Here, I explain why I don’t believe in sense data. I discussed this in Skepticism & the Veil of Perception and my Stanford Encyclopedia entry on “Sense Data” (https://stanford.library.usyd.edu.au/archives/spr2005/entries/sense-data/). (After I wrote that entry, they kept asking me to edit and update the entry. I had not realized that by writing the entry I was understood to be taking on a lifelong writing project. I did not want such a project. At some point, I told them that I just was not going to update it again. And so, many years later, they got someone else to write an entirely new entry (
Sense data, and all data, are information. As such, they only exist as an interpretable pattern in some physical medium. If I can have information in my mind or brain without harming myself, I can have sense data in my mind or brain. So arguing as if sense data must consist of distinct physical objects seems odd.
Maybe I am misframing this. Maybe data consist of the electrical charge in a circuit, or the dimple in a DVD, or the electrochemical state of my brain cells, and so in some sense they are physical objects. But if so, sense data are not distinct from my brain. I suppose we can think of my brain as just as dynamic as my thoughts and perceptions. But new perceptions don’t require more space.
Did Hume and the other theorists of sense data distinguish them from other sorts of data that we gain awareness of, interpret, and learn from? Or is all data sense data? Does this argument apply to all data, so we should conclude that datum is an incoherent category?
I clearly don’t really understand the point here. I need to think about this a lot more before I can understand well enough to agree or disagree. Maybe I have not read carefully enough. But the argument from limited space is wrong, unless I missed something big.
sense data approach wrong for 2. and 3. 2 -> because there is no mind-body problem, there's just the body. 3 -> because an object doesn't need to have the exact features it appears to have. our vision (like any other sense) evolved to take physical inputs and probabilistically work (ie, help our chances at surviving without too much cost to other systems/features).
i don't understand the need for the indeterminacy approach, though. not getting it as well as I have with other posts. thanks for sharing!
>You could say they appear in your head, in your brain. But it just sounds super naïve to suggest that when you see a tomato, a tiny tomato-shaped thing appears inside your head
If it's too naive,.no sense sense data theorist believes it. They believe that a sense datum of f a tomato is a thing of type "representation" , not a thing of type " tomato". A photograph of a tomato is a photoograph, a painting of a tomato is a painting. And an intermediate neural representation is a latter of neural activation.
I've been pretty consistently confused about this debate, but I think my confusion might just be because of the words used in the debate. I'm honestly not sure.
...
You say, "There is no image of a blogpost written by me in your mind."
I introspect and see with my mind's eyes your blogpost. I reply, "Of course the image is there, I can see it right now!"
You reply, "No, what you see is the actual blogpost which is outside the mind."
I reply, "If what I am seeing is the actual blogpost, why can I still see it if I shut my eyes? Why can I no longer see it even if my eyes are looking at it when I am thinking about something else?"
I suppose you reply, "In such cases, you aren't actually seeing anything because perception is factive (i.e.. if you see P, then P must be true)."
I reply, "I do not use the word 'perception' to talk about anything factive. Get rid of the factive requirement, and just talk about the thing you apply the requirement to. Clearly, I can have that, which I call a perception, while I shut my eyes or am thinking about something else. What is the thing you apply a factive requirement to, if not an image in the mind?"
You reply, "It is a state with propositional content to the effect that there seems to be a blogpost written by me."
I reply, "And so such states count for you as perceptions when they are veridical (and thus satisfy the factive requirement), but we have such states both when they are veridical and when they are not?"
I think you'd reply, "Yes."
I reply, "Okay, so why aren't those states just mental images in the mind? Why couldn't a state have propositional content to the effect that there seems to be a blogpost written by you just by consisting of a mental image of such a blogpost?"
(I think the above question is what the actual debate is about, but nobody I've read ever words the debate in terms of whether a state can have propositional content by consisting of a mental image. This is what leaves me confused.)
You reply, "First, because there is no space for that mental image anywhere, and, second, perceptions can be indeterminate."
I reply, "First, on your view, the blogpost I see is a veridical perception and so takes up the space the blogpost does on my computer screen. Yet, you seem to have left yourself with no space for the non-veridical states with propositional content we discussed earlier. Where is the response to this series of questions which I imagine when I shut my eyes? It appears to me to take up space, but what space? Isn't it clearly in the mind?
