You don't have to think of experience as a collection of ghosts, though. You can just note that you do see red, and leave it unexplained exactly how. — frank

That seems tantamount to accepting the ghost as ghost? Which could turn out to be appropriate, of course. I'm just pointing out an alternative.

That seems tantamount to accepting the ghost as ghost? Which could turn out to be appropriate, of course. I'm just pointing out an alternative. — bongo fury

Newton was accused of introducing mysticism into physics with the idea of gravity. He protested that he didn't know what it was, but was just pointing out that it is. If someone accepted Newton's answer to the charge of mysticism, would that be tantamount to accepting that gravity is mystical?

Semantic direct realism doesn't work on a number of fronts. One is because of multiple realizability, which, as the SEP article explains, is the reason non-reductionism is the prevailing view in philosophy of mind. Pain doesn't reduce to particular actions for the same reason it can't be reduced to mental states.

would that be tantamount to accepting that gravity is mystical? — frank

There's mystical and there's mystical. There's an invisible pull between two bodies proportional to their masses, and there's a picture show in the head.

As for SDR, I'm not at all sure I'm on side with any brand of realism, inasmuch as they mostly seem to discuss the possibility of some kind of inner ghost making contact with the outer world.

:up:

.

Having red or blue mental images in the brain, to meet that purpose, is kind of having a ghost in the machine.

Having the brain reach for suitable words or pictures, isn't. And, even better, it suggests a likely origin of our tendency to imagine that we accommodate the ghostly entities. — bongo fury

:up:

I don't understand the issue. Pain isn't a property of external world objects. I feel pain. There's no problem here. Colours aren't a property of external world objects. I see colours. Suddenly there's a problem? — Michael

Yes. Primarily 'feeling' is a term we use for multiple meanings, one of which is a summary of your mental state "how are you feeling today?". So "I feel pain" and "I feel the grass" have two different meanings. The former being used in the sense of describing a state of mind, the latter in the sense of touch-sensation.

You specifically wanted to talk about the problem of epistemology with regard to perception and not want to get caught up in semantics. Given the, it is only this latter sense of 'feel' we're interested in here, the one which is about you sensing the external world with your nervous system.

There are models which make sense of internal 'feelings' (summaries of mental states) in a biological framework, but they'd be of no use to us here since you want to discuss perception, and summarising one's mental state is not an act of perception.

When our nerves are stimulated in certain ways, we feel pain. That pain, even though an "internal" thing, indicates that something is going on outside us, and we react accordingly. — Michael

So this is muddled. When our nerves are stimulated in certain ways we 'feel' the cause of that stimulation (using feel in the sense of sensory perception). If I hit you you would say that you felt my fist contact your arm. You might also make a self report about your mental state "I feel in pain", but that's irrelevant to perception and so outside of the scope of this conversation.

When our temperature is lowered sufficiently, we feel cold. That cold, even though an "internal" thing, indicates that something is going on outside us, and we react accordingly. — Michael

Again, note none of your leading examples are yet straying from the use of the ambiguous word 'feel'...

When our eyes are stimulated in certain ways, we see red. That red, even though an "internal" thing, indicates that something is going on outside us, and we react accordingly. — Michael

... and now substitute 'see' as if it were a given that it had the same dual meaning as 'feel'. No one asks "How are you seeing today", no one says "when you girlfriend left you, how did that make you see?"

'See' does not have this dual meaning where it's also describing a self-report about mental states.

Hence when you say "I see a tree" we're only describing your sensory perception, your estimation of the causes of external stimulation of your sensory perception nodes of your nervous system.

So to say "I see 'red'" but have 'red' as being some internal state, you'd have to posit that those sensory nodes somehow also terminate internally, that they sense other parts of the same system.

Effect: private sense data that cannot be publicly verified as either true or false. — Richard B

I think everyone would agree with this, apart from perhaps a psychic empath.

Cause: an unknowable something that is out of reach because all we know for certain is our private sense data. — Richard B

Very true.

But perhaps you need to have brain activity that succeeds in associating the red ball with red surfaces generally, and the blue ball with blue surfaces generally?

Having red or blue mental images in the brain, to meet that purpose, is kind of having a ghost in the machine.

Having the brain reach for suitable words or pictures, isn't. And, even better, it suggests a likely origin of our tendency to imagine that we accommodate the ghostly entities. — bongo fury

I'm not totally averse to saying that mental phenomena just is brain activity. What I'm averse to is the claim that being in pain has something to do with saying or thinking "I am in pain" or taking aspirin or performing some other activity that other people use to judge me to be in pain, or the claim that pain is a property of the external world object that causes me to feel pain.

