the countering view as an opinion. Also, two people discussing a thing need not necessarily each pick a corner and box; it's entirely possible, and may even be more productive, for the two to simply walk hand in hand from corner to corner.
Quoting A Raybould
So, let's get back to tetrachromacy. Let's suppose we introduce a new gene in the human gene pool, call it OPN1MW3. OPN1MW3 expresses in people who have it by producing an M cone with spectral sensitivity shifted towards blue by the same amount (measured in frequency) that M shifts L spectral sensitivity towards blue; let's call this a N cone. This gene is an allele for the M on the X chromosome. So suppose we have: (a) Adam, who has L, M, and S cones; (b) Bill, who has L, N, and S cones; (c) Cindy, who has L, M, N, and S cones. So here are some questions. (a1) Is Adam likely to be a trichromat? (b1) Is Bill? (c1) Is Cindy more likely to be a tetrachromat or a trichromat?
(c1) is the interesting question... but regardless of its answer we still have followups. If the developmental process is such that Cindy's likely to become a tetrachromat, then there are questions about what exactly causes the L2 colors that Bill sees; your hypothesis suggests it's some built-in gene, but if self organization suffices to establish L2 colors this is questionable. But if Cindy is only a tetrachromat if she has some other specific gene, some BN (brain-gene-N analog; here, this is just a generic referent... it could be more than one gene), that pre-structures her brain, then we must also ask whether Bill can have that gene as well, or under what conditions precisely Bill sees what Cindy sees that Adam doesn't see.
Your hypothesis seems to require a "BM" gene of sorts. Okay, we have the human genome mapped out... so which gene is BM?
Quoting A Raybould
The point isn't to simply maintain some position with unreasonable standards though. The point is to require relevance. The thing being talked about here is the actual stuff happening between our ears in our soft pink squishy warm brains, that has to do with our subjective conscious experience of colors. Some discussion of and/or constraints on how that subjective experience's correlates develop is necessary to provide a theory of how much the subjective experience's correlates can vary. Without having that discussion or addressing what those constraints are, you're just plain not having the required conversation.
Quoting A Raybould
I've no objection to same-experience as a hypothesis. My objection is claiming that the hypothesis is adequately justified prematurely.
Quoting A Raybould
Achromatopsia and dyschromatopsia are the same modes of L1 level color deficiencies previously discussed (though there are acquired forms). Color agnosia as far as I'm aware is a defect of the ventral stream, which is particularly interesting for awareness of L2 colors at all (if not L2 modes of color at all). I would be interested in an L2 specific defect.
OK, so this argument puts off the question of accepting whether or not Mary learns anything.
I guess against this argument, the skeptic would have to push the investigation of the supposed distinction between knowledge being discursively learnable and knowledge being physically encodeable. What does "physically encodeable" mean? Given the representationalist background of most versions of physicalism these days, I suppose one proposal for a gloss of "physically encodeable knowledge" would be knowledge the content of which is entirely representational in or through a physical form. So, a premise of the Churchland/Crane/whoever argument is that there is a distinction between knowledge that is discursively learnable and knowledge, the content of which is entirely encodeable in a physical medium. So what is content? Content is propositional. Even if one accepts the idea of non conceptual content, that is not to accept the idea that there is content that cannot be expressed in terms of propositions, it is just to accept that the person having the mental state with that content need not have the resources to state those propositions. So if all content is propositional, then not only is all discursively learnable knowledge physically encodeable, all physically encodeable knowledge is expressable as propositions and so is discursively learnable. Thus, perhaps, one way in which the skeptic might try to deal with the Crane/Churchland/whoever argument by collapsing the distinction required by one of its premises.
1 If some item of knowledge is physically encodeable, then it is discursively learnable
2 The item of knowledge Mary gains is not discursively learnable
_________________________
The item of knowledge Mary gains is not physically encodeable
The support for premise 1 would of course have to be independent of any issues concerning Mary, and I gave an indication of one way that might be done in the previous post.
Quoting jkg20
I am puzzled by this. The claim that Mary learns something from seeing colors is a premise of Jackson's argument, and yours too, if I am not mistaken. We only reach the two cases here if that premise holds up; if it does not, the argument has already failed.
Quoting jkg20
It is not clear (at least, to me) to which argument you are referring, or what 'push the investigation' means. The meaning of 'discursively learnable' and 'physically encodable' seem to be straightforward, at least within the context of Jackson's argument:
Discursively-learnable: Knowledge that can be learned by discourse, which is to say linguistic communication [1].
Physically-encodable: Claude Shannon developed the canonical theory of information, in which information is present whenever things are arranged one way when they might be another, and any specific piece of information is encoded in such differences. Physically-encoded information is information that is actually encoded in physical states that might be otherwise - a coin that is heads-up when it might be tails-up, for example - and physically-encodable information is that which could be so encoded. I suppose that any information can be physically-encodable, precisely because the medium of encoding is immaterial (pun intended) to the information content.
Quoting jkg20
To be clear, the distinction is not one of mutual exclusion; in fact, if all information is physically-encodable, as I suggested above, then discursively-learnable knowledge is a subset of knowledge having physically-encodable information content. The distinction is that they are two different aspects of knowledge.
It seems odd to call this distinction a premise of the argument, as it is just a matter of defining two terms, and it is simply a fact that they have different definitions; furthermore, denying it would not seem to help Jackson's case.
Quoting jkg20
This is a very big assertion, and the justification you offer here does not even begin to do the job. It is not just a possibility, but a fact, that some people have a pathology that prevents them from stating something they know; nevertheless, you cannot deduce that content is propositional from that - it is simply an invalid argument, one for possibility where one for necessity is necessary. As we shall see, it is also moot in this case.
Quoting jkg20
The italicised conclusion does not follow, even if the conditional here were to be true, as, to be discursively-learnable, knowledge must be communicable. For one thing, note that, in what you said to justify saying that all content is propositional, you made the case that people might have propositional knowledge that they cannot state, which would seem to be an insurmountable impediment to it being communicated!
Furthermore, if this argument were valid, then it would apply to all knowledge, not just all physically-encodable knowledge (if there is a difference), and so all knowledge would be discursively-learnable, which is the other horn of the dilemma: In that case, what would have prevented Mary from learning it prior to her release?
Quoting jkg20
It is not clear to me that anyone has to defend this argument, but, as we have seen above, your current argument for premise 1 does not succeed, even on its own terms.
[1] On writing this, it occurred to me that it might be disputed whether anything Mary deduces is discursively-learnable. I think it is, because the deduction process itself could be expressed in words and communicated. The issue is moot as far as Jackson's argument is concerned, however, as completed physics already includes everything that can be deduced from other facts - in fact, Jackson stresses this point in his papers, as his argument depends on it.