Second, you agree that propositional content can be indeterminate. If so, why couldn't a state which has propositional content by consisting of a mental image be indeterminate? Is the idea just that mental images can't be indeterminate? Why not? You call such images objects, but I could similarly call propositional content an object and that wouldn't prevent it from being indeterminate. What feature (not what category they belong to, but perhaps what property in light of which they count as a member of that category) of mental images would entail that they are always determinate?"
I suppose you'd reply, "First, the response you imagine when you close your eyes does not exist and so does not take up any space anywhere, it just appears to exist and take up space, but this appearance does not consist of any mental image and so, despite appearances, there is no need for any space for any such mental image.
Second, mental images are supposed to have the properties of the things they represent and in order to have such properties they must be the sort of thing which can have the same properties that everyday objects have, and only determinate things are the sort of things which can do that. Only determinate things can be red like apples are, or round like oranges are, or what have you."
...
Am I misunderstanding something? Because if I'm not, the entire literature on this subject is put in terms that are wildly misleading to me.
I'm also not sure why we should accept the "despite appearances" bit. If an appearance that P provides defeasible justification that P and if there appears to be something which takes up space when I imagine your response, why shouldn't we conclude that (1) there is a mental image which takes up such space and (2) it takes up mental space in the mind rather than physical space?
"Hume says that when you move farther away from a table, the table you see looks smaller. But the real table does not get smaller. Therefore, what you’re really seeing must be only a mental image, not the real table"
It looks further away, and smal!er, and further away because it's smaller. We don't have a physical mechanism to judge distance directly, so it is inferred from clues, and one of the clues is apparent size. A receding object casts a shrinking image on the retina,and that's our basis for inferring that's it's receding.
Once the brain has decided that the object is recedijng, the hypothesis that the image image is shrinking because the object is shrinking is thrown out...and in that sense the object does not "look smaller". But the small or shrinking retinal.image is the basis of the whole thing.
This sounds like the sort of critique that would be made by followers of perceptual psychologist James J. Gibson. Would you consider yourself a Gibsonian direct perceptionist?
This is my favorite argument against sense data. "
I'm completely unmoved by it.
"Sense data, again, are supposed to have exactly their apparent properties.
The problem is that objects can have indeterminate appearances"
So? "Exact apparent properties" doesn't mean. "apparent properties that are exact".. A cloud of fog should look vague and indistinct. A sense datum veridically representing a cloud of fog should have an apparent property of vagueness, and the perceiver should. be in no doubt about that.
I generally agree with Jay Rollins here. Is this refuting a definition of sense data that came about before modern neuroscience?
Outside of a particular term of art, my naive interpretation of the words “sense data” is simply the input to our neural processes: electrical impulses, neurotransmitters. The physical mechanisms by which we perceive the apple. Yes there is a real apple there, and real light bounces into our eyes, and that light ultimately gets converted to signals through our optic nerves. /That/ is sense data to me, naively.
The issue is that it is a chained and complex process to go from light to understanding of an apple. Light is _one_ possible input to the process, but it is not a necessary one. Hence mentally picturing something, dreaming, and visually hallucinating all occur and all light up the visual cortex.
We may label only the inputs that come from the outside world as sense data. That is the only data sensed! But what we perceive is something later in the process, and that process is not restricted to physically sensed information.
Or: I think The Matrix got this one right. Stimulate the nerves in just the right way and there’s no perceptible difference between reality and simulated reality.