Yes. Primarily 'feeling' is a term we use for multiple meanings, one of which is a summary of your mental state "how are you feeling today?". So "I feel pain" and "I feel the grass" have two different meanings. The former being used in the sense of describing a state of mind, the latter in the sense of touch-sensation.

You specifically wanted to talk about the problem of epistemology with regard to perception and not want to get caught up in semantics. Given the, it is only this latter sense of 'feel' we're interested in here, the one which is about you sensing the external world with your nervous system. — Isaac

The epistemological problem of perception concerns the relationship between the phenomenology of experience and the mind-independent properties of external world objects. The indirect realist argues that what we feel in the former sense is a mental representation of what we feel in the latter sense; that what we feel in the former sense is not a property of what we feel in the latter sense.

In the case of the dress, some people see in the former sense white and gold and others see in the former sense black and blue. The white and gold that I see in the former sense are not properties of the dress that I see in the latter sense, but are mental phenomena that result from brain activity in response to stimulation by the light reflected by the photo.

Given that it is what I see in the former sense that determines how I understand and describe what I see in the latter sense, and as what I see in the former sense is not a property of what I see in the latter sense, there is an epistemological problem of perception. That I can see in the former sense that the dress is white and gold tells me nothing about the dress I see in the latter sense (except the trivial fact that it causes me to see in the former sense white and gold).

The indirect realist argues that what we feel in the former sense is a mental representation of what we feel in the latter sense; that what we feel in the former sense is not a property of what we feel in the latter sense. — Michael

Right. So what's the point of it?

If what we're sensing is not a property of anything external to the system doing the sensing, then why is that system sensing anything at all? Why is it only detecting properties it itself has made up?

What's your evolutionary model for how this situation came about in all biological creatures (or how it evolved out of one in humans), what mechanisms were behind such an evolution, how could it possibly have sustained the enormous amounts of calories such activities involve without causing sufficient biological cost to have evolved out?

I'm not getting anything of the meta-biological framework your theory sits within.

Right. So what's the point of it?

If what we're sensing is not a property of anything external to the system doing the sensing, then why is that system sensing anything at all? Why is it only detecting properties it itself has made up? — Isaac

I don't understand your question. I don't know much about why putting my hand in the fire cases me to feel (in the former) sense pain. I just know that it does.

I'm not getting anything of the meta-biological framework your theory sits within.

This isn't my theory. It's what science has shown to be the case. You stimulate my nerves (or my brain) a certain way and I feel pain. That pain is in my head, not out in the world to discover.

I don't understand your question. — Michael

I start from a principle that features of human physiology evolved within a system where their cost did not exceed their survival benefit. In such a system, it would be practically impossible for the huge amount of calories mental processes consumes to be justified if all it did was detect internal states of the same system, I can't see the survival advantage.

So I'm asking you what the survival advantage is, or what your alternative meta-biological theory is. Without either I can't see how you can sustain the model with such glaring holes in it.

I just know that it does. — Michael

Here's a model of pain...

1. an external state stimulates a nociceptive nerve ending
2. that signal (among hundreds of others) travels through an hierarchical system of prediction engines which attempt to output a response appropriate to reducing the uncertainty of that external state (either by manipulating the external state by acting on it, or by refining the model by further focussed investigation)
3. one of those outputs is to alter the release rate of certain hormones which in turn influence the output of other prediction engines (shifting their priors slightly in favour of certain types of output)
4. This state of affairs, this hormone affected setup, if you were to report it (either to yourself, or to others) you would use the expression "feeling pain" to describe.

If the above were the case then how would it clash with what you claim here to "know" about your feeling pain. If the last thing your brain does, after going through the process of predicting the state of external nodes, is to render a self-report which you respond to as a 'feeling of pain', then how would you distinguish that from the actual functioning of your brain in response to external stimuli?

I start from a principle that features of human physiology evolved within a system where their cost did not exceed their survival benefit. In such a system, it would be practically impossible for the huge amount of calories mental processes consumes to be justified if all it did was detect internal states of the same system, I can't see the survival advantage.

So I'm asking you what the survival advantage is, or what your alternative meta-biological theory is. Without either I can't see how you can sustain the model with such glaring holes in it. — Isaac

Theories need to fit the facts, not the other way around, and it is a fact that the pain I feel isn't a property of the fire that causes me to feel pain.

So either there is a survival advantage to feeling pain, or feeling pain just happens to be a deterministic effect of something else that gives us a survival advantage (e.g. a complex brain that is able to effectively respond to stimulation).

Here's a model of pain...