You are mistaken. My argument that you are referring to contained the conditional premise that if one accepts that Mary gains knowledge, then there is an obligation to say something substantive about what she gains. Jackson's argument states that Mary gains knowledge. But your misunderstanding on that point is a peripheral issue anyway, since we have now moved on to a different, and more fundamental, disagreement. Let's try a new argument:
1: All information content that is encodeable is expressable as a finite set of propositions.
2: Any finite set of propositions is discursively learnable.
3: From 1 and 2; all information content that is encodeable is discursively learnable.
4: Anything that is physically encodeable is information content that is encodeable.
5: From 3 and 4 anything that is physically encodeable is discursively learnable.
6: At time t, Mary knows everything that is discursively learnable.
7: Mary gains new knowledge when at t1 she sees a red thing for the first time.
8: From 5, if what Mary learns at t1 is physically encodeable, then it is discursiveley learnable.
9: From 8 and 7, if what Mary learns at t1 is discurvively learnable, then she did not know at t everything that is discursively learnable.
10: From 8 and 9, if what Mary learns at t1 is physically encodeable, then Mary did not know at t everything that is discursively learnable.
12: Since the consequent of 10 contradicts 6, by modus tollens what Mary learns is not physically encodeable.
The premises here are 1, 2, 4, 6 and 7.
Nothing you have said would lead me to think you would reject 2.
Your remarks about the notion of physical encodeability suggest to me you would also accept 4.
I'm not sure whether you accept 7 or not. You have not stated explicitly that you do, although many of your remarks seem geared up to defend physicalism even if 7 were true. Nevertheless, without explicitly accepting it, I am not going to force it upon you. As I have said a few times, the motivation for it is just an intuition pump.
I am also not clear whether you allow the possibility of premise 6 being true or not. It may be incoherent, although I do not see any obvious contradiction.
So, this leaves 1. Why accept 1? Well it is totally in accord with the information theory that Shannon developed. True, Shannon's original paper talks about the transmission of messages rather than content, but it is not a stretch to identify the term "information content" as used in the argument above with "message" as used by Shannon, and a message is very definitely something expressable in a finite set of propositions. Having said that, Shannon takes the notion of a message pretty much for granted.
Are there counterexamples to 1? Note that it is not a counterexample to point out that there might be people with contentful states that are pathologically unable to express that content. That some content cannot actually be expressed by a some specific individual in a set of propositions does not entail that the content is not expressible by such a set. In fact, if you tried to come up with a detailed counterexample of this type, it would probably be self stultifying, since you would have to identify, through propositions, what the content of the state was that the person was unable to express.
Might there be unecodeable information? Sounds like that might be a contradiction in terms, and in any case, it is not really a line a physicalist would want to push. Might there be information content not encodeable in a finite set of propositions? Well, transfinite information theory does not exist as far as I am aware, but that may be ignorance on my part.
Quoting jkg20
You say I am mistaken in saying that it is a premise of yours that Mary learns something from seeing colors, but your premise 7 is that "Mary gains new knowledge when at t1 she sees a red thing for the first time." Do you make a distinction between "learns something" and "gains new knowledge"? If so, what is it? Alternatively (or additionally), do you suppose that her new knowledge is not a consequence of seeing red - that these two events are just coincidental? I do not suppose you do, as this latter supposition would invalidate the argument, but I am at a loss for why you think I was mistaken.
Also, note that "new knowledge" is ambiguous here. It is new to Mary, but as Jackson goes to some length to point out, it is not new as in having just become true at t1, as, for his argument to succeed, it must have been a fact that Mary could have learned prior to t1, and one cannot learn non-true facts, as there are no such things. This is the point behind Jackson's insistence that what she learns is a fact that was already true about other people.
As for what you thought I was referring to, your "conditional premise that if one accepts that Mary gains knowledge, then there is an obligation to say something substantive about what she gains": I have said something substantive: either it is discursively-learnable, or it is not. As Jackson's argument fails in either case, a skeptic is under no logical obligation to choose one over the other.
If you think this is insufficient to meet the obligation, then it should be possible for you to show that there is a logical obligation to say more, by showing that the counter-argument is invalid without it. This you have not done.
Now, to your latest argument. There are quite a few claims that I could quibble over, but I will focus on the ones that are decisive.
1: All information content that is encodeable is expressable as a finite set of propositions.
To avoid equivocation later on, we have to be careful here over what it is about the information that is expressible as propositions (especially given the distinction you made between 'expressible' and 'can be stated' in your previous post.) The physical state encoding any specific case of physically-encoded information can be described (in the language of completed physics) but, to be clear, the description is not the state (the map is not the territory), and even though the description may itself be physically-encoded, the physical state in which that description is encoded is not the physical state which is described by that description - for example, the physical state being described can change without the physical state encoding the description changing. Therefore, I do not accept this premise, though I will accept this:
1': The physical states encoding all physically-encoded information can be described in a set of propositions.
2: Any finite set of propositions is discursively learnable.
I will accept that; as this is a thought experiment, we can put aside the objection that Mary's ability to simply remember propositions is limited.
3: From 1 and 2; all information content that is encodeable is discursively learnable.
Once we substitute 1' for 1, it is clear that this does not follow; the most that one can deduce from 1' and 2 is this:
3': Any description (in the language of physics), of any physically-encoded information content (of someone's knowledge), is discursively-learnable.
4: Anything that is physically encodeable is information content that is encodeable.
I cannot accept this, either, as only a small amount of all physically-encodable information is the information content of knowledge. For example, the angular momentum of some undiscovered exoplanet encodes some sort of information, but it is not the information content of anyone's knowledge. For a bit of physically-encoded information to be part of the information content of someone's knowledge, it must be encoded by a physical state within that person's brain. If Mary could have knowledge which had its information content encoded in someone else's brain, she would have telepathy, and there would be no justification for the belief that, before seeing colors herself, she could not know what it was like for other people to see colors (this is another manifestation of the dilemma faced by Jackson.)
From here on out (if not before), the deductions fall like a house of cards, and I can no longer even say "here's a valid deduction that is similar in spirit to yours."
In summary, this argument fails because it equivocates between two different things: on the one hand, knowledge of the physical state encoding the information content of some other item of knowledge, and on the other hand, that other item of knowledge itself.
You make it sound as though what preceded this sentence was an argument against premise one of my argument, but it was not. All you do is point out a pretty obvious, iterative distinction between a state and its description. That is not a counterexample to premise 1, nor any kind of reason to reject it. If you want to reject premise 1 you need to do better. Premise 1 seems perfectly in harmony with what you yourself referred to as canonical information theory.
Against premise 4 you state:
But that does not speak to premise 4 at all, within which there is no mention of knowledge, it is a metaphysical, not epistemological premise. The only epistemological premises of the argument are 6 and 7. Up to premise 4 all the issues are metaphysical. Note that the background assumption of the argument is a realism about information content, of course: i.e. there can be information content that is not the content of any actual mental state. But why would any physicalist object to such a realist assumption?
