Is it possible to perceive a world which is external to our perceptions?

[Tricky]

1) Objects exist independant of our perception.
2) These objects have an extremely large number of characteristics some of which the subjective viewer may only detect if he looks extremely closely (such as the spin of individual electrons).
3) It is impossible for any subjective viewer(s) to determine every characteristic of any given object, but given a great deal of effort, we may be able to describe them in a way that would be recognizable to almost any other subjective viewer.

 

[UndercoverElephant]

1) Objects exist independant of our perception.

That's yes to statement 2.

2) These objects have an extremely large number of characteristics some of which the subjective viewer may only detect if he looks extremely closely (such as the spin of individual electrons).

This doesn't make any claims about the statements.

3) It is impossible for any subjective viewer(s) to determine every characteristic of any given object, but given a great deal of effort, we may be able to describe them in a way that would be recognizable to almost any other subjective viewer.

Neither does this.

[size=-2]
1) We percieve objects (tables, chairs, etc....). We will call these "the objects of perception"

2) There is a world, external to humans (it existed before we evolved, it exists when we aren't looking), which is made of things like tables and chairs.

3) Presumably, the tables and chairs we perceive and the tables and chairs in the external world are the same tables and chairs.

Currently declared:

Upchurch: Yes, Yes, No
Sir-Drinks-alot: Yes, Yes, Yes
chriswl: No, ?, ?
Paul: ?, Yes, ?
Mercutio: ?, No, -
Tricky: ?, Yes, ?

[/size]

 

[Soapy Sam]

Is there a law that says every philosophical discussion, even if its not actually about materialism, must start with an assumption that materialism is true?

Whose law is that?

Yes.

It's one of Wilde's.

 

[Paul C. Anagnostopoulos]

What do I know? I just want to find out if an object of perception is the external object or my subjective image of it.

~~ Paul

 

[Paul C. Anagnostopoulos]

You might like this:

http://claytonlittlejohn.blogspot.co...-ive-been.html

Incomprehensible. That guy can't write his way out of a paper bag.

~~ Paul

 

[Mercutio]

Is there a law that says every philosophical discussion, even if its not actually about materialism, must start with an assumption that materialism is true?

Wow...According to Soapy Sam, I am violating a law! Cool...

SS, is that "every philosophical...", or merely the ontological discussions? Do you have a source (I'm happy to search for myself, I ask only to save time) for this law and the context in which it is given?

M

 

[ARubberChickenWithAPulley]

1) We percieve objects (tables, chairs, etc....). We will call these "the objects of perception"

Okay.

2) There is a world, external to humans (it existed before we evolved, it exists when we aren't looking), which is made of things like tables and chairs.

Still following.

3) Presumably, the tables and chairs we perceive and the tables and chairs in the external world are the same tables and chairs.

Presumably.

What's the question?

 

[Elind]

If you try to answer yes to both questions then you are saying we can percieve a world which is independent of our perceptions of it. But if it is independent of our perceptions of it how could we possibly have perceptions of it? Anyone got any suggestions?

Semantics problem. I think you are assigning the wrong meaning to the ability to perceive and confusing that with solipsism.

 

[roger]

I quite deliberately haven't mentioned materialism.

Whaaa????

Your opening post. You asked two questions to materialists. Specifically you wrote "Q1 for materialists", and "Q2 for materialists". So yes, if that's how you start, if you want to figure out what materialists say about a situation, and the consequences of what they say, you have to remain within materialist assumptions. Is this not clear, or did you misword your opening post?

You had a bunch of other questions about where the implied dualism is in your questions and terms. It's clear when you start responding to people. You talk about "objects of perceptions" and then mix all up whether you are talking about some thing out there, the particles bouncing off that thing, or the coded representation that our brain produces. And that's why we say we have no idea what you are talking about when you say the object of perception. Because then you ask weird questions if the object is "directly perceived". If it is in our brain. etc. Just weird stuff that clearly does not accept the idea of a collection of particles impigning on each other.


