Brain-in-a-vat argument v. Our universe is a simulation

Speakpigeon

Valued Senior Member
There is a fundamental difference the Brain-in-a-vat argument and the idea that our entire world is a simulation running on a computer.

The Brain-in-a-vat seems within the reach of even human technology. In other words, it is a highly convincing and realistic scenario. A brain in a vat would presumably take the simulated physical world to be the actual world.

The idea of a simulation, that the world itself, including the brain experiencing this world, could be a simulation is much more fantastic and therefore somewhat more difficult to accept as a possibility.

The main sticking point, however, is that we still have no explanation as to how our subjective experience could possibly be a property or consequence of the way our brain works. The idea of a simulation requires that we accept the idea that our subjective experience would be a creation of the simulation and therefore, fundamentally, an illusion.

In the Brain-in-a-vat, the nature, or indeed natures, of both our brain and our subjective experience remain exactly as we believe them to be. With the idea of a simulation, both our subjective experience and the physical world are turned into illusions.

The Brain-in-a-vat, although more realistic and conceivable, is nonetheless more metaphorical in its motivation. It doesn't even try to suggest that you really are a brain in a vat. Rather, it is an argument, a logical argument to explain why we cannot be certain of the reality of our perception of the physical world and, hence, of the reality of the physical world itself as we think of it.

The idea of the simulation is not an argument. It is a metaphysical claim about reality. A such, it is to be seen as connected with the idea that consciousness is a process and, therefore, to the idea that computers can become conscious. All that would be required would be that the software got to a sort of critical threshold of complexity.

The Brain-in-a-vat, on the contrary, suggests a decisive epistemological dualism between our own mind that we know and that we therefore know that it exists (Descartes' "I think, therefore I am") and the material world that we can only believe in, and that therefore we don't know that this material world really exists.

In effect, these two ideas are polar opposite. The Brain-in-a-vat says the physical world may not exist, while the simulation says that our subjective experience may be just an illusion.

To the extent that they are polar opposite, I don't see how anyone could see these two ideas as equally convincing. If you find them equally convincing, it is likely because you haven't understood at least one of them.
EB
 
I've read this through three times; it's full of good stuff. First time I didn't quite get the distinction; second time I did; third time I second-guessed myself, and now I have some questions about the distinction.

It would be really interesting to engage in a discussion about it - I am fascinated by philosophical issues of self-identity - and I started to write out some responses.

Unfortunately, I know for a certainty that, at some point, SP will whip out a ruler and whack me on the knuckles for some perceived transgression. So, after several minutes of reflection, weighing the cost-benefit ratio, I've decided to pass. And that's sincerely a pity.
 
I've read this through three times; it's full of good stuff. First time I didn't quite get the distinction; second time I did; third time I second-guessed myself, and now I have some questions about the distinction.

It would be really interesting to engage in a discussion about it - I am fascinated by philosophical issues of self-identity - and I started to write out some responses.

Unfortunately, I know for a certainty that, at some point, SP will whip out a ruler and whack me on the knuckles for some perceived transgression. So, after several minutes of reflection, weighing the cost-benefit ratio, I've decided to pass. And that's sincerely a pity.
Tell you what, have a go anyway, and if he whips out a ruler then ignore him and continue with those who are willing to engage in what you have written?
 
There is a fundamental difference the Brain-in-a-vat argument and the idea that our entire world is a simulation running on a computer.

The Brain-in-a-vat seems within the reach of even human technology. In other words, it is a highly convincing and realistic scenario. A brain in a vat would presumably take the simulated physical world to be the actual world.

