Poll about realism

[.13.]

P1: The BIV is immediately aware of something that looks like external physical object X.

P2: No X is actually present.

P3: They must therefore be aware must be something other than an external physical object X.

P4. But there is no qualitative or phenomenal difference between the objects of awareness in cases of hallucination and or perception.

P5: Given this indistinguishability, we should conclude that since the objects of immediate awareness in hallucination are not external physical objects, the objects of immediate awareness in veridical perception aren’t physical objects either.

Conclusion: Direct Realism is false. The objects of immediate awareness in hallucination and in veridical perception are something other than external physical objects. They are sense-data, ideas, etc….

Let's say I accept P1-P4. Are you saying that I can't have hallucinations AND experiences of external physical objects? Why does one exclude the other?

 

[UndercoverElephant]

Anyway, this is why I believe it is direct, after reading Wikipedia.

According to direct, the process of awareness of the external world is based on what is external, while in indirect, it is based on what is internal. They both sound good. However, by "external/internal", I will have to call for definition - I choose to say that the brain is the determining factor. If I am wrong in this, let me know.

I'm not really sure I understand what you mean in the 3rd sentence.

If I see a tree, I am not seeing it with my brain; I am seeing it with my eyes.

That suggests you could percieve a tree even if you didn't have a brain! I have not heard this suggestion before.

But I think I get what you mean....

If I touch the tree, I am not feeling it with my brain; I am feeling it with my skin. If I smell... you get the idea. All of that happens externally. All my brain does is process the information that is gathered externally in a way that "I" can rationalize. If I am seeing the color red, it is because my eyes have created that color and sent that image to my brain.

What is "I" here, and why put it in quotes?

In your hypothetical, the brain would not be a floating brain in its artificial world - it will need a body with sensory organs (all artificial) that will serve to 'send' the information to the brain. Therefore, since the actual gathering of information is external, it is a direct relationship.

So are you saying that the brain in the vat couldn't possibly have the same experiences (or the same brain state) unless it also had a body as well? If so, I agree with you. My own position is to deny P4, based upon an argument from QM. The basic point is that I do not accept it is possible to create the precise same brain state in a BIV as in a normal situation, and therefore the experience would differ and the BIV would not be fooled.

 

[UndercoverElephant]

One other point: It has been experimentally demonstrated (in a few different ways) that conscious awareness lags a couple of hundred milliseconds behind what the rest of the brain is actually doing. What's more, conscious awareness of conscious decisions actually lags behind the initiation of the action.

So if you want to put the cut-off between the event and where significant information processing occurs, we do not experience anything directly.

This is a version of yet another argument against direct realism, called the time-lag argument. It fails because you can argue that even though we aren't directly aware of objects as they currently are, we can still be directly aware of objects as they once were. But it is not the same as the argument from hallucination.

 

[PixyMisa]

This is a version of yet another argument against direct realism, called the time-lag argument. It fails because you can argue that even though we aren't directly aware of objects as they currently are, we can still be directly aware of objects as they once were.

But it's also an argument against indirect realism. As you said, indirect realism says that:

We are directly aware of sense-data/qualia/mental-impressions.

Which is apparently not true, or only true by arbitrarily defining "direct".

But it is not the same as the argument from hallucination.

No, it isn't.

 

[Lord Muck oGentry]

This is a poll about people's position on the question of realism with respect to physical objects.

Direct Realism:

The objects of perception during veridical experiences (i.e. not hallucinations or lucid dreams) are real physical objects which exist totally independently of mind(s).

Indirect/representational Realism:

We are not directly aware of physical object, but we are indirectly aware of them. We are directly aware of sense-data/qualia/mental-impressions....

Anti-realism:

We are not directly aware of mind-independent physical objects. This position includes idealism, transcendental idealism (Kant) and various other theories which deny we can be directly aware of physical objects which can exist independently of mind.

----------------------------------------

Direct realism is challenged by various sorts of arguments, but this one is the strongest, IMO.

The Argument from hallucination against direct realism:

“Hallucination” refers here to an experience which is phenomenologically indistinguishable from the veridical perception of an object, but which concerns no object at all which actually exists, such as in the case of a Brain In a Vat. It does not apply to people who have taken drugs, because in this case there is a different brain state implied and therefore a different experience expected. The argument assumes that it is possible to induce a "perfect hallucination" in a BIV.