No it does not. You have misunderstood that premises 1 and 4 are metaphysical not epistemological in nature. Of course, if you want to discuss the possible collapse of that distinction, go at it, but it is probably not something a physicalist should attempt to do.
That is not the distinction I made. Please reread the post.
Quoting jkg20
I did, and I see that it can be read in the light of these being synonyms. I assume, therefore, that you have no objection to 'can be stated' being substituted for 'expressible' everywhere the latter is used in your latest argument?
Quoting jkg20
I am glad that this, at least, is obvious, but there is an implicit question here: suppose we have some system having information on account of being in physical state ?. if the corresponding propositions you have in mind are not a description of that state, then what are they? It is far from obvious that such propositions must exist, whether as a consequence of Shannon's information theory or of anything else. As things stand, proposition 1 lacks any justification.
Quoting jkg20
Premise 4 is "Anything that is physically encodeable is information content that is encodeable." Given the context, I took "information content" to mean the information content of knowledge. If it is not that, then what is it the content of?
Quoting InPitzotl
Indeed it is, and on the contrary, you seem to have overlooked (or, as you would put it, "are confused about") the relevance of this issue. It goes back to your attempt to claim that the possibility of behaviorally-invariant inverted spectra somehow invalidated my hypothesis, and I pointed out that mere possibility would not do; at the very least you would have to show actual prevalence. This section shows that, as a matter of fact, undetectable inverted spectra cases are sparse among all possibilities, and an explanation of why they are does not, of course, dispute the fact that they are.
Furthermore...Quoting InPitzotl
I see that you have no hesitation over needing more details when you wish to speculate on how things might be - but if you want to argue against my hypothesis with a speculation that is consistent with it, but which we would have no justification to believe if the mappings routinely differed between people as a first-order effect, then go ahead!
Quoting InPitzotl
On the contrary, as I pointed out in several cases, you have attempted to manufacture that impression by quoting out of context. And so it is here, also; you did not quote the rest of my response here, but only part of it, and elsewhere. For the record, here it is:
Quoting A Raybould
Quoting InPitzotl
Raising questions about specific points, as you have done here, is much more to-the-point than vague claims of vagueness, and I have no problem with answering them. The "learned lessons" are evolutionary adaptations. My expectation is more parsimonious than the hypothesis that first-order differences, between individuals, in their high-level functional responses to color stimuli, are pervasive. It is more parsimonious because the latter has a problem with ensuring that, of all the possible ways that a child might differ from its parents, only the ways that are behaviorally-close seem to arise. As for nature vs. nurture, nurture is not going to 'correct' a child into thinking that her tongue is red if her experiential correlates to how she sees her tongue maps close to those of grass and cucumbers, and distant from those of tomatoes, pimentos, and the setting sun.
Quoting InPitzotl
This is a non-sequitur. There will, in general, be behaviorally-observable consequences if human brains routinely have first-order differences in their functional responses to color stimuli, unless, mysteriously, this variation can only occur in the relatively few ways that are behaviorally inconsequential.
Quoting InPitzotl
Again, some relevant context is missing:
Quoting A Raybould
The premise that, in general, brain function is adaptive, is just one premise in my hypothesis. If you want to hang your case on refuting that particular premise, I rest my case!
Oh, you're not taking a position on the issue? Well, then I am not putting anything at risk by not responding until it is more than just creationists who are making that claim.
As for the italicised statement, this is an inaccurate paraphrase of my position, and therefore not germane. The evolutionary issue is just one point in an argument that involves ontogeny, the mechanism of inheritance, and the scope of variation: it is that if variation routinely produced first-order differences between offspring and their parents, adaptation would not occur.
Quoting InPitzotl
I will just note that this is no less vague than what I have been saying, but only to make a point about your mode of argumentation: what you have said here is perfectly reasonable speculation about how things might be, and it also satisfies the standard of falsifiability.
But more substantively, I admit that I am puzzled by why you would think the emphasized sentence would present a problem for my hypothesis - or if it does not, why you think it is relevant. Also, how might the developmental pathway distinguish between the latchings that are supposed to happen and those that are not? Are you proposing that there could be pervasive first-order differences in how this occurs in most individuals? If not, at what point could these differences manifest themselves?
Quoting InPitzotl
Talk about vagueness! I am not convinced that this makes it to the status of being a complete sentence, to the point where I cannot even guess what you mean here.
Quoting InPitzotl
You are not required to take a side, but if anyone floats a putative problem for my hypothesis, then I am, of course, going to probe it regardless of who, if anyone, might hold it. It is not all about you.
Quoting InPitzotl
Right at the start of this thread, and subsequently, I have said that we could simply agree to differ. Or we could consider the issue dispassionately, agreeing to differ on how plausible each argument is.
Quoting InPitzotl
Let me just point out here that if this name-the-gene standard of whatever-it-is-that-my-hypothesis-does-not-meet is applied consistently, then a good deal of evolutionary and general biological theory, including the fundamental one that life as we see it today is a result of natural selection, must be thrown out.
More substantively, it is completely unclear to me why my hypothesis requires a BM gene of any sort.
Quoting InPitzotl
What I am proposing is precisely that there is a plausible constraint, from empirical facts about biological inheritance and ontogeny, on the degree to which the high-level functional correlates of visual experience can vary between individuals.
Quoting InPitzotl
Not that I know of.
I had regarded your focus on L2 as just a case of unnecessary specificity, but when I looked for something justifying this specificity, I did not find any use of L1/L2 terminology with regard to color perception and experience - perhaps you can provide some references, and explain the relevance of your specificity?
Quoting InPitzotl
You have always been rather vague about what your objection is. We are in agreement, apparently, that it makes the grade as a falsifiable hypothesis. We are also in agreement, apparently, that it is at least several facts short of a theory. We disagree, apparently, on how plausible it is. On the key issue, however, of whether there is a plausible mechanism, for maintaining the observed first-order similarity between child and parent behavioral similarities, if it is the case that there is little commonality in the functional correlates of their visual experiences, neither of us are aware of one. You also still seem to be arguing against mistaken paraphrases of my argument. I feel that you have not yet made the case that a third party should summarily dismiss this hypothesis.
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Nevertheless, while I disagree that what I have presented here is too vague to be considered, it could be less vague, especially as my responses to misunderstandings are scattered over several posts. I intend to set it out more precisely, addressing the misunderstandings that have surfaced in this discussion. In doing so, I might come to the conclusion that it is not very plausible, and I will say so if I do.
There is alternative way of looking at your argument, by introducing premise 0: Everything that anyone could know about color vision is physically-encodable.