The idea of a simulation, that the world itself, including the brain experiencing this world, could be a simulation is much more fantastic and therefore somewhat more difficult to accept as a possibility.
For you, perhaps. Others have less difficulty than you seem to express. Others in fact not only accept it as a possibility but in fact accept it as the likeliest situation in which we find ourselves. Not that those people behave in any practical way particularly differently to those that don’t believe it.
The main sticking point, however, is that we still have no explanation as to how our subjective experience could possibly be a property or consequence of the way our brain works.
Why is that a sticking point? One simply needs to assume that it is, that there is no substance dualism involved, no soul, no religious stuff, and that it really is just a case of the workings of the brain. If one assumes that then it shouldn’t be too difficult to conclude that if we can model the workings of the brain accurately then we will model those subjective experiences as well.
The idea of a simulation requires that we accept the idea that our subjective experience would be a creation of the simulation and therefore, fundamentally, an illusion.
Illusion with respect to what? In the simulation everything is an illusion from the point of view of those running the simulation, but those subjective experiences are not an illusion with respect to those experiencing them.
In the Brain-in-a-vat, the nature, or indeed natures, of both our brain and our subjective experience remain exactly as we believe them to be.
And what exactly do you believe them to be?
With the idea of a simulation, both our subjective experience and the physical world are turned into illusions.
On.y from the point of view of those running the simulation. But whether they consider them illusions or not is pretty much irrelevant to those within the simulation.
The Brain-in-a-vat, although more realistic and conceivable, is nonetheless more metaphorical in its motivation. It doesn't even try to suggest that you really are a brain in a vat. Rather, it is an argument, a logical argument to explain why we cannot be certain of the reality of our perception of the physical world and, hence, of the reality of the physical world itself as we think of it.

The idea of the simulation is not an argument. It is a metaphysical claim about reality. A such, it is to be seen as connected with the idea that consciousness is a process and, therefore, to the idea that computers can become conscious. All that would be required would be that the software got to a sort of critical threshold of complexity.
Seems somewhat of a straw man, in that no one is comparing an argument to a notion. Some might compare the notion of a brain in a vat to be comparable in some respects to the notion of living in a simulation, and neither are in and of themselves an argument. Both can be used in an argument to explain how we can not be certain of our perceptions, etc.
The Brain-in-a-vat, on the contrary, suggests a decisive epistemological dualism between our own mind that we know and that we therefore know that it exists (Descartes' "I think, therefore I am") and the material world that we can only believe in, and that therefore we don't know that this material world really exists.
It might suggest it but I don’t think that’s essential for the argument being made, only that it helps confine the argument to matters that the audience might more readily understand and accept. If the argument is to explain why we can not be certain of our perceived reality, it makes sense not to throw in other ideas that might confuse people, or be a leap too far for some.
So I think you are perhaps reading into the argument more than there probably is.
In effect, these two ideas are polar opposite. The Brain-in-a-vat says the physical world may not exist, while the simulation says that our subjective experience may be just an illusion.
No, the brain in a vat doesn’t say that “the physical world may not exist”, rather it says that it exists differently to how we perceive it. The brain/mind exists in the meta-reality, but it’s subjective experience is in accord with the subjective reality.
The notion of living in a simulation says that both we and our subjective experience are an illusion with respect to the meta-reality. I.e. neither exist in the meta-reality, but it also says that we perceive the reality that we exist in. (Unless one is a brain in a vat while all the while being in a simulation!)

That is the difference.
To the extent that they are polar opposite, I don't see how anyone could see these two ideas as equally convincing. If you find them equally convincing, it is likely because you haven't understood at least one of them.
EB
They are not polar opposites at all. They are simply different ideas that have an overlap with the matters that they address.
But when you refer to them being convincing or not, convincing of what? Do you mean that you don’t see how anyone could find it equally convincing that we are a brain in a vat, and that we are living in a simulation?? Can you find examples of anyone who is convinced that they are a brain in a vat? Or even finds it more likely than not?
 
Tell you what, have a go anyway, and if he whips out a ruler then ignore him and continue with those who are willing to engage in what you have written?
I hadn't thought of that.

My initial thought was that a BiaV was far more feasible as SP puts it - in that it only requires fooling a single mind by manipulating the input, whereas a Matrix-style sim requires fooling 7 billion minds. But that's not really true: how would a BiaV make the distinction? For all it knows, it is part of a simulation that includes 7 billion other minds when instead it is simply fed the input that appears to be a world of 7 billion people.

The Brain-in-a-vat, although more realistic and conceivable, is nonetheless more metaphorical in its motivation. It doesn't even try to suggest that you really are a brain in a vat.