The Argument runs as follows:

P1: The BIV is immediately aware of something that looks like external physical object X.

P2: No X is actually present.

P3: They must therefore be aware must be something other than an external physical object X.

P4. But there is no qualitative or phenomenal difference between the objects of awareness in cases of hallucination and or perception.

P5: Given this indistinguishability, we should conclude that since the objects of immediate awareness in hallucination are not external physical objects, the objects of immediate awareness in veridical perception aren’t physical objects either.

Conclusion: Direct Realism is false. The objects of immediate awareness in hallucination and in veridical perception are something other than external physical objects. They are sense-data, ideas, etc….

Just Geoff,

If P4 means anything at all (which I doubt), it is just plain wrong. When I think I see pink elephants, I don't 'phone the Zoological Society. I put the cork back in the Highland Park.

P1 to P5 is just a muddle. I have occasionally mistaken the sound of cats mating for the sound of a baby crying. But there is no need to bring in the notion of sense data to account for what I am immediately aware of ( if you care to put it that way). What I hear is the sound of cats mating, and if there is anything that I am "aware of ", it is the sound that they make: I just can't identify it correctly.

But the real mischief in this type of philosophical argufying is the way in which pseudotechnical terms are brought in without introduction. The phrase " immediately aware of" is not one that we use in humdrum talk to distinguish one way of seeing, touching or hearing from another. We do not say, for example, that we are "immediately aware of" large type but only "mediately aware of" the small print that forces us to put on our reading glasses. Or that we "mediately hear" what has to be relayed through the loudspeaker. Such terms need defining. If you can come up with a definition that does not leave us lamenting that seeing with our eyes or hearing with our ears is a poor second best to some sort of "immediate awareness", blessings on you!

Regards

 

[PixyMisa]

So you are saying that the BIV is aware of the data coming down its optic nerve, not physical objects.

Nope. The data coming down the optic nerve represents physical objects. The physicality of the objects is artificial, but that is irrelevant.

In this case it would be indirectly aware of non-existent objects and directly aware of something equating to sense data.

No. The objects really exist, in the world of experience of the brain in the vat. They don't exist outside that world, but it is impossible to construct any argument from that fact that relates to the way the brain in the vat experiences things. Our entire universe could be a simulation; that doesn't make any difference either.

This begs the question: why don't you then also say that during veridical experiences we are aware of sense data?

Because we aren't. When we see a tree, we see a tree. We don't experience photons or firings of the rods and cones or pulse-signals down the optic nerve. We see a tree, because our brains are constructed to do that.

And I can't "also" say that because I didn't say that at all.

What is the difference from the point of view of the brain?

None at all. Zip. Zero. Zilch. By definition.

Surely there is just one case of experiencing a world of fake sense data and one is experiencing a world of veridical sense data.

No. They are identical. Both are experiencing a real world. The definitions of real might vary - but it is impossible to determine that from inside the world, so it doesn't make any difference.

If so, then this position would have to be indirect realism.

No. It has no bearing on the question at all. The brain-in-vat scenario is identical for these purposes with hard materialism.

Please clarify what you think the brain in the vat experiences, directly and indirectly, and what the normal brain experiences, directly and indirectly, because I'm not sure what your position is.

Brains don't experience anything. They process information. But the two brains are processing information in exactly the same way. And because the two situations are identical from that perspective, the brain-in-vat argument can say nothing at all about whether direct or indirect realism is correct.

Edited for sleping.

 

[cpolk]

I'm not really sure I understand what you mean in the 3rd sentence.

I meant, if the process happens in the body, but not in the brain, is it external or internal?

That suggests you could percieve a tree even if you didn't have a brain! I have not heard this suggestion before.

The image created by my eye is independent of the brain. The eye creates the image, and sends the signal to the brain. If the eye is somehow activated, by whatever means, it will create the same images, regardless of whether or not it is connected to the brain.

So, my eye is what sees the tree, in any case.

What is "I" here, and why put it in quotes?

This "I" represents not the total functionailty of what the brain handles (blood flow, heart rate, digestion, reception of senses, etc.), but the secondary function of the brain that interacts with the external world.