If we also assume that the argument through point 6 is valid (I am not saying I do!), we can conclude that, contrary to our intuitions, by time t, Mary knows everything that anyone could know about color vision, and therefore premise 7 cannot be added to this argument without invalidating it.
Given that the conclusion being sought here, by yourself and Jackson, is the antithesis of premise 0, it would be begging the question to deny that premise.
Stop right here. No. The possibility does not invalidate your hypothesis; that's not the point of it. Your hypothesis is inadequately justified. The possibilities simply highlight ways in which you can be wrong that you haven't actually addressed.
(FYI, your confusion of my rejection that your argument is adequate justification with invalidation of your hypothesis suggests the possibility that you're potentially susceptible to argument from fallacy, so I'd like to just point that out quickly).
Quoting A Raybould
We disagree over how well your justification supports your hypothesis.
Let me suggest a device... call it the surprise test. Your hypothesis suggests we see the same colors. Your support is that evolution basically just rolls that way. Let's just suppose someone proves your hypothesis wrong. Based on your presented hypothesis, and the support you've given for it, how surprised should I be to find it wrong?
Quoting A Raybould
Wrong criteria. "Adequately justified" is the phrase I've used, in multiple posts. It's not about dismissal, it's about the criteria for acceptance. So apply the surprise test. I feel you have not yet made a case sufficient for a third party to find it surprising, based on the case you've made, to find the hypothesis wrong.
Quoting A Raybould
Just to clarify, section 2 is talking about behaviorally undetectable inverted spectra, not undetectable inverted spectra. They're talking about different things that the guy with inverted spectra might do. If you can analyze his brain and find different representations of color, that's not what they mean.
Also, opponent color theory is mainstream (at least among color theorists). The analysis in section 2 of the SEP article didn't take into account the effects of color opponency on the modes of asymmetries they were discussing. Opponent color analysis is presumed to occur in the ganglia cells in the retina (cones connect to bipolar cells which connect to ganglia).
Quoting A Raybould
I hope you didn't search too hard, because the terms L0, L1, and L2 are simply defined by me in this thread for your specific benefit, for the purpose of this discussion, in this post.
Refer to this picture again:
L0 is spectral. This is the physical form of colors; objects reflect different frequencies of light by different amounts.
L1 is colorimetric:
Quoting Colorimetry
Colorimetry is based roughly on Grassmann's laws. L1 colors in short then are produced by our three cones under photopic conditions, and result from our trichromaticity. This collapses the full visible spectrum (L0) into three distinct cone channels. There is also the opponent color process, which is triggered primarily by processes in the eye (namely, ganglia cells that connect the signals from the cones, lying behind bipolar cells); so I'm lumping this into L1 (from a colorimetric perspective, opponent processes don't change anything; a spectral metamer is still that metamer and therefore still the same point in a colorimetric space). L1 colors are critical for experiences, because everything gates through them... if a person's eye cannot distinguish one metamer from another, then neither can his brain, and neither can he. But it's pretty out there to speculate that eyeballs experience color.
L2 is experiential. Experience is not produced in the eyeball; it's produced in the brain. Various places in your brain (visual cortex) are responsible for color analysis; here's an outline:
https://en.wikipedia.org/wiki/Colour_centre
...which I post as a raw link for emphasis (you really should read at least the first paragraph). Per a physicalist account, at some point, something in your brain generates consciousness, and your personhood arises. Within your mental scape, you experience colors, such as the colors in the color illusion displayed in this diagram. Since mind states are brain states, your experience should have a correlate. Those are L2 colors. Qualia are experiences:
Quoting Inverted Qualia
...and as such, inverted qualia are experiences. So qualia, as in the things being inverted in qualia inversion, are at L2, not at L1.
Quoting A Raybould
Oh that's easy... that falls out pretty much directly from this:
Quoting A Raybould
Quoting A Raybould
Quoting A Raybould
What are you talking about? These genes are just portions of a molecule, and they encode photopsins. Photopsins photoisomerize (fold in response to light), and this leads to the chain reaction that causes the cones to send signals. Change the shape of the photopsin and you change the absorption characteristics. For example, L and M's sensitivity curves are close, because erythrolabe and cyanolabe are chemically close, because the encodings for them on the associated genes encode for those particular close molecules.
Evolution doesn't hang in the balance, and if I suddenly managed to become a creationist, someone forgot to inform me. I've no idea where this nonsense came from... did you perhaps think those genes coded for color percepts?
ETA: Ah, it occurred to me that this nonsense may be due to you not understanding the question I asked you. You're proposing that same-experience in particular is selected due to it being an evolutionary adaptation. I'm asking you, why you think same-experience is subject to evolutionary pressures, which in my mind equates to the core of your hypothesis. But I'm guessing you're interpreting that as questioning evolution. Evolutionary adaptation is a process where selective pressures (what you're adapting to) influence the frequency of genes (in "competition" for genomic representation; i.e., alleles) in a gene pool (the change in allele frequency being evolution) to the degree that adaptive gene variants become predominant in a population. Your hypothesis presumes that same experience is adaptive, which further presumes that different experience would be maladaptive, which in turn means that there's a distinction between same experience and different experiences sufficient to warrant a distinction between an adaptive and a maladaptive behavior, in the sense that having same experiences of some particular sort somehow winds up increasing the probability that genes remain in the gene pool (e.g., more women with this trait survive to give birth; more men survive to mate; women give birth to more offspring; women find mates more easily, and so on). All of these are presumptions that basically equate to your core hypothesis, but you seem to argue for none of them, because you seem to think simply invoking the word "evolution" is enough to support your hypothesis. That's not true. Evolution only supports your hypothesis if it supports your hypothesis. For same experience to even be adaptive in the first place, it has to influence something that selective pressures can work on.
You have supplied no adequate reasoning as for why this would be the case; effectively, you just presumed it. (Mind you, you did attempt it, by pointing out someone else's argument in section 2 of that SEP article regarding asymmetries of perception, but since that can be explained in terms of L1 properties it's not quite adequate; note that I actually granted relevance to that argument, but have specific technical reasons to require more details). That is precisely what I'm calling guessing, and what I'm demanding you need to do before you can call your hypothesis adequately justified. If you cannot justify why same experience would be selected, you ipso facto have not justified that it is. So long as there's a giant presumptive gap in your argument, it does not rise to the level of adequacy.
Let me deal with this first, I'll speak to the more significant issues you raise in your previous reply to me, concerning the notion of information content, in a later post.
First, by introducing a premise to an argument you do not look at an argument in an alternative way, you change the argument. The premise you wish to introduce, in this context, is effectively the claim that physicalism is true for colour vision. Why would anyone presenting an argument with the aim of proving precisely the opposite accept that their argument can be "looked at in a different way" by adding a claim they oppose?