I agree with the general sentiment of this post, but allow me to massage it a bit. Everything we are aware of is a ‘mental state’, let us say, some primary idea of an object we are focussed on, which is conceptually related in space and time (also ideas, organising ideas) to countless other ideas. This state of ideas changes and accommodates change itself as an organising idea to maintain the integrity of relations among ideas. Some ideas are integrated in a particular, persistent way. We call them physical objects, and tomato is an example of one of these. We can recognise a tomato precisely because we know what a tomato is like, what kind of lower level ideas (properties) an object “tomato” has. We have developed all these ideas over millions of years by interacting with beings of the same kind, together with the central idea, the source and locus of ideas: the conscious self. So when we see a tomato we are aware of an actual tomato, a physical tomato, a true object, meaning a tomato integrated in the context/realm of ideas shared (similarly integrated) by all other beings of the same kind (conscious, rational agents like me). The result of this shared integration is not an individual action but an accrued social effort older than we have a record of, and this makes it for all practical purposes independent of individual mental manipulation; we are subordinate to this realm in order to ‘make sense’ of anything and to be a ‘self’. From this shared context of restricted individual influence to physical means vis a vis the capacity for relatively free conceptual manipulation (thought) we have collectively derived ideas like mind, thought, brain, sense data, perception, atoms and of course what kind of properties make up a ‘real’ tomato.
A sense datum doesnt have to be a conventional object. To use an analogy, there is something inside.a computer that corresponds to the Super Mario you see on the screen ... but it isn't a.tiny Italian plumber....it's a diffuse pattern of data and computation.
Deams and hallucinations .are among the strongest evidence for a sense datum theory. If you can perceive something that isn't there at all... if you can be in a:state of as-if perceiving something that isn't there at all ... then it's a hell of a stretch to say you are misperceiving a real thing.
"There is no pink or elephant-shaped thing that you perceive or have awareness of. There is only a state of falsely seeming to perceive a pink, elephant-shaped thing."
Which might or might not involve a proxy, a,pattern of neural activation as if you saw a pink elephant. The fact that it is false, non veridical, does not tell us out how it is false.
It might be the case that dreams and hallucinations use an entirely different mechanism to ordinary veridical perception .. but it might not. You can't tell using armchair argumentation, you have to investigate the brain.
"(b) [you] find, as you move closer to the sign, that the letters appear to change their shapes. You’d then conclude that you were hallucinating when looking at the sign from a distance."
"Hallucinate" is a strong word. I wouldn't call a slight misperception a hallucination. And I would absolutely say that the letters seem to change their shape as I move closer. They stop seeming to be blurry. And blurriness seems to me to be a determinate property, you can easily recreate blurry letters of a large size in a photo editor on a computer. And I can't imagine what it would be like to experience something that appears to be indeterminate as opposed to blurry.
I also wonder what your view implies regarding the cartesian intuition that we can't be wrong about our present conscious states if our experiences are indeterminate and there is no fact of the matter exactly what experience I was going through.
Sense data, and all data, are information. As such, they only exist as an interpretable pattern in some physical medium. If I can have information in my mind or brain without harming myself, I can have sense data in my mind or brain. So arguing as if sense data must consist of distinct physical objects seems odd.
Maybe I am misframing this. Maybe data consist of the electrical charge in a circuit, or the dimple in a DVD, or the electrochemical state of my brain cells, and so in some sense they are physical objects. But if so, sense data are not distinct from my brain. I suppose we can think of my brain as just as dynamic as my thoughts and perceptions. But new perceptions don’t require more space.
Did Hume and the other theorists of sense data distinguish them from other sorts of data that we gain awareness of, interpret, and learn from? Or is all data sense data? Does this argument apply to all data, so we should conclude that datum is an incoherent category?
I clearly don’t really understand the point here. I need to think about this a lot more before I can understand well enough to agree or disagree. Maybe I have not read carefully enough. But the argument from limited space is wrong, unless I missed something big.
sense data approach wrong for 2. and 3. 2 -> because there is no mind-body problem, there's just the body. 3 -> because an object doesn't need to have the exact features it appears to have. our vision (like any other sense) evolved to take physical inputs and probabilistically work (ie, help our chances at surviving without too much cost to other systems/features).
i don't understand the need for the indeterminacy approach, though. not getting it as well as I have with other posts. thanks for sharing!
>You could say they appear in your head, in your brain. But it just sounds super naïve to suggest that when you see a tomato, a tiny tomato-shaped thing appears inside your head
If it's too naive,.no sense sense data theorist believes it. They believe that a sense datum of f a tomato is a thing of type "representation" , not a thing of type " tomato". A photograph of a tomato is a photoograph, a painting of a tomato is a painting. And an intermediate neural representation is a latter of neural activation.
I've been pretty consistently confused about this debate, but I think my confusion might just be because of the words used in the debate. I'm honestly not sure.