The semantics of the term isn't even clear. Are you saying "objects...which we perceive" or the things that make up the perception itself? Entirely different things. Or are you talking about the process of recognition, of organizing patterns in brains, etc.? I just can't tell. Break it down reductively, and tell us what you mean by your statements. Unambiguously. I did it (I assert) with my particles. You may not agree with the model, but there is no confusion as to how things work, what plays what role, where errors can creep in and how to detect and correct those errors.

 

[JayT]

Logic Is A Two-Edged Sword

Is it possible to perceive a world which is external to our perceptions?

Actually, Earthborn has a valid point.

Asking: "Is it possible to perceive a world which is external to our perceptions?"
is essentially the same thing as asking "Can we detect something that is undetectable?"

Something beyond our perceptions cannot be perceived by definition.

So the question is logically invalid, since we cannot possibly proceed to answer a question given in that form because it makes no logical sense.

I think I understand the answer you're seeking, but that's not the correct way to ask the question.

Unfortunately, the logical answer to the projected assumption is 'NO'.

The reason is because if we can perceive a 'thing', then by definition that 'thing' IS within our perceptions or we would have no actual knowledge of it whatsoever and its existence would be pure belief or speculation without any tangible foundations upon which to rest.

We can only call what we perceive 'knowledge' if it has at least one kernel of substantial, perceptible fact at its core. The difference between superstition and knowledge is the existence of this factual core as a foundation.

Simply put, we can't know anything that we can't perceive or is beyond our perceptions. Think very carefully about it.

All the knowledge that we have is perceptible, but not all the knowledge that exists is within our perceptions.

That doesn't prove that the world you seek to explore doesn't exist, but it does mean that if it exists, you have no way of knowing - without delving into supernatural beliefs - and please let's not go there, you're too bright for that, thus logically invalidating the question.

You ask a forever unanswerable question.

In computer logic terms, the question is an infinite loop, and in this case, an irresolvable question means the same as 'NO'

I'm sticking explicitly to the parameters of the question and making minimal external assumptions, so it may not be the answer you are seeking if we are on different pages of abstract thought.

 

[Earthborn]

1) We percieve objects (tables, chairs, etc....).

Obviously.

We will call these "the objects of perception"

If you insist.

2) There is a world, external to humans (it existed before we evolved, it exists when we aren't looking), which is made of things like tables and chairs.

Tables and chairs are not objects that have existed before perceiving humans evolved, so I can't agree to this. Tables and chairs were created by perceiving humans, showing that the physical world is influenced by us just like we are influenced by the physical world.

Even with a materialistic definition of "mind", this would still be true, since there are no tables and chairs inside our skulls.

I disagree. The only reason they are tables and chairs is because of our mental concept of them. Without that, they would just be shapes of wood or whatever they are made of. They are only tables and chairs because we perceive them as tables and chairs and use them accordingly.

3) Presumably, the tables and chairs we perceive and the tables and chairs in the external world are the same tables and chairs.

I don't think that's true either. Our perception of a thing is never identical to the thing itself. I don't even think it is meaningful to claim that they are the same, because that appears to suggest that they somehow appear to be two different objects. But in reality there is just the object and seeing it triggers associations in the brain.

 

[UndercoverElephant]

Where this thread is going to go

Hi All

OK, I need to answer some previous posts, but here's where this thread is headed. So far only two people were happy to answer (yes,yes,yes) - sir-drinks-alot and rubberchicken. This may partly be because clarification is needed on my part and I'll do my best later today. The thread is about the possibility of defending (yes,yes,yes) as an answer set, given the example of the hallucinating brain-in-a-vat.

The thread is about the possibility of defending Direct Realism, which is a theory of perception. This shouldn't be confused with materialism (although there may be implications in that area).

Direct realism is the following claim:

http://en.wikipedia.org/wiki/Direct_realism

Direct realism is the view that the immediate (direct) objects of perception are external objects, qualities, and events.

Do not confuse direct realism with the more naïve view discussed earlier, that the world is exactly as we perceive it to be. Obviously, sometimes we misperceive the world. The direct realist does not deny that there are perceptual illusions. The claim is, rather, simply that when we do perceive something, what we directly perceive, the immediate object of perception, is in the external world, not in the mind.