As I have pointed out on a number of occasions throughout our discussion, the physicalist can object to the claim, expressed in premise 7 of my latest argument, that Mary learns anything new when she sees that red tomato. As far as I can see, all Jackson has on his side for motivating acceptance of it is intuition, and not in the Cartesian sense of that word, but the colloquial sense in which it is akin to something like inspired guess work. Is intuition in that sense a sound basis for support? Maybe in the end all we have to go on is intuition, but that is a metaphilosophical question. However, if a physicalist does want to reject premise 7, note that they are rejecting the argument for reasons other than those first put forward by Churchland and later expanded on by Crane etc. Those objections were based on the claim that Jackson was guilty of more or less subtle forms of equivocation, which may well be true. My final argument, however, has removed those equivocations. Right from the beginning, you may remember, my aim was to circumvent Churchlandish responses to Jackson's argument, whilst leaving something behind that at least retained the spirit of Jackson's argument. If, now, after amendment in the form of my latest argument, the physicalist is actually being pushed into the corner of rejecting the claim that Mary learns anything new, then that particular aim has been accomplished. My adapted argument also focuses the issues where, to my mind, they need to be focussed, which is on the theory of content that lies in the shared representationalist background of both the physicalist and dualist positions....which takes us to the points you make in your other reply, which I will reflect upon a little more before responding.
There is nothing wrong with introducing a new premise into a discussion. If doing so were wrong, then we should reject your introduction, in your latest argument, of several premises that you had not raised in previous posts. Furthermore, in this case, premise 0 (the only additional premise; all the rest are yours) is not just any premise, it is the antithesis of your conclusion.
Of course, you would not want to accept premise 0 in any argument, but that is beside the point, as the purpose of debate in the search for knowledge is to persuade third parties of certain things (and even if you were to claim that you are arguing only for yourself, it would then be inconsistent with that claim to object to anyone else adopting any premise; furthermore, you would be in great jeopardy of fooling yourself if you did not examine your argument as a skeptic would.) The point is that you cannot simply reject the skeptic's assumption of the antithesis of your argument without begging the question.
As for your objection that this goes beyond your initial limited claims against Churchland's reply to Jackson, it would be inconsistent for you to do what you are doing - trying repeatedly to find an argument that holds up - while insisting that I must stick with only my first presentation of Churchland's argument (if the latter rule were applied consistently, there would be no debate about anything!) It would also be a contradiction to say that your latest argument is on-topic, while attempts to refute it are off-topic.
Your final argument has not removed the Churchland-Crane charge of equivocation, at least until you deal with the argument in my other reply above.
You seem to be under the impression that I am implying that premise 7 must be false, but the point here is, instead, that if your argument, for the proposition that all knowledge having physically-encodable information content is discursively-learnable, holds, then what non- question-begging reply do you have to the claim that Mary could have learned everything beforehand? One does not have to deny 7 to see that this is a problem for your argument.
Saying that premise 7 is just an intuition is not a get-out-of-jail card, logically speaking, as it does nothing to fix this problem. Also (somewhat unintuitively, perhaps), the reasons why one might believe any premise are not germane to validity.
Far from the physicalist being pushed into the corner of of rejecting the claim that Mary learns anything new, you are in the corner of having not yet given a non- question-begging reply to the problem of why Mary was unable to learn it before t1. That, of course, was in my original presentation of the Churchland/Crane reply to Jackson, so all the stuff about not addressing your original claim is beside the point, even if it were valid.
For reference, here is the counter-argument (points 1-7 copied from your original):
Which contradicts
[7]: Mary gains new knowledge when at t1 she sees a red thing for the first time.
As noted above, this does not necessarily imply that 7 is false, just that not all of the above can hold together.
Certainly there is not. However, the only acceptable premise to add to an argument that is presented as a complete argument is a premise that is hidden. The premise 0 that you are offering is certainly NOT a hidden premise of my argument.
If I gave an argument such as:
1. If there is a pattern to the universe then a non finite sentient being exists.
2. God is the only non finite sentient being
3. There is a pattern to the universe.
Therefore God exists
and then you come along and add premise 0,
0: All sentient entities are non divine.
and then you point out that by adding in premise 0 to the argument, we can draw out a contradiction with 2, all you are doing is rejecting the conclusion of the argument but without pinpointing the premises of it that you actually reject.
It is entirely to the point, since the argument is presented as complete and with a conclusion that physicalism is false for colour vision. Your premise is effectively the claim that physicalism is true for colour vision. It is for you to show that the argument has hidden premises that can be objected to OR that there are explicit premises that can be objected to. It is no use just coming along with another premise that is effectively just a rejection of the conclusion.
The argument requires not that Mary could have learned everything beforehand but that Mary could have learned everything physically encodeable because she can learn everything discursively learnable. The argument then adds a premise, 7, that she learns something new. If that premise is accepted, then it just follows from the other premises that what she learnsis not physically encodeable. There is no question begging going on.
Information content can of course be the content of knowledge, but since realism about information content is being assumed, it need not be the content of any actual knowledge. A simple example, if we assume realism quite generally, there could well be a fallen tree in a forest somewhere that no one has seen, the trunk of which has 70 rings. That physical state, which we can describe in a finite set of propositions at whatever level of detail we like, has the information content that that particular tree had survived 70 seasons of growth. Note the the information content is here identified with a single proposition. There may be more information content than just this encoded in the phyiscal state of the tree, but there is at least this. One fine day, someone walks through the forest and comes across the fallen tree and counts the rings and forms the belief that that particular tree had survived 70 seasons of growth. Let's assume a version of physicalism and that that person is in a physical state that we can identify with her believing that that tree had survived 70 seasons of growth. That physical state is describable by a finite set of propositions, this just follows from the finitude of human beings. The information content of that state is the same as the information content physically encoded in the tree itself, i.e. the information content identifiable by the proposition that that tree had survived 70 seasons of growth. Is it now clear to you what I mean by information content and that it need not necessarily be the content of anyone's actual knowledge, and so objections to premise 4 need to be metaphysical in nature and not epistemological, unless you wish to challenge realism.
I presume that the above talk about tree trunks makes it clear what the difference is between, on the one hand, the propositions that describe a phyiscal state which encodes some information content and, on the other, the propositions that describe the information content itself. As to the apparent issues you have with premise 1, it is in fact pretty much axiomatic for all theories of information content that I am aware of, that information content is identifiable by sets of propositions. It is certainly an assumption, not a consequence, of Shannon's theory of information transference, it is an assumption embedded in his free and undefined use of the term "message". It also runs through all of the philosophers who defend representational theories of mind, including physicalist representational theories of mind. It might be false, of course, but since it seems to be widely held amongst physicalists themselves, who are the target of the argument after all, I would like to see a counterexample or be referred to a relevant text where a physicalist non propositional account of information content is expounded. It might even be possible to come up with an actual argument that you could not have a coherent theory of informational content that allowed for content that was not identifable with finite sets of propositions, but on that particular point premise 1 is playing a card dealt to it by physicalists anyway, so I am content for the moment to sit on my laurels. However, if that is a point you want to pursue in detail, have at it.