So are you saying that the brain in the vat couldn't possibly have the same experiences (or the same brain state) unless it also had a body as well? If so, I agree with you. My own position is to deny P4, based upon an argument from QM. The basic point is that I do not accept it is possible to create the precise same brain state in a BIV as in a normal situation, and therefore the experience would differ and the BIV would not be fooled.

It may be possible, but imagine what would have to happen, first. We would have to create a machine that is capable of reproducing the environment from the human perspective. The only way to do that would be if the computer was capable of processing information from the human perspective itself. If the hypothetical computer of the futre is able to do that, then why do we need the brain in the vat?

 

[UndercoverElephant]

PM

Originally Posted by JustGeoff :

I don't understand this response. Surely we must be directly aware of something!?

Why? Consciousness is a physical process.

I can't make any sense of claims like "Consciousness is a physical process", which is why we are not discussion physicalism, materialism, dualism, mentalism/phenomenalism. "Consciousness is a physical process" is just a bald assertion of eliminative materialism. If you want to add a premise to the argument which says "eliminative materialism is true" then its a pointless argument, because the vast number of people who aren't eliminative materialists won't accept the premises and it ceases to be an interesting or relevant argument. Try to forget about the materialism/dualism/phenomenalism debate for the moment and concentrate on the claim about direct realism, indirect realism and non-realism.

Basically, if you start making making metaphysical assertions (of ANY sort), prior to analysing the argument, then you aren't analysing the argument at all. You are just feeding a conclusion into the argument, in this case a conclusion that is only indirectly related to the argument because the argument is NOT about physicalism.

This should not be a re-run of debates about materialism that have been done to death on this forum. It is specifically about realism and anti-realism which is NOT the same thing.

It is only aware of itself through physical processes. If that means that awareness of external objects is indirect, it means that self-awareness is also indirect.

Again, not sure what this means. You appear to be arguing that we are never directly aware of anything at all. This position looks prima facie absurd to me. In order to be indirectly aware of a physical world, we must be directly aware of something which isn't a physical world. If we were directly aware of nothing at all, then how could we possibly be indirectly aware of anything??

My point is that naturalism makes any distinction between direct and indirect realism arbitrary.

There is always a physical causal chain between the event and the experience of the event, even when the event is an internalisation of an external event.

We are NOT arguing about naturalism. The argument from hallucination is NOT an argument against naturalism and NOT an argument against physicalism. It is an argument against direct realism!

Nobody is contesting the claim that there is a physical causal chain between an event in the physical world (e.g. a photon being given off from an object) and the internal representation of this event (e.g. subjectively percieving the object). Naturalism does not make any distinction between direct and indirect realism arbitrary. It just doesn't have anything whatsover to do with direct and indirect realism.

PM, if you want to argue about naturalism and materialism then go and have an argument with somebody about naturalism and materialism. This thread is about direct realism, indirect realism and non-realism with regard to the perception of physical objects. Everybody else participating in this thread seems to understand this.

You need to think about the argument as it's presented. Do you believe the objects of direct awareness during BIV-style "hallucinations" are the same as the objects of direct awareness during veridical experiences?

Yes.

So what are they, sense-data? Or physical objects and fake physical objects?

If it is the former then you are an indirect realist. If it is the latter then you are claiming that the BIV is aware of things which have no existence. And if you are claiming that BIV is aware of things which have no existence then what reason do you have to suppose that normal experiences are DIRECTLY of real physical objects? Remember, the BIV and the normal experiences are supposedly indistinguishable.

The BIV is experiencing a real world. It's that simple.

Unfortunately, this result shows why this is argument is a reductio ad absurdum. Trying to defend direct realism has led you to claim that the brain in the vat is experiencing a real world. Yet (almost) everybody agrees a priori that the BIV can't possibly be experiencing a real world, because the world it is experiencing is an artificial simulation! That's the whole point, PM. The BIV can't possibly be experiencing a real world. So perhaps it isn't quite as simple as you think it is.

There is no possible meaningful distinction. Edit: To the brain.

So it would seem to follow from a defence of direct realism. Except we know there actually is a distinction!