1. an external state (light) stimulates a nociceptive nerve ending
2. that signal (among hundreds of others) travels through an hierarchical system of prediction engines which attempt to output a response appropriate to reducing the uncertainty of that external state (either by manipulating the external state by acting on it, or by refining the model by further focussed investigation)
3. one of those outputs is to alter the release rate of certain hormones which in turn influence the output of other prediction engines (shifting their priors slightly in favour of certain types of output)
4. This state of affairs, this hormone affected setup, if you were to report it (either to yourself, or to others) you would use the expression "feeling pain" to describe.

If the above were the case then how would it clash with what you claim here to "know" about your feeling pain. If the last thing your brain does, after going through the process of predicting the state of external nodes, is to render a self-report which you respond to as a 'feeling of pain', then how would you distinguish that from the actual functioning of your brain in response to external stimuli? — Isaac

I don't quite understand what you're trying to say here. It appears that this accepts that pain isn't a property of the external state that stimulates a nociceptive nerve ending, but is an "inner" state. I agree with the principle of that, but would extend it to other things, such as "seeing red", e.g.:

1. an external state stimulates the rods and cones in one's eyes
2. that signal (among hundreds of others) travels through an hierarchical system of prediction engines which attempt to output a response appropriate to reducing the uncertainty of that external state (either by manipulating the external state by acting on it, or by refining the model by further focussed investigation)
3. one of those outputs is to alter the release rate of certain hormones which in turn influence the output of other prediction engines (shifting their priors slightly in favour of certain types of output)
4. This state of affairs, this hormone affected setup, if you were to report it (either to yourself, or to others) you would use the expression "seeing red" to describe.

The key point is that red, like pain, isn't a property of the external stimulus.

I might go further and say that feeling pain and seeing red isn't just a "hormone affected setup" but is some supervenient mental phenomena, but as a first step we need to at least agree that red and pain aren't properties of external world objects before we can progress further.

This is where it gets interesting. How divergent can someone get with their apparent language of colors... — Richard B

Very divergent, e.g. in the case of synesthesia. Whereas most of us only see colours in response to light, some also see colours in response to sound (chromesthesia).

Sure. I'm not totally averse to saying that mental phenomena just is brain activity. What I'm averse to is the claim that being in pain has something to do with me saying "I am in pain" — Michael

But then, applying that to the snooker balls, you're averse to saying that seeing the ball as red has something to do with associating it with red surfaces generally? For example by reaching for the word "red". I thought you might be. Slightly surprised that you reply with "sure".

If you're not totally averse to that, though, how about that being in pain is associating the bodily trauma in question with bodily trauma in general? For example by reaching for the word "pain".

But then, applying that to the snooker balls, you're averse to saying that seeing the ball as red has something to do with associating it with red surfaces generally? For example by reaching for the word "red". I thought you might be. Slightly surprised that you reply with "sure".

If you're not totally averse to that, though, how about that being in pain is associating the bodily trauma in question with bodily trauma in general? For example by reaching for the word "pain". — bongo fury

I don’t need a language to be in pain. Pre-linguistic humans had headaches.

What I thought you were saying is that feeling pain can be reducible to brain states, and doesn’t require some non-physical supervenient phenomena. I’m not totally averse to that claim, although I’m not especially convinced by it either.

However, I think I'd call myself a realist, rightly, yet deny there even is a sub-stratum. — Moliere

Realism is defined as the assertion of the existence of a reality independently of our thoughts or beliefs about it, so a Realist wouldn't deny that there is a sub-stratum.

I wouldn't reduce reality to either phenomenology or semantics (or science) — Moliere

The Phenomenological Direct Realist believes they directly perceive something existing in a mind-independent world even if they don't know its name. The Semantic Direct Realist believes they directly perceive an apple existing in a mind-independent world.

For the Direct Realist, the terms phenomenology and semantics distinguish important features of their view of reality.

That's because without access to the substrate there's no way to check our inferences, or a way to check if there is a relationship between the substrate and the surface. We could only check it against the surface. It may match the substrate, but we'd never know due to its indirectness. — Moliere

That's true, but I have an innate belief in the law of causation, in that I know that the things I perceive in my mind through my senses have been caused by things existing outside my mind in a mind-independent world.

My belief in the law of causation is not based on reason, but has been been built into the structure of my brain through 3.5 billion years of life's evolution within the world.

I have no choice in not believing in the law of causation as I have in not believing I feel pain or see the colour red.

I don’t need a language to be in pain. Pre-linguistic humans had headaches. — Michael

They suffered the trauma. My car suffers trauma. And pain, but only metaphorically. They, though, probably also had enough symbolic ability to associate it with trauma in general. Which is how we suffer pain literally. Perhaps. Plausibly.