But I am not simply rejecting it, I have presented an argument against it. Assuming the argument is deductively valid, which on the surface it is, the skeptic who wants to contest its soundness, and thus reject its conclusion, has a number of choices, whilst remaining rational. These include:
1: Show, by counterexample or some other means, that one or more of the explicit premises is false.
2: Show that there are hidden premises in the argument that are or might be false.
3: Linked to 2, show that there is an ambiguity in one or more of the premises and that when the ambiguity is clarified, the premises become false or at least possibly false.
4: Argue that we have more reason to reject the conclusion of the argument than we do to accept any of the premises.
4 would seem difficult to go for, after all physicalism and dualism are at least as much up for grabs as any of the premises of my argument. This leaves strategies 1 through to 3. Notice that I did not add.
5: Create a new argument by adding an entirely new premise to the existing ones that directly or implictly contradicts the arguments conclusion, thus turning the argument into a deductively invalid one. This is certainly a novel approach, but hardly a rational one.
Mary was unable to learn it before, because what she learns is not discursively learnable, and since everything that is physically encodeable is discursively learnable, according to the argument, what she learns is not physically encodeable either. So what does she learn? She learns what red things look like, and learning what red things look like is not discursively learnable. Of course; to be consistent I also have to say that what she learns is not identifiable by any finite set of propositions, so have I refuted myself by saying she learns what red things look like? Here I suppose we have to go Wittgensteinian and say that we do not identify what Mary learns with the expression "Mary learns what red things look like", but rather show or gesture at what she learns by doing so. The main point, in any case, is that whatever it is, it is not physically encodeable nor identifiable with any finite set of propositions.
I did not make any such objection. I pointed out simply that the original aim was to provide an argument that circumvented Churchland's objections about equivocation of epistemological notions. The argument I present may not be sound, but it does not equivocate in the way that Jackson's original argument does. Thus Churchland's objections are, I claim, circumvented. This is done by introducing specific metaphysical claims about informational content that are absent from Jackson's argument, so it should not be a real surprise that Churchland's epistemological objections become otiose. I am also not insisting that you stick to your guns. Within the bounds of rationality, you are free to find fault points in my argument. There may even be equivocation going on somewhere within it, and perhaps even epistemological equivocation, but thus far you have not identified that equivocation.
firstly. let me say that I have come to agree with you that I should say something about what physicalists assume about color vision, though it will not - and need not - be a complete explanation of how it works. I will say more on that below, in replying to your second post of this series.
Your claim that "the only acceptable premise to add to an argument that is presented as a complete argument is a premise that is hidden" only applies if it is being claimed that the resulting argument is effectively the same as the original. Any modification to an argument can be seen as creating a new one, and one can use any premises in a new one. In this case, I am creating a new argument, for the conclusion that at time t1, Mary already knows everything that could otherwise be learned from seeing a red thing for the first time.
This argument has several features of interest. Firstly, it contradicts your premise 7, and as such, it stands as a counter-argument: This argument and yours cannot both be valid and sound. So how could you show that this new one is either invalid or unsound?
This is another of its interesting points: except for one premise and two deductions, it is taken directly from your argument. If you could show that those parts are invalid or unsound, that would apply equally to your argument.
That leaves you with a few options. You could show it to be invalid by showing that lemma 5.1 (everything that anyone could know about color vision is discursively learnable) or conclusion 7.1 (at time t1, Mary already knows everything that could otherwise be learned from seeing a red thing for the first time) do not follow from the premises, but so far, you have not.
Your only other option is to show that the new premise (everything that anyone could know about color vision is physically-encodable) is unsound. You cannot simply say that your argument shows this to be so, as then your argument would be circular: "your argument against my argument fails, because my argument shows that your premise does not hold!" You could simply deny, without offering any additional argument, that my premise is false, but now we get to the third interesting point: this premise is the antithesis of your conclusion[1]. Therefore, you would be begging the question if you just did that. What else is there? That is the question I have been asking.
This is unlike your proof-of-God example, where the reply technically is a counter-argument, but not a useful one, as it does nothing more than deny the conclusion. While the only new premise I have introduced does that, I use several additional premises to show that your argument is not valid as it stands.
Let's follow Douglas Hofstadter's advice, and 'twiddle the knobs' on your tree-ring example.
When your subject discovers the tree trunk, no knowledge about its age can be learned discursively. It only becomes so once your subject has processed it, together with additional information that cannot be derived from the trunk. Note that a person who did not know the origin of tree rings would not form the proposition that the tree had survived 70 seasons of growth, and would not be able to communicate this fact (unless it was learned another way, which would be beside the point.)
Before any of that happens, the rings have to be perceived, which requires a modulated reflection of the light falling on it, stimulation of the viewer's receptor cells, and neural processing of the resulting signals.
Some of the physical changes in the neural system will be persistent, at least if the viewer has any memory at all of seeing the trunk. Let's call the physical state resulting from these changes due to perceiving the tree rings P (note that the physical state P is unique to each individual, as they have physically different brains simply as a result of not being made from the same atoms.). A physicalist can reasonably propose that P is essential to the subject knowing what it is like to perceive the rings.
Getting to the discursively-learnable proposition that "this tree has survived 70 seasons of growth" requires additional processing, which, for the first time, requires linguistic abilities, which are known to be located in a different region of the brain than visual processing. This will result in some additional state changes within the viewer's brain, and we can call the physical state resulting from these changes L. Note that the person who does not know the cause of tree rings does not form the proposition, and does not enter her version of state L, yet presumably does know what it is like to see the rings. Consequently, we can conclude that knowing this discursively-learnable knowledge is not necessary for knowing what it is like to see the rings.
(As it happens, one of Churchland's arguments for non-propositional qualia is that many animals lacking linguistic abilities can be shown to perceive, remember and compare colors (including to memories of colors), all without contemplating any propositions whatsoever.)
Regardless of how many ways this discursively-learnable information is the same as that encoded in the trunk's state, it is not identical to the latter information in at least three ways: 1) it is encoded as a physical state in the observer's brain, not a physical state of the trunk; 2) unlike the information in the trunk, it is the information content of someone's knowledge; 3) the trunk can be destroyed, while the observer continues to know something about its age when it fell.
Now let's introduce Mary, who knows all of completed physics. She has not seen the trunk, but has been given a complete physical description of it (there is no doubt that the physical description is communicable, and, in fact, it would be part of her complete knowledge of physics, which she has learned discursively.) From this description, she could deduce that the trunk has 70 rings, and, with the additional knowledge about the origin of tree rings (which is also part of her complete physical knowledge), she could achieve physical state L by deducing the discursively-learnable proposition that the tree has survived 70 seasons of growth.