 

[UndercoverElephant]

Let's say I accept P1-P4. Are you saying that I can't have hallucinations AND experiences of external physical objects? Why does one exclude the other?

You can't have something which is both an experience of a real physical object and a hallucination at the same time. These things are defined is such a way as to make them mutually exclusive. If there is a real object then it is a perception. If it there is no real object then it is an hallucination. If there is a real object (say, a stick) which looks bent to you but is actually straight then it is an illusion, that is to say you are percieving a real object, you just made a mistake about exactly what you percieved. The hallucinator isn't percieving a real object at all, unless you want to claim it is incorrectly percieving the probe in its brain - a highly complex case of illusion. I think that argument fails because its an unshatterable illusion.

 

[UndercoverElephant]

But it's also an argument against indirect realism.

That is correct. The time-lag argument claims to challenge both forms of realism. Personally I think it fails in both cases.

 

[UndercoverElephant]

Just Geoff,

If P4 means anything at all (which I doubt), it is just plain wrong. When I think I see pink elephants, I don't 'phone the Zoological Society. I put the cork back in the Highland Park.

For about the seventh time, we are talking about brains in vats, NOT people who are drunk or have taken LSD.

P1 to P5 is just a muddle. I have occasionally mistaken the sound of cats mating for the sound of a baby crying. But there is no need to bring in the notion of sense data to account for what I am immediately aware of ( if you care to put it that way). What I hear is the sound of cats mating, and if there is anything that I am "aware of ", it is the sound that they make: I just can't identify it correctly.

The argument gets even more complicated if you start bringing in non-visual forms of perception. Also, this reply sounds like it is more about the argument from illusion than the argument from hallucination.

But the real mischief in this type of philosophical argufying is the way in which pseudotechnical terms are brought in without introduction. The phrase " immediately aware of" is not one that we use in humdrum talk to distinguish one way of seeing, touching or hearing from another.

In humdrum talk we are all direct realists. Although this version of direct realism is generally refered to as "naive realism".

We do not say, for example, that we are "immediately aware of" large type but only "mediately aware of" the small print that forces us to put on our reading glasses. Or that we "mediately hear" what has to be relayed through the loudspeaker. Such terms need defining. If you can come up with a definition that does not leave us lamenting that seeing with our eyes or hearing with our ears is a poor second best to some sort of "immediate awareness", blessings on you!

Do you see with your eyes? Don't you need a brain too?

 

[PixyMisa]

I can't make any sense of claims like "Consciousness is a physical process", which is why we are not discussion physicalism, materialism, dualism, mentalism/phenomenalism. "Consciousness is a physical process" is just a bald assertion of eliminative materialism. If you want to add a premise to the argument which says "eliminative materialism is true" then its a pointless argument, because the vast number of people who aren't eliminative materialists won't accept the premises and it ceases to be an interesting or relevant argument. Try to forget about the materialism/dualism/phenomenalism debate for the moment and concentrate on the claim about direct realism, indirect realism and non-realism.

No. You reject external events as being directly experienced because there is a chain of physical processes between the event and the experience. I have pointed out that the same thing happens inside the brain itself.

You can't argue meaningfully about how we perceive things when you ignore everything we know about how we perceive things.

Basically, if you start making making metaphysical assertions (of ANY sort), prior to analysing the argument, then you aren't analysing the argument at all. You are just feeding a conclusion into the argument, in this case a conclusion that is only indirectly related to the argument because the argument is NOT about physicalism.

I didn't.

Again, not sure what this means. You appear to be arguing that we are never directly aware of anything at all.

No. I am saying that the definition of "direct" is necessarily arbitrary.

This position looks prima facie absurd to me. In order to be indirectly aware of a physical world, we must be directly aware of something which isn't a physical world. If we were directly aware of nothing at all, then how could we possibly be indirectly aware of anything??

Awareness is fundamentally indirect. Your awareness of a thing is never the thing itself. Your awareness of your awareness is not the same as your awareness. Thus, the distinction is arbitrary, but if you assume that naturalism holds, then direct realism is the more appropriate and useful paradigm.

We are NOT arguing about naturalism. The argument from hallucination is NOT an argument against naturalism and NOT an argument against physicalism. It is an argument against direct realism!