The problem is this:

The brain in the vat (BIV) seems to be aware of objects also. But the objects the BIV is aware of are not real objects - they only exist as simulations in a computer. Surely, then, the BIV is only directly aware of representations of objects rather than the real objects of an external world. Yet the BIV is having experiences no different to normal ones - so surely it also follows that during normal perception we are also only aware of what might be called "representational objects" or "image data". If this is the case, then it seems that direct realism must be false and either indirect realism or anti-realism (with respect to external objects) must be true.

Direct realism : The claim we can directly percieve external objects.

Indirect realism : The claim we only indirectly percieve external objects, and that what we directly percieve is something like "sense data" or "mental images".

Anti-realism : We don't percieve an external world at all (not the same as saying there isn't one).

At the bottom of the wikipedia entry on direct realism is the following note about "mental images":

The topic of mental images is very complicated and controversial.

One considered view is similar to Reid's. It is that, in some sense, we do indeed have images of various sorts in our minds when we perceive, and dream, and hallucinate, and use our imaginations, but when we actually perceive things, our sensory images, or sensations, if you will (that's Reid's word), cannot be considered the objects of perception, or attention, in any sense whatsoever. The only objects of perception are external objects. Even if perception is accompanied by images, or sensations, it's wrong to say we perceive sensations.

This conclusion shows that direct realism simply defines perception as perception of external objects where an 'external object' is allowed to be a photon in the eye but not an impulse in a nerve leading from the eye. Recent work in neuroscience suggests a shared ontology for perception, imagination and dreaming, with similar areas of brain being used for all of these. As le Morvan (2004) points out, such a shared ontology is fatal for direct realism.

If we get that far, I have an original defence of direct realism which is a partly taken from the answer provided by A.D.Smith's 2003 book "The problem of perception" (as I understand it) and partly draws on Penrose's theory of consciousness. But that is for later. Smith's book offers much of the answer but leaves at least one important question unanswered. I think Penrose may have provided a way to answer that important question.

Here's a detailed review of Smith's book, should anyone be interested.

http://www.people.fas.harvard.edu/~ssiegel/papers/DRPC.htm

I'll be back in a couple of hours. I have a metaphysics class to get to.

Geoff

 

[Paul C. Anagnostopoulos]

The brain in the vat (BIV) seems to be aware of objects also. But the objects the BIV is aware of are not real objects - they only exist as simulations in a computer. Surely, then, the BIV is only directly aware of representations of objects rather than the real objects of an external world. Yet the BIV is having experiences no different to normal ones - so surely it also follows that during normal perception we are also only aware of what might be called "representational objects" or "image data". If this is the case, then it seems that direct realism must be false and either indirect realism or anti-realism (with respect to external objects) must be true.

This would all go away if philosophers would just admit "Oh yeah, right, our internal images of things are based on sensory input from the world." Then the human/BIV distinction disappears.

Direct realism : The claim we can directly percieve external objects.

I still do not understand what it means to directly perceive something. Does it mean there is no homunculus?

Indirect realism : The claim we only indirectly percieve external objects, and that what we directly percieve is something like "sense data" or "mental images".

Here is where the definition of perceive becomes really murky. This clearly implies some sort of homunculus watching a movie in the brain.

How about:

Sensory realism : Through a process not yet completely understood, sensory information interacts with the brain to produce internal images of external objects. It is unknown whether there is a central homunculus involved.

~~ Paul

 

[Kevin_Lowe]

The problem is this:

The brain in the vat (BIV) seems to be aware of objects also. But the objects the BIV is aware of are not real objects - they only exist as simulations in a computer. Surely, then, the BIV is only directly aware of representations of objects rather than the real objects of an external world. Yet the BIV is having experiences no different to normal ones - so surely it also follows that during normal perception we are also only aware of what might be called "representational objects" or "image data". If this is the case, then it seems that direct realism must be false and either indirect realism or anti-realism (with respect to external objects) must be true.

I think you need to be careful here to distinguish between positions which claim 100% certainty and those which claim 99.99...% certainty about these things.