They suffered the trauma. My car suffers trauma. And pain, but only metaphorically. They, though, probably also had enough symbolic ability to associate it with trauma in general. Which is how we suffer pain literally. Perhaps. — bongo fury

We (usually) feel pain in response to trauma. They are two separate things.

The person with congenital insensitivity to pain can recognise the trauma of a broken leg without feeling any pain.

The rest of us can feel pain without recognising any trauma, e.g in the case of headaches or some internal injury (and there can be internal injuries that don’t cause pain too).

Pain and trauma just aren’t the same.

We don’t just associate pain with trauma; we feel pain in response to trauma. They are two separate things. — Michael

I'm suggesting the pain is the recognition of the trauma as an instance of a kind of thing, e.g. of trauma. It is the association. Sure it's separate from the trauma. It might be caused by the trauma. But not from or by the pain. It is the pain.

I'm suggesting the pain is the recognition of the trauma — bongo fury

And yet as I said we can recognise trauma without feeling pain (e.g. congenital insensitivity to pain) and we can feel pain without recognising trauma (e.g. headaches).

Hmm so you were distinguishing neural alarm from bodily trauma?

Hmm so you were distinguishing neural alarm from bodily trauma? — bongo fury

Yes. The broken leg is the trauma. The brain activity (or the mental phenomena it causes) is the pain.

Theories need to fit the facts, not the other way around, and it is a fact that the pain I feel isn't a property of the fire that causes me to feel pain.

So either there is a survival advantage to feeling pain, or feeling pain just happens to be a deterministic effect of something else that gives us a survival advantage (e.g. a complex brain that is able to effectively respond to stimulation). — Michael

Exactly. so what is the equivalent situation with 'seeing red' to which you want to extend this physiological response?

Your argument so far seems to be that because pain is a physiological state, then so can 'red' be. But that's woefully inadequate as a theory. By that same token, so can the number 7, or Donald Duck, or the solar system around alpha centuri. You have to have something more than just "because one thing is X other things can be X too, therefore P=X".

I'm asking what meta-framework (or evolutionary benefit, if you're working within the same framework as me) justifies your belief that 'seeing red' is the same type of thing as 'feeling pain' - it's not sufficient that it merely can be on the grounds that some things are.

The feeling of 'pain' serves a purpose related to the cause of the pain. You 'feel' the fist (in the first sense) so that you know where it is, how fast it's moving etc. You 'feel' pain (in the second sense) so that you avoid such situations in future.

What I'm asking is the equivalent in your model.

I'd say you 'see' red in the only sense I understand of the word 'see', that is you make some prediction of the state of some external data node (that it is 'red'). You do this so that you can respond to it appropriately (say, eat it because it's ripe). for this to work, 'red' has to be a property of that data node, if if's not then it can carry no information from it, and so your response is disconnected.

You want to say that 'red' is a feeling in this second sense, as description of the state of you mind, not the external node. So why? The 'feeling' of pain (second sense) sets us up to avoid the cause. What does the 'feeling' of red do?

or evolutionary benefit, if you're working within the same framework as me) — Isaac

Organisms may have features that have no evolutionary benefit.

Exactly. so what is the equivalent situation with 'seeing red' to which you want to extend this physiological response?

Your argument so far seems to be that because pain is a physiological state, then so can 'red' be. But that's woefully inadequate as a theory. — Isaac

It’s not woefully inadequate. It explains colour blindness and synesthesia and why some people see the dress to be white and gold and others black and blue and why science doesn't describe the world as having “particles of redness” and is exactly what the experiment I referenced days ago concluded.

There is a physiological sense of seeing red, and it is that which immediately informs our cognition and drives our responses (e.g. how we describe things). This physiological sense is (usually) triggered by electromagnetic radiation stimulating the sense receptors in our eyes, and the nature of that radiation is determined by the arrangement of the electrons that make up the surface of some external object.

This is what the empirical evidence shows. Your armchair theory and word games don't trump empirical evidence.

Realism is defined as the assertion of the existence of a reality independently of our thoughts or beliefs about it, so a Realist wouldn't deny that there is a sub-stratum. — RussellA

If Realism is the thesis that there is a sub-stratum then I'd fit anti-realist.

Just not sure what to make of the belief that the tree exists whether it's in a mind or not, given the previous notion of mind-independence. The moon spins. People feel. Perspectives fit within the surface, just as minds do, just as moons do.

I think people would be tempted to call the surface something like "experience", but I would do no such thing. "Experience" used like this is a reification. This notion of reality is that it is irreducible, and absurd -- to call it a substrate is to give it too much meaning, because there's no base.