Nope. It says nothing whatseover about direct realism. It can't. It merely susbtitutes one real world for another. That changes nothing.

Nobody is contesting the claim that there is a physical causal chain between an event in the physical world (e.g. a photon being given off from an object) and the internal representation of this event (e.g. subjectively percieving the object). Naturalism does not make any distinction between direct and indirect realism arbitrary. It just doesn't have anything whatsover to do with direct and indirect realism.

It has to do with the definition of "direct", something you have completely failed to come to grips with. What do you mean when you say "direct"?

PM, if you want to argue about naturalism and materialism then go and have an argument with somebody about naturalism and materialism. This thread is about direct realism, indirect realism and non-realism with regard to the perception of physical objects. Everybody else participating in this thread seems to understand this.

You brought up the brain in the vat argument. I have merely pointed out that it doesn't say anything at all, much less falsify direct realism.

So what are they, sense-data?

No.

Or physical objects and fake physical objects?

No.

They are, in both cases, real physical objects.

If it is the former then you are an indirect realist.

So I'm not an indirect realist.

If it is the latter then you are claiming that the BIV is aware of things which have no existence.

So I'm not claiming that either. Good.

And if you are claiming that BIV is aware of things which have no existence then what reason do you have to suppose that normal experiences are DIRECTLY of real physical objects?

Since I didn't claim that, that doesn't apply.

Remember, the BIV and the normal experiences are supposedly indistinguishable.

Exactly what I have been trying to explain to you all along.

They are indistinguishable. This "real" and "fake" is entirely false. They are, in both cases, physical objects.

Unfortunately, this result shows why this is argument is a reductio ad absurdum. Trying to defend direct realism has led you to claim that the brain in the vat is experiencing a real world.

This is necessarily true.

Yet (almost) everybody agrees a priori that the BIV can't possibly be experiencing a real world, because the world it is experiencing is an artificial simulation!

How does that make it any the less real? As I pointed out, repeatedly, our entire universe could be a simulation, and this changes absolutely nothing about the way we perceive it.

That's the whole point, PM. The BIV can't possibly be experiencing a real world.

Sorry, but that is simply nonsense. To the brain in the vat, the world it is experiencing is real, and so its experiences are of precisely the same nature as our experiences. To people outside the brain's artificial world, this is false, but that still says nothing about the nature of the brain's experiences in any terms relevant to the brain.

The argument is perfectly hollow.

So it would seem to follow from a defence of direct realism. Except we know there actually is a distinction!

Nope.

 

[PixyMisa]

That is correct. The time-lag argument claims to challenge both forms of realism. Personally I think it fails in both cases.

Fine.

The problem is, this is entirely arbitrary, and all other arguments against direct realism fail in the same way.

Now, you can posit an arbitrary-but-useful distinction and say that what happens inside the brain is direct and what happens outside the brain is indirect - but it is arbitrary.

 

[UndercoverElephant]

Nope. The data coming down the optic nerve represents physical objects. The physicality of the objects is artificial, but that is irrelevant.

It is highly relevant. "The physicality of the objects is artificial" means "indirect realism".

"In this case it would be indirectly aware of non-existent objects and directly aware of something equating to sense data."

No. The objects really exist, in the world of experience of the brain in the vat. They don't exist outside that world.....

This is precisely the sort of confusion that needs to be avoided. You are simultaneously claiming that the objects really exist and really don't exist. This is why direct realism is considered by many people to be very hard or impossible to defend. You can't have a wobbly definition of "real" in an argument about realism!

, but it is impossible to construct any argument from that fact that relates to the way the brain in the vat experiences things. Our entire universe could be a simulation; that doesn't make any difference either.

It makes a difference because it leads to the logical nightmare of claiming things are simultaneously real and not real!

This begs the question: why don't you then also say that during veridical experiences we are aware of sense data?

Because we aren't.

That's not an argument.

When we see a tree, we see a tree. We don't experience photons or firings of the rods and cones or pulse-signals down the optic nerve. We see a tree, because our brains are constructed to do that.

Not sure what this means or why it is relevant.

Surely there is just one case of experiencing a world of fake sense data and one is experiencing a world of veridical sense data.

No. They are identical. Both are experiencing a real world.

Eh?