I don't think anyone post-Descarte has been able to sensibly claim that they are 100% certain that their sense data maps on to an external world. Orange skeptics probably claim to, but I think they're a bit overexited.

However as a matter of simple practicality, everybody acts as if there is a 99.99...% certainty that their sense data maps on to an external world that behaves in reliable ways whether or not anybody is watching.

Direct realism : The claim we can directly percieve external objects.

I think it's virtually certain we do a lot of the time, for any value of "directly perceive" which isn't silly. Obviously sometimes we dream and hallucinate too, or get fooled by optical illusions. So if the claim is that we can do so, and we aren't defining "directly perceive" to mean anything too silly, then this position as you describe it is one we treat as true.

Indirect realism : The claim we only indirectly percieve external objects, and that what we directly percieve is something like "sense data" or "mental images".

There are plenty of links in the chain of perception. You can say I don't directly perceive speech, just vibrations in the air, and that I don't directly perceive vibrations but rather the movement of hairs inside my ear, and I don't directly perceive that and so on. So if you call that being indirect, then all of our perceptions are very indirect indeed.

I don't think the distinction here between "direct" and "indirect" is any use as it is. You need to define in a lot more detail what you mean by direct and indirect. I suspect that if you want them to be contrasting definitions it is going to be very hard to define them both clearly without making one of them, at least, completely ridiculous.

Anti-realism : We don't percieve an external world at all (not the same as saying there isn't one).

I suspect any development of this idea will turn out to be unfalsifiable, and thus no use to man or beast.

 

[CFLarsen]

Just in case some of you are new to this Geoffesque thread, it is the same as the other Geoffesque thread.

~~ Paul

I agree. It's the same broken record.

 

[Paul C. Anagnostopoulos]

There are plenty of links in the chain of perception. You can say I don't directly perceive speech, just vibrations in the air, and that I don't directly perceive vibrations but rather the movement of hairs inside my ear, and I don't directly perceive that and so on. So if you call that being indirect, then all of our perceptions are very indirect indeed.

From what I can gather, indirect realism doesn't refer to the indirectness (stages) of the sensory perception process. Instead, it refers to a homunculus-like thing watching a movie played out on some kind of screen in the brain. The perception is indirect because it is of the movie, not the external world directly. Geoff?

Now we can take this two ways. One, we can say it's a matter of empirical investigation. Once we understand how the brain works, we'll know whether there is a central homunculus. Or, we can make a big metaphysical deal out of it and talk about the inherent dualism of the mind, ask who the homunculus is, suggest that homunculi might be connected (ESP?), and so forth.

~~ Paul

 

[UndercoverElephant]

Whaaa????

Your opening post. You asked two questions to materialists. Specifically you wrote "Q1 for materialists", and "Q2 for materialists".

OK, yes. I meant I hadn't made any claims about the truth-vlaue of materialism. Materialists tend to be either indirect or direct realists, but the latter position is a nightmare to defend. Traditional coginitive science is inevitably indirect realism because it's representational - it claims the brain creates a representation of the external world and that we are aware of the representation. This view is also problematic, but in very different ways to direct realism.

So yes, if that's how you start, if you want to figure out what materialists say about a situation, and the consequences of what they say, you have to remain within materialist assumptions. Is this not clear, or did you misword your opening post?

Because I didn't think properly before posting it.

You had a bunch of other questions about where the implied dualism is in your questions and terms. It's clear when you start responding to people. You talk about "objects of perceptions" and then mix all up whether you are talking about some thing out there, the particles bouncing off that thing, or the coded representation that our brain produces.

Brains are only a side-issue. I am interested in the nature of the objects of perception.

And that's why we say we have no idea what you are talking about when you say the object of perception. Because then you ask weird questions if the object is "directly perceived". If it is in our brain. etc. Just weird stuff that clearly does not accept the idea of a collection of particles impigning on each other.

It doesn't really say anything at all about particles. It is assumed there is an empirical causal chain between an external object and your brain.

The semantics of the term isn't even clear. Are you saying "objects...which we perceive" or the things that make up the perception itself? Entirely different things. Or are you talking about the process of recognition, of organizing patterns in brains, etc.? I just can't tell.