...
You say, "There is no image of a blogpost written by me in your mind."
I introspect and see with my mind's eyes your blogpost. I reply, "Of course the image is there, I can see it right now!"
You reply, "No, what you see is the actual blogpost which is outside the mind."
I reply, "If what I am seeing is the actual blogpost, why can I still see it if I shut my eyes? Why can I no longer see it even if my eyes are looking at it when I am thinking about something else?"
I suppose you reply, "In such cases, you aren't actually seeing anything because perception is factive (i.e.. if you see P, then P must be true)."
I reply, "I do not use the word 'perception' to talk about anything factive. Get rid of the factive requirement, and just talk about the thing you apply the requirement to. Clearly, I can have that, which I call a perception, while I shut my eyes or am thinking about something else. What is the thing you apply a factive requirement to, if not an image in the mind?"
You reply, "It is a state with propositional content to the effect that there seems to be a blogpost written by me."
I reply, "And so such states count for you as perceptions when they are veridical (and thus satisfy the factive requirement), but we have such states both when they are veridical and when they are not?"
I think you'd reply, "Yes."
I reply, "Okay, so why aren't those states just mental images in the mind? Why couldn't a state have propositional content to the effect that there seems to be a blogpost written by you just by consisting of a mental image of such a blogpost?"
(I think the above question is what the actual debate is about, but nobody I've read ever words the debate in terms of whether a state can have propositional content by consisting of a mental image. This is what leaves me confused.)
You reply, "First, because there is no space for that mental image anywhere, and, second, perceptions can be indeterminate."
I reply, "First, on your view, the blogpost I see is a veridical perception and so takes up the space the blogpost does on my computer screen. Yet, you seem to have left yourself with no space for the non-veridical states with propositional content we discussed earlier. Where is the response to this series of questions which I imagine when I shut my eyes? It appears to me to take up space, but what space? Isn't it clearly in the mind?
Second, you agree that propositional content can be indeterminate. If so, why couldn't a state which has propositional content by consisting of a mental image be indeterminate? Is the idea just that mental images can't be indeterminate? Why not? You call such images objects, but I could similarly call propositional content an object and that wouldn't prevent it from being indeterminate. What feature (not what category they belong to, but perhaps what property in light of which they count as a member of that category) of mental images would entail that they are always determinate?"
I suppose you'd reply, "First, the response you imagine when you close your eyes does not exist and so does not take up any space anywhere, it just appears to exist and take up space, but this appearance does not consist of any mental image and so, despite appearances, there is no need for any space for any such mental image.
Second, mental images are supposed to have the properties of the things they represent and in order to have such properties they must be the sort of thing which can have the same properties that everyday objects have, and only determinate things are the sort of things which can do that. Only determinate things can be red like apples are, or round like oranges are, or what have you."
...
Am I misunderstanding something? Because if I'm not, the entire literature on this subject is put in terms that are wildly misleading to me.
I'm also not sure why we should accept the "despite appearances" bit. If an appearance that P provides defeasible justification that P and if there appears to be something which takes up space when I imagine your response, why shouldn't we conclude that (1) there is a mental image which takes up such space and (2) it takes up mental space in the mind rather than physical space?
"Hume says that when you move farther away from a table, the table you see looks smaller. But the real table does not get smaller. Therefore, what you’re really seeing must be only a mental image, not the real table"
It looks further away, and smal!er, and further away because it's smaller. We don't have a physical mechanism to judge distance directly, so it is inferred from clues, and one of the clues is apparent size. A receding object casts a shrinking image on the retina,and that's our basis for inferring that's it's receding.
Once the brain has decided that the object is recedijng, the hypothesis that the image image is shrinking because the object is shrinking is thrown out...and in that sense the object does not "look smaller". But the small or shrinking retinal.image is the basis of the whole thing.
This sounds like the sort of critique that would be made by followers of perceptual psychologist James J. Gibson. Would you consider yourself a Gibsonian direct perceptionist?
"The Argument from Indeterminacy
This is my favorite argument against sense data. "
I'm completely unmoved by it.
"Sense data, again, are supposed to have exactly their apparent properties.