The brain in the vat and the veridical perciever are both experiencing a real world??????

You don't think there is a difference between the world the vat percieves and the world that you percieve?????

Of course there is a difference, PM. One of them's real and the other isn't.

The definitions of real might vary.....

You cannot refute the argument from hallucination by defining "real" to mean something different at different point in the argument. To do so is a straightforward acceptance that the argument is valid. If the only way to defend direct realism involves a wobbly definition of "real" then the direct realism has been defeated.

Brains don't experience anything. They process information. But the two brains are processing information in exactly the same way. And because the two situations are identical from that perspective, the brain-in-vat argument can say nothing at all about whether direct or indirect realism is correct.

I think your own position is demonstrating that this is not the case. You need to find a defence against the argument which doesn't depend on an inconsistent definition of "real".

 

[UndercoverElephant]

I meant, if the process happens in the body, but not in the brain, is it external or internal?

Still not sure what you mean, but things happening exclusively within the body are internal to the body. Whether they are also internal to experience is another matter.

The image created by my eye is independent of the brain. The eye creates the image, and sends the signal to the brain. If the eye is somehow activated, by whatever means, it will create the same images, regardless of whether or not it is connected to the brain.

Yes, but would anything percieve those images? Do you think a disembodied eye can have experiences of objects?

So, my eye is what sees the tree, in any case.

Your eye is part of the causal chain that results in a perception of a tree.

It may be possible, but imagine what would have to happen, first. We would have to create a machine that is capable of reproducing the environment from the human perspective. The only way to do that would be if the computer was capable of processing information from the human perspective itself.

Surely the computer would just need to know exactly how the optic nerve encodes visual images? Why would it need to know how this data becomes an experience? The brain does that bit.

If the hypothetical computer of the futre is able to do that, then why do we need the brain in the vat?

Not sure what you mean......

 

[PixyMisa]

It is highly relevant. "The physicality of the objects is artificial" means "indirect realism".

Nope. Doesn't work.

The physicality of the objects is only artificial by reference to another universe. You don't get to do that.

The brain in the vat and the veridical perciever are both experiencing a real world??????

Precisely.

You don't think there is a difference between the world the vat percieves and the world that you percieve?????

None whatsoever.

Of course there is a difference. PM. One of them's real and the other isn't.

The point is, once again, that the brain in the vat cannot tell that its world is anything but real - by definition - so you cannot argue that its perceptions differ in any way from those of brains in our world.

Furthermore, it is impossible for you to know that our universe is what you call "real". So the argument fails again.

You cannot refute the argument from hallucination by defining "real" to mean something different at different point in the argument.

I'm not the one redefining "real". You are. "Real" only makes sense within a universe. The brain in the vat is experiencing a causally closed universe of its own. You cannot make any logical argument regarding its experiences by stepping outside that universe.

I think your own position is demonstrating that this is not the case. You need to find a defence against the argument which doesn't depend on an inconsistent definition of "real".

No; that's your problem.

 

[UndercoverElephant]

Fine.

The problem is, this is entirely arbitrary, and all other arguments against direct realism fail in the same way.

Not if they force you to define "real" inconsistently, PM.

 

[cpolk]

The brain in the vat and the veridical perciever are both experiencing a real world??????

Unless the brain in the vat knows that it is a brain in a vat, yes. The program run by the computer, in every respect of the term, is the brain's reality.

 

[PixyMisa]

Not if they force you to define "real" inconsistently, PM.

See above.

 

[UndercoverElephant]

The point is, once again, that the brain in the vat cannot tell that its world is anything but real - by definition - so you cannot argue that its perceptions differ in any way from those of brains in our world.

I'm not. Personally, I argue you can't artificially induce a veridical brain state. The point is that even though the brain can't tell the difference, we still know there is a difference.

I'm not the one redefining "real". You are.

Sorry, PixyMisa, but I haven't defined "real" at all. You have, and you defined it as follows:

Both are experiencing a real world. The definitions of real might vary - but it is impossible to determine that from inside the world, so it doesn't make any difference.

If you need to "vary the definition" of "real", then you can't claim to have defeated the argument. If you don't understand this then there is no point in continuing this discussion. It's like someone saying "1=0, but also 1=1. See. No problem".