The idea of the simulation is not an argument. It is a metaphysical claim about reality.
I'm afraid I don't see how you make such a distinction without being arbitrary.

A sim does not have to be a "claim" any more than a BiaV is. Sure, it can be stated as a claim, but that's up to the claimant to defend.

Plato's cave is a

In effect, these two ideas are polar opposite. The Brain-in-a-vat says the physical world may not exist, while the simulation says that our subjective experience may be just an illusion.
The BiaV does not say "the physical world does not exist"; it says the world I perceive is not physical. As matter of fact, the BiaV explicitly requires a physical world to exist - the one in which the brain - and the vat - exist.
 
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Seems somewhat of a straw man, in that no one is comparing an argument to a notion. Some might compare the notion of a brain in a vat to be comparable in some respects to the notion of living in a simulation, and neither are in and of themselves an argument. Both can be used in an argument to explain how we can not be certain of our perceptions, etc.
Wiki: "The simplest use of brain-in-a-vat scenarios is as an argument for philosophical skepticism and solipsism."
Nobody is actually claiming that you are a brain in vat. It's an argument to make people understand the notion that we know our perceptions, not the physical world our perception seem to be perceptions of. Hence, the argument's implicit conclusion and therefore use is to suggest the physical world we believe exists may not in fact exist. All we know that it exists are our perceptions themselves. It's an epistemological claim.
In the case of the simulation, some people do argue that it is indeed likely that we are a simulation. It's a metaphysical claim.
EB
 
The BiaV does not say "the physical world does not exist";
I didn't say it did, contrary to what the quote marks you use imply.
EB
Sorry, "may" not exist:
The Brain-in-a-vat says the physical world may not exist...

To reiterate:
The BiaV does not say "the physical world may not exist"; it says the world I perceive is not physical. As matter of fact, the BiaV explicitly requires a physical world to exist - the one in which the brain - and the vat - exist.
 
Nobody is actually claiming that you are a brain in vat. It's an argument...

In the case of the simulation, some people do argue that it is indeed likely that we are a simulation.
I think the problem is that you are addressing the common usage of these things (i.e. what some people do argue), and not the nature of these things.

Both address broadly the same issue: the fact that we cannot know that what we experience is not a simulation. It just happens that one of them is used to make the point about an individual, whereas the other is used to make the point about all individuals simultaneously.

It is not a core part of the BiaV conjecture that it be more than merely a thought experiment, or less than an assertion.
It is not a core part of the simulation conjecture that it be more than merely a thought experiment, or less than an assertion.
 
Nobody is actually claiming that you are a brain in vat. It's an argument...
...
In the case of the simulation, some people do argue that it is indeed likely that we are a simulation. It's a metaphysical claim.
I know. My point is that you seem to want to make an issue out of the "idea of the simulation is not an argument". This is like trying to make an issue out of a car door not being a mode of transport. It's a non-issue. Noone is actually comparing the argument of the brain in the vat with just the notion/claim that we are living in a simulation.
As has been mentioned, by myself and DaveC, both notions (that we are a brain in a vat, and that we live in a simulation) can be used in arguments to address broadly the same issue - i.e. the nature of the reality we perceive.
 
The idea of the simulation is not an argument. It is a metaphysical claim about reality. A such, it is to be seen as connected with the idea that consciousness is a process and, therefore, to the idea that computers can become conscious. All that would be required would be that the software got to a sort of critical threshold of complexity.
IMO, the simulation of a reality is a projection of sensory inputs for cognitive processes contained in memory. Where memory is lacking, the brain learns what is projected into it, just as in real life.

Note that a "brain in a vat" has no sensory experiences other than what is artificially projected into the brain.
Thus any and all artificially experiential processes are perceived as reality, much like a dream.

Every day examples of total experiential disconnect from reality may be found in psychotic individuals. Their imaginary reality is all they know.

Even well developed brains can be fooled by optical illusions, where the brain creates a false illusionary image of an object which is not there!

and this persistent false impression of a shadowed tile which the brain is unable to adjust for.
 