Let's assume she can also deduce what her state P would be if she had seen the tree trunk, and give a description of it. In synthesising that description, she undergoes a third set of state changes, to state D, encoding (among other things) the propositions comprising the description of the state P. That state is not P itself.
To get to state P from this description of state P, Mary would need to target the specific neurons and synapses involved in P, and produce in them specific state changes. This would require a degree of connectedness and influence that certainly is not necessarily so, and has never been demonstrated to science (can you do it?) We cannot even just get the state of specific synapses, let alone change them.
And if we think that her total knowledge would give her this ability, then, per Dennett, she could get from D to P and would know what seeing the trunk is like - this is one of the horns of Jackson's dilemma again. In fact, all she would have to do would be to just modify the state of the first layer of neurons that the optic nerve connects to, replicating the effect of seeing the trunk, and so come to know what it is like to see it without having done so.
I don't generally like computer analogies, but there is a very appropriate one here: if I have a secure operating system, it will have plenty of internal-use-only state, and you will be unable to write a program that an unprivileged user could use to modify that state, even if you know everything there is to know about that operating system.
If you have read Curchland's Reply to Jackson, you will recognize this as being very similar in spirit to what he wrote there, and as he said, physicalists do not have to provide a complete and completely accurate account of vision in order to show that, quite plausibly, there is an entirely physical explanation for Mary not learning everything from her studies, even though she has full knowledge of physics (which is not the same as having all physically-encoded knowledge.) So long as this goes unanswered, Jackson's argument fails to make its case.
If it is the case that many philosophers, including many physicalist ones, hold that all information content is identifiable by sets of propositions (what, precisely, does 'identifiable by' mean?) then that might explain the popularity of 'old knowledge seen in a new way' replies to Jackson, which seem to me to be wrestling with a problem that has a much simpler answer. So long as philosophers like the Curchlands and Dennett are unconvinced by this view, I am not convinced that I am overlooking something obvious - and if I am, it should be easy to show that I am doing so, without appealing to authority.
This is all covered above - in particular, see the bit about circularity.
Again, see the above. It seems to me that your metaphysical claim is merely avoiding pertinent issues raised by Churchland and others. Metaphysical arguments have to make their case, just like any other.
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[1] I did not actually write "it is not the case that what Mary learns is not physically encodeable", but your conclusion does not actually refute either physicalism, or Churchland's reply, if she doesn't learn anything about color vision at t1. The conclusion you need here is something equivalent to what Jackson said, such as "at t1, Mary learns something that is not physically encodable." Of course, in your argument, you can get there directly by using premise 7, but I can also get to its antithesis directly from my conclusion that Mary does not learn anything at time t1.
I thought I had been clear about this point, and here is a quotation from an earlier post of mine, emphasis added:
"One can circumvent objections by changing the argument, which is effectively what I did: it is certainly not Jackson's original argument." I have never claimed that my arguments are the same as the original argument, if by "original argument" you mean Jackson's. Thus my claim about what is acceptable to add to my last argument stands. However, on reflection there is at least one "hidden" premises in that argument, so please see a new version of it below and treat it on its own merits. The thing it shares with Jackson's argument is the intuition pump that Mary does learn something new about colour vision when she sees that tomato for the first time.
None of this is relevant if we are assuming realism about information content, and most of what you talk about in your last post concerns how sentient beings might gain access to information content, but does not concern the what that content is in itself. Assuming realism about content allows the same content to be encoded in different ways. The points in the metaphysical premises of my argument concern identity of content conceived realistically, not identity of vehicle for that content. Nearly all of the points you make in your post concern differences in the vehicle for content and how different types of vehicle might come to encode the same content.
So, with my one concealed premise now exposed, here is the new argument against physicalism.
1 If physicalism is true, then everything anyone can know, in any sense of the term "know", about colour vision is physically encodeable.
2: All information content that is encodeable is identifiable by a finite set of propositions.
3: Any finite set of propositions is discursively learnable.
4: From 2 and 3; all information content that is encodeable is discursively learnable.
5: Anything that is physically encodeable is information content that is encodeable.
6: From 4 and 5 anything that is physically encodeable is discursively learnable.
7: At time t, Mary knows everything that is discursively learnable.
8: Mary gains new knowledge of some kind about colour vision when at t1 she sees a red thing for the first time.
9: From 6, if the new knowledge Mary gains at t1 is physically encodeable, then it is discursiveley learnable.
10: From 9 and 8, if the new knowledge Mary gains at t1 is discurvively learnable, then she did not know at t everything that is discursively learnable.
11: From 10 and 6, if the new Knowledge Mary gains at t1 is physically encodeable, then Mary did not know at t everything that is discursively learnable.
12: Since the consequent of 10 contradicts 7, by modus tollens what Mary learns is not physically encodeable.
13: From 1 and 12, physicalism is not true.
Note that if you now add your premise 0 to this argument, you get a deductively invalid argument. So, if you insist of creating an new argument by adding your premise 0 to the one above, your argument can be immediately rejected on the grounds that it is not deductively valid.
From what I gather, your issues with this argument focus on 2 and perhaps on 5. As indicated, everything you have thus far said against 5 conflates epistemological issues about how sentient creatures get access to information content, and metaphysical issues about information content itself. Do not misunderstand me, I am aware that realism about information content is a fraught issue. However, physicalism entails realism about information content, so if antirealism about information content is true, then physicalism is false anyway. So, for the purposes of arguing against physicalism it is perfectly acceptable to assume realism about content.
As a quick argument for premise 5, the very notion of encoding is that it is the conversion of data from one form to another, and data just is information content.
As concerns 2, I am not really appealing to authority. I am saying that it is a premise accepted or assumed by all physicalists and generally realist scientists and philosophers that deal with the notions of information, its encoding and its transference. Dennett and Churchland amongst them. However, there has been some recent work in philosophy that has attempted to make viable the notion of non propositional intentionality. If all intentional phenomena have content consisting entirely of information content, and not all intentional phenomena have content that is identifiable by propositions, then there will indeed be information content that is not identifiable by propositions, whatever "identifiable" means, and so premise 2 fails. However, if the objection to my argument is that there is non propositional intentionality, we are entering into very complex territory, and it is terrain that is very far from Churchland's fair equivocation points against Jackson's argument. If I have some spare time, I may well read a collection such as this Non Propositional Intentionality, but I feel I've said all I can or want to say about this for the moment.
I see that you still have no clear idea what my argument is, largely, it seems, as a result of your attempts to paraphrase it into something that you can dispute. I will reply with a lot more detail, but as I am off on a trip to the backwoods, that probably will not be until sometime next week.