The problem is that objects can have indeterminate appearances"
So? "Exact apparent properties" doesn't mean. "apparent properties that are exact".. A cloud of fog should look vague and indistinct. A sense datum veridically representing a cloud of fog should have an apparent property of vagueness, and the perceiver should. be in no doubt about that.
I generally agree with Jay Rollins here. Is this refuting a definition of sense data that came about before modern neuroscience?
Outside of a particular term of art, my naive interpretation of the words “sense data” is simply the input to our neural processes: electrical impulses, neurotransmitters. The physical mechanisms by which we perceive the apple. Yes there is a real apple there, and real light bounces into our eyes, and that light ultimately gets converted to signals through our optic nerves. /That/ is sense data to me, naively.
The issue is that it is a chained and complex process to go from light to understanding of an apple. Light is _one_ possible input to the process, but it is not a necessary one. Hence mentally picturing something, dreaming, and visually hallucinating all occur and all light up the visual cortex.
We may label only the inputs that come from the outside world as sense data. That is the only data sensed! But what we perceive is something later in the process, and that process is not restricted to physically sensed information.
Or: I think The Matrix got this one right. Stimulate the nerves in just the right way and there’s no perceptible difference between reality and simulated reality.
I agree with the general sentiment of this post, but allow me to massage it a bit. Everything we are aware of is a ‘mental state’, let us say, some primary idea of an object we are focussed on, which is conceptually related in space and time (also ideas, organising ideas) to countless other ideas. This state of ideas changes and accommodates change itself as an organising idea to maintain the integrity of relations among ideas. Some ideas are integrated in a particular, persistent way. We call them physical objects, and tomato is an example of one of these. We can recognise a tomato precisely because we know what a tomato is like, what kind of lower level ideas (properties) an object “tomato” has. We have developed all these ideas over millions of years by interacting with beings of the same kind, together with the central idea, the source and locus of ideas: the conscious self. So when we see a tomato we are aware of an actual tomato, a physical tomato, a true object, meaning a tomato integrated in the context/realm of ideas shared (similarly integrated) by all other beings of the same kind (conscious, rational agents like me). The result of this shared integration is not an individual action but an accrued social effort older than we have a record of, and this makes it for all practical purposes independent of individual mental manipulation; we are subordinate to this realm in order to ‘make sense’ of anything and to be a ‘self’. From this shared context of restricted individual influence to physical means vis a vis the capacity for relatively free conceptual manipulation (thought) we have collectively derived ideas like mind, thought, brain, sense data, perception, atoms and of course what kind of properties make up a ‘real’ tomato.
A sense datum doesnt have to be a conventional object. To use an analogy, there is something inside.a computer that corresponds to the Super Mario you see on the screen ... but it isn't a.tiny Italian plumber....it's a diffuse pattern of data and computation.
Deams and hallucinations .are among the strongest evidence for a sense datum theory. If you can perceive something that isn't there at all... if you can be in a:state of as-if perceiving something that isn't there at all ... then it's a hell of a stretch to say you are misperceiving a real thing.
"There is no pink or elephant-shaped thing that you perceive or have awareness of. There is only a state of falsely seeming to perceive a pink, elephant-shaped thing."
Which might or might not involve a proxy, a,pattern of neural activation as if you saw a pink elephant. The fact that it is false, non veridical, does not tell us out how it is false.
It might be the case that dreams and hallucinations use an entirely different mechanism to ordinary veridical perception .. but it might not. You can't tell using armchair argumentation, you have to investigate the brain.
"(b) [you] find, as you move closer to the sign, that the letters appear to change their shapes. You’d then conclude that you were hallucinating when looking at the sign from a distance."
"Hallucinate" is a strong word. I wouldn't call a slight misperception a hallucination. And I would absolutely say that the letters seem to change their shape as I move closer. They stop seeming to be blurry. And blurriness seems to me to be a determinate property, you can easily recreate blurry letters of a large size in a photo editor on a computer. And I can't imagine what it would be like to experience something that appears to be indeterminate as opposed to blurry.
I also wonder what your view implies regarding the cartesian intuition that we can't be wrong about our present conscious states if our experiences are indeterminate and there is no fact of the matter exactly what experience I was going through.