Every day examples of total experiential disconnect from reality may be found in psychotic individuals. Their imaginary reality is all they know.
Nothing to do with being "psychotic". You don't understand the Brain-in-a-vat argument. It says all you will ever know is some image presented by your brain. Nothing to do with being "psychotic".
EB
 
It is my understanding that our brain does not need to work flawlessly. It needs to function only in a manner which promotes survival skills.

This is why people make different choices when presented with similar sensory experiences. The brain programs itself for survival techniques, not mathematical correctness.
 
Nothing to do with being "psychotic". You don't understand the Brain-in-a-vat argument. It says all you will ever know is some image presented by your brain. Nothing to do with being "psychotic".
EB
Why do you always begin with an ad hominem?
OK, here is the definition of "psychosis"
Psychosis is an abnormal condition of the mind that results in difficulties determining what is real and what is not.[4] Symptoms may include false beliefs (delusions) and seeing or hearing things that others do not see or hear (hallucinations).[4] Other symptoms may include incoherent speech and behavior that is inappropriate for the situation.[4] There may also be sleep problems, social withdrawal, lack of motivation, and difficulties carrying out daily activities
https://en.wikipedia.org/wiki/Psychosis

The point is that all you will ever know is a best guess image presented by your brain from secondary electrochemical translations of sensory inputs. Our brain is already in a vat and all it experiences and tries to project is an internal second hand translation of sensory inputs, based on cognitive abilities (learning) of the brain.

We always hallucinate our reality, albeit a "controlled hallucination". How else could we fit the image of an entire room inside our skull and make it look life-size? Amazing, no?
 
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Speakpigeon : Kind of curious whether you'll address this:
The BiaV does not say "the physical world may not exist"; it says the world I perceive is not physical. As matter of fact, the BiaV explicitly requires a physical world to exist - the one in which the brain - and the vat - exist.
Do you acknowledge it as a correction to your opening post?
 
There is a fundamental difference the Brain-in-a-vat argument and the idea that our entire world is a simulation running on a computer.

The Brain-in-a-vat seems within the reach of even human technology. In other words, it is a highly convincing and realistic scenario. A brain in a vat would presumably take the simulated physical world to be the actual world.

The idea of a simulation, that the world itself, including the brain experiencing this world, could be a simulation is much more fantastic and therefore somewhat more difficult to accept as a possibility.

The main sticking point, however, is that we still have no explanation as to how our subjective experience could possibly be a property or consequence of the way our brain works. The idea of a simulation requires that we accept the idea that our subjective experience would be a creation of the simulation and therefore, fundamentally, an illusion.

In the Brain-in-a-vat, the nature, or indeed natures, of both our brain and our subjective experience remain exactly as we believe them to be. With the idea of a simulation, both our subjective experience and the physical world are turned into illusions.

The Brain-in-a-vat, although more realistic and conceivable, is nonetheless more metaphorical in its motivation. It doesn't even try to suggest that you really are a brain in a vat. Rather, it is an argument, a logical argument to explain why we cannot be certain of the reality of our perception of the physical world and, hence, of the reality of the physical world itself as we think of it.

The idea of the simulation is not an argument. It is a metaphysical claim about reality. A such, it is to be seen as connected with the idea that consciousness is a process and, therefore, to the idea that computers can become conscious. All that would be required would be that the software got to a sort of critical threshold of complexity.

The Brain-in-a-vat, on the contrary, suggests a decisive epistemological dualism between our own mind that we know and that we therefore know that it exists (Descartes' "I think, therefore I am") and the material world that we can only believe in, and that therefore we don't know that this material world really exists.

In effect, these two ideas are polar opposite. The Brain-in-a-vat says the physical world may not exist, while the simulation says that our subjective experience may be just an illusion.

To the extent that they are polar opposite, I don't see how anyone could see these two ideas as equally convincing. If you find them equally convincing, it is likely because you haven't understood at least one of them.
EB


Quite a few near death experiencers seem to be coming back from their brushes with death with the idea that
our four dimensional space - time continuum is indeed comparable to a hologram, actually, a rather bad one in
comparison to the much, much, much better hologram environments that operate at higher vibrational levels!
 
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