The Phenomenological Direct Realist believes they directly perceive something existing in a mind-independent world even if they don't know its name. The Semantic Direct Realist believes they directly perceive an apple existing in a mind-independent world.

For the Direct Realist, the terms phenomenology and semantics distinguish important features of their view of reality. — RussellA

It still feels like a set-up to me. Wouldn't the direct realist have to be committed to the notion that our phenomenology is part of the world, just as semantics are? "Mind-independent" is doing a lot of work in distinguishing the direct from the indirect realist.

Let's just say the surface is mind-independent. Minds, whatever that happens to be, are within the surface, but do not define the surface. And, there's no substrate.

So by the set-up I'd be an anti-realist Direct realist :D -- maybe not so bad.

That's true, but I have an innate belief in the law of causation, in that I know that the things I perceive in my mind through my senses have been caused by things existing outside my mind in a mind-independent world.

My belief in the law of causation is not based on reason, but has been been built into the structure of my brain through 3.5 billion years of life's evolution within the world.

I have no choice in not believing in the law of causation as I have in not believing I feel pain or see the colour red. — RussellA

I don't know.

I think "causation" is one of those habits which we learn from those around us who teach us how to use it. It's different from what we feel, i.e. red or pain. We infer causation, and there are many ways of inferring causation. I'd say I am more on the side of Hume in saying that it's a habit of thought, but I wouldn't go so far as to specify it as a necessary connection between events. I think it's a much looser concept than that, as we can see the various notions of cause put forward by philosophers: Aristotle's four-causes, Hume's necessary connection, and Kant's tri-partite division into three distinct categories where the third is a synthesis of the previous two -- these conceptions of cause are not the same. Philosophers, at least in specifying this habit, are able to make distinctions between ways of thinking about causation, which gives me a reason to doubt that it's some innate idea: some of us have been able to pick it apart and then found different things. So it's more likely that we're inventing causation than it's innate, given the evidence of the intelligent and creative.

But even if causation isn't real, the trees deep in the Amazon live on without my mental blessing. Is that mind-independent?

or evolutionary benefit, if you're working within the same framework as me) — Isaac


Organisms may have features that have no evolutionary benefit. — frank

I explained that. Thinking is one of the most calorie intensive actions we do. The brain is a very expensive organ. There are no examples in the natural world of traits evolved which are calorie intensive (or otherwise costly) which nonetheless survive in the face of competition.

If you are arguing that features can be costly and still evolve, and that evolved features have no correlation to survival (or sexual selection), then you are literally arguing against the theory of evolution by natural selection. Which is why I asked @Michael for the alternative frame he might be using.

It explains colour blindness and synesthesia and why some people see the dress to be white and gold and others black and blue and why science describes the world as electrons absorbing or reflecting electromagnetic radiation of certain wavelengths rather than “particles of redness” and is exactly what the experiment I referenced days ago concluded. — Michael

So does the standard model, but without these holes. I'm asking why you choose the model with the holes (or why they are not, for you, holes at all). Why choose a model which creates this difficult to explain phenomena contrary to what we already have regarding evolved characteristics, when there appears to be no call for it?

So does the standard model, but without these holes. I'm asking why you choose the model with the holes (or why they are not, for you, holes at all). Why choose a model which creates this difficult to explain phenomena contrary to what we already have regarding evolved characteristics, when there appears to be no call for it? — Isaac

You just admitted to an internal, physiological sense of feeling pain. Why is it so difficult for you to extend this to other things, e.g. seeing colour?

You just seem so bewitched by the complexities of vision that you think it fundamentally different to other senses, like nociception. It isn't. It's just a different mode of experience caused by a different type of stimulus. When nociceptors are stimulated in certain ways, it triggers brain activity that causes the internal, physiological sense of feeling pain. When thermoreceptors are stimulated in certain ways, it triggers brain activity that causes the internal, physiological sense of feeling cold. When chemoreceptors are stimulated in certain ways, it triggers brain activity that causes the internal, physiological sense of tasting sweetness. When photoreceptors are stimulated in certain ways, it triggers brain activity that causes the internal, physiological sense of seeing red.

This is consistent with all the empirical evidence and explains why different people experience different things in response to the same external stimulus (slight differences with the central nervous system mean slight differences with the subsequent internal, physiological experience).

Purpose.

Are you deliberately ignoring this entire line of argument for a reason? All traits which carry significant cost (calorie or otherwise) demonstrate fairly well understood survival purposes (or other forms of selection).

You've not given any account of why you dismiss this meta-theory, or why you think 'feeling red' falls within it.

Outside of such an explanation, you theory explains empirical evidence no better than the standard one, but with this additional gap.