I am talking about the objects you perceive. I am talking about the keyboard that is sitting in front of you. Those objects. What are they? Are they same kind of thing for a brain-in-a-vat as for a normal person? If so, how can the normal person be perceiving real external objects?

 

[Kevin_Lowe]

From what I can gather, indirect realism doesn't refer to the indirectness (stages) of the sensory perception process. Instead, it refers to a homunculus-like thing watching a movie played out on some kind of screen in the brain. The perception is indirect because it is of the movie, not the external world directly. Geoff?

If so, the indirect position is going to have its work cut out trying to define which part of the sensory chain is the movie screen, which is the homonculus, and which is the light from the screen the homonculus is perceiving.

Now we can take this two ways. One, we can say it's a matter of empirical investigation. Once we understand how the brain works, we'll know whether there is a central homunculus. Or, we can make a big metaphysical deal out of it and talk about the inherent dualism of the mind, ask who the homunculus is, suggest that homunculi might be connected (ESP?), and so forth.

It's a safe bet Geoff is going to try to develop some dodgy proof of immaterialism out of this, but so far everyone has been admirably cautious and precise. I'm curious to see what his next move is going to be.

 

[Ichneumonwasp]

I still do not understand what it means to directly perceive something. Does it mean there is no homunculus?

No. There is a homonculus in both the simplistic direct and indirect forms of perception that Geoff is offering. In the direct form (which you cannot get to from the questions he asked without making furhter assumptions about how people interpreted what he meant) the homonculus directly perceives what is out there. The common objection is that you cannot hten account for illusions or hallucinations.

The real problem is that these simplistic ways of viewing perception are simply wrong. Perception is not a passive process, for one. The whole thing is an active attempt by a body to get useful info to navigate the world, so perception itself is intensional, full of beliefs (not completely constrained by them, but there are definite feed-forewqrd mechanisms at play), directed attention, etc. So don't fall for the hidden homonculi at the heart of the false dilemma you are being fed.

 

[UndercoverElephant]

Actually, Earthborn has a valid point.

Asking: "Is it possible to perceive a world which is external to our perceptions?"
is essentially the same thing as asking "Can we detect something that is undetectable?"

Something beyond our perceptions cannot be perceived by definition.

So the question is logically invalid, since we cannot possibly proceed to answer a question given in that form because it makes no logical sense.

You mean the question has to be answered "no". I agree.

I think I understand the answer you're seeking, but that's not the correct way to ask the question.

Unfortunately, the logical answer to the projected assumption is 'NO'.

The reason is because if we can perceive a 'thing', then by definition that 'thing' IS within our perceptions or we would have no actual knowledge of it whatsoever and its existence would be pure belief or speculation without any tangible foundations upon which to rest.

Right, so it seems that direct realism has to be false. Your position is therefore one of anti-realism with respect to external objects. We can never actually percieve the self-existing objects in the external world because they are independent of perception and we only know our perceptions.

We can only call what we perceive 'knowledge' if it has at least one kernel of substantial, perceptible fact at its core. The difference between superstition and knowledge is the existence of this factual core as a foundation.

Simply put, we can't know anything that we can't perceive or is beyond our perceptions. Think very carefully about it.

I agree. But there are implications that follow from this conclusion.

All the knowledge that we have is perceptible, but not all the knowledge that exists is within our perceptions.

That doesn't prove that the world you seek to explore doesn't exist, but it does mean that if it exists, you have no way of knowing - without delving into supernatural beliefs - and please let's not go there, you're too bright for that, thus logically invalidating the question.

I'm not interested in supernaturalism at this moment. This thread is a discussion of a technical point which kept coming up in the thread about science and materialism. I defined the objects of perception and the external objects to be different things, not to be confused. Some people initially accepted this claim but then later tried very hard to go back on it - and we spent countless pages trying to resolve the question of whether or not there was a fundamental difference between the two things. What the debate boiled down to was that most of the people in the thread wanted to defend direct realism - the claim that the objects of perception really are the external objects - but this turns out to be easier said than done. The brain in the vat is the biggest problem.