I'm leaving for a week in the backwoods, so it will be more like next week before I reply, as there are many things here to correct.
One thing I did notice immediately, however, is that you have not yet given a clear and coherent explanation of what you mean when you use 'identifiable' / 'identified by', even though you use the term in a new premise. If you could do that, it would be helpful - for one thing, no-one should accept any premise containing the term, without there being a clear understanding of what it means.
Perhaps, but, 25 days ago. you responded specifically to this:
Quoting A Raybould
...with this:
Quoting A Raybould
Quoting A Raybould
So while you're speculating, is that because you're inexplicably the most important person in the world to me, or can you explain why my post count isn't a lot higher than it is given I'm just out to dispute people at random? (E.g., note that all this time, I haven't intervened on either side with your discussions with jkg20... isn't that curious?) Also, why do you feel the need to share your ridiculous speculations about my motivations with me, who one would think would be in a much better place to know said motivations?
Allow me to speculate about my own motivations to you... it's... perhaps... because 25 days ago you responded to the aforementioned quote with the aforementioned response, to me, and that you seem to be under the mistaken impression that this somehow should change my view about the thing I said that you quoted. Also, if you haven't guessed, color per se is a personal passion of mine. (Now doesn't that sound a lot more viable than he's-out-to-get-me [<-being literally some random guy on the internet]?)
So my issue with you is your alleged defense of this being "plausible" above the level of being "guesswork".
Quoting A Raybould
I'm sure you will.
I’d like to critique two objections that you pose to Jackson’s argument: the first regarding Jackson’s assertions about Mary’s knowledge, and second, your claim that Jackson’s argument contains a begging the question fallacy.
P1 of the version of this argument that you posted states, “Mary knew everything physical about the color red but has never seen the color red.” This refers to the fact that Mary’s knowledge of the color red encompasses everything except the actual experience of seeing it. However, you claim that this “implies Jackson is of the view that physicalism entails that knowing what brain-state corresponds to actually seeing red should evoke the brain-state of actually seeing red,” and that because of this, the argument “fails to achieve its intended objective of refuting physicalism.” I don’t see how this implication follows from P1. Even if Mary knew the exact brain-state that occurs when a person sees red (perhaps through brain imaging, descriptions, or information about the operation of the senses), she would not have any reason to experience the brain-state of actually seeing red, and she would still be gaining knowledge after seeing the color for herself. I acknowledge your assertion, based on this premise, that the knowledge of red and the experience of seeing red are both brain-states, but I think it fails to note one of Jackson’s points: Mary still gained new knowledge through the experience of seeing red, in a way that could not be taught to her. Further, even after acquiring the new brain-state of seeing red, she experiences yet another: if she goes back into the black-and-white bunker, she has the memory of seeing red, and is in the new state of having knowledge of experiencing red. Based on these points, I have a difficult time accepting your claim that the argument fails to refute physicalism.
You further claim that Jackson’s argument contains a begging the question fallacy, which you label as Premise 1a: “Complete physical knowledge can't account for actually seeing red.” This fallacy is present in the version of the argument that you posted, but I’m curious as to where it came from: is it your interpretation of the argument, or another’s? The versions of the argument that I’ve seen don’t suggest this fallacy. I’ll focus on the first half of the argument, because that’s the part that you’re taking issue with. Most versions that I’ve seen go something like:
P1: In the bunker, Mary knows every physical fact about the color red.
P2: Mary learns something about the color red after her release.
P3: Therefore, Mary didn’t have complete knowledge of the color red in the bunker.
This first part of the argument does show that there was some knowledge that Mary lacked, but I don't see a fallacy there, when it's organized and worded this way. It just illustrates Mary’s example, before the remainder of the argument states that physicalism is false. Therefore, I think that the idea of the fallacy that you mention doesn’t harm Jackson’s argument.
That experience consists - in part at least - of physical interactions. Thus, Mary did not know everything physical about the color red.
She did not know what it was like to experience color vision in the first person.
This does illustrate that first-person experience is not knowable from the third person.
It does not show that first-person experience is a non-physical phenomenon.
It’s entirely possible that there is a first-person experience to any physical phenomenon. In fact, it gets trickier if you try to assert that somehow humans have it but other things don’t, because then you have to posit something metaphysically different between humans and other physical things. Far more elegant to just grant that humans are like anything else — and that since we each know we have a first-person experience, we should assume by default that everything else does too.
No it doesn't. It simply declares it by the definition of the imaginary world in which the experiment takes place. We don't have an actual Mary who was actually told all there is to know about Red and who then actually reported a new sensation on leaving the room. We imagine such circumstances. All it tells us about is what we imagine to be the case. It tells us absolutely nothing at all about what actually is the case.
Reminds me of a comment made about emotions - actual feelings can't be put into words in such a way that they actually evoke those emotions. I guess Jackson's thoughts are in the same vein. There's something about immediate/direct/first-person experience that escapes description. Is it going to stay this way or are we just in need of the writer/speaker/interlocutor who has, let's just say, a way with words, having such powers of expression that faers words are capable of giving us the first-person experience I'm talking about here?
Impossibility, a concept I struggle with everyday...even the smallest things seem beyond my reach these days. Yet, the same seems not to be the case for others who seem to have already grabbed the low hanging fruit by the handful...they're now, quite literally, aiming for stars if you know what I mean, I await, as patiently as I can, and patience isn't my strong point, for the silver-tongued devil who will, for certain, put to words all that we regard, as of this moment, as the ineffable. Such a day/time will come (I hope). My fingers crossed, In this dream, here, there, I tossed.
-- Virginia Woolf
We can split the difference...between too much and too little there's something to be had.
It is physically impossible for one to know everything there is to know about the color red; to understand the current conventional standards; to be somewhat familiar with any ongoing and/or historical issues and/or philosophical 'problems' that may emerge within our discourse about these things; etc.; etc.; etc... if the candidate has never saw and discussed red things.
Knowing everything there is to know about the color(bandwidth/frequency of visible light) we call "red" requires having already seen and talked about red things. We're already talking about red stuff. We can pick out red things. We all pick out mostly the same things too; the red ones. We do all this long before we begin talking about the fact that we have and do. We have all sorts of thought and belief consisting of meaningful correlations drawn between red things and language use long before we begin taking those events into account.
These sorts of behaviours were happening on a grand scale long before we ever invented and/or otherwise acquired the technology that allowed us to begin talking about red things in terms of visible light frequencies and/or spectrums.<---------- That's not the beginning of the process of acquiring knowledge of red things. That's some of the discourse that emerged as a result of our already having picked red things out.
Mary's Room asks us to not consider the fact that knowing all that there is to know about red is a process that always begins with using the term "red" to pick out red things.<-------That requires seeing red things. Mary has never seen red things. Mary cannot possibly know everything there is to know about red.