No. Dave and I don't know whether we're brains in vats or not. We don't claim knowledge in this respect. You do. A brain in a vat would have faith - especially if the brain is you. You claim "I know that I'm not a brain in a vat." I'm not sure whether you consider that a positive claim or a negative one. On the one hand, you are claiming to have knowledge of something, as opposed to lacking knowledge, so that's a positive claim. On the other than, you are claiming you are not something, which is a negative claim. I can't immediately work out how to recast that negative claim as something positive, but maybe you can do it. Atheists, by the way, do not assert that God does not exist. They just don't believe that God exists. See the difference? There is a knowledge claim; and there is a statement about possibility. And, separate to that, there is a statement about belief.
karenmansker: First, bear in mind that we need not be dealing with a physical brain in a physical vat here. For more on that, see my earlier posts. Second, let's assume we are talking about a physical brain in a physical vat (which is, after all, one possibility). How did it get there? There are many possibilities. Maybe it was grown there from scratch. Maybe it was removed from a real live human body - yours, maybe, while you were asleep. No doubt there are other possibilities. And whose vat is it? Could be in a lab run by alien beings. Or humans with advanced technology. Or a secret government facility hiding technology from the general population. And there are other possibilities. That's kind of another issue, although possibly related. Yes. In practical terms, not a bit. But in some metaphysical sense, maybe. And as a philosophical exercise concerned with exploring what we can actually know about our world and what we can't, it's quite important.
If you don't know you're a brain in a vat, how can your claim 'we don't know we're brains in vats' mean anything? After all, you may be a brain in a vat. How can you know this if you think it possible you could be a brain in a vat? How do you know I did? If I am a human being (which I am), we can assume that I am not simultaneosly anything else. Some do. Others claim there is no evidence for God's existing, but deny all evidences put forward, saying they are not evidences for God. Effectively they can continue denying all evidences for God, thereby keeping God in the non existent pile. Ultimately it amounts to the same thing, unless you can cite what would be evidence of God's existence. jan.
Can a brain entertain anything? Is it a brain that came up with the notion, or is it a person? Is it your brain that is discussing, or is it you? I suggest we look into the capability of brains. The same way we judge anything else? We start from what we know? If we are a brain in a vat, then we start from there. If we are human beings we start from there. Where would you start from? Yes. I possess a body/brain, hands, feet, and so on. When you say your hands, your brain, is that purely grammar, or is there some truth to the claims? Such as? I agree. This world is an amazing piece of technology. In fact it is so good, it is very easy to think this is real. Evidence of a supreme intelligence. I believe that this idea of a brain in a vat, or a evil demon, is an indirect testament to that supreme intelligence. What does that say about the possibility of being a brain in a vat? You can't even know if those words makes sense. jan.
Jan Ardena: If I don't know what the weather is like outside, how can my claim that I don't know what the weather is like outside mean anything? Please Register or Log in to view the hidden image! Because you told me. I read it in a post you wrote in this thread. Are you playing a silly game here? If you have a point to make, please make it. What is a human being? It's hard to cite what would be evidence, since God is constructed so as to be essentially unfalsifiable. In a similar context, see my post here: http://sciforums.com/threads/evidence-of-hell.158177/page-11#post-3420866 Great! It's about time you started thinking about that. So, tell me what you think about the answers to these questions you've posed. Then we can discuss. You're begging the question. Recall that our debate is all about what you claim you know. That's another can of worms you've opened, right there. What exactly is this "I" you refer to when you talk about "my" this or "my" that, or when you say "I know" or "I think" or "I want" or "I feel"? Try to be specific when you answer this. For starters, see the post I linked to just above. Yes! No necessarily. For example, at any given time, there's no need to simulate an entire world. If you're a brain in a vat, there's only the need to simulate enough to give you verisimilitude as you are right now. The problem that must be solved is finite. No. Conceivably, all this could be run by a bunch of clever guys or girls with some beefed-up computer equipment and enough knowledge of brain biology. Nothing. But it says you were wrong to make a knowledge claim you can't support.
Because ''weather'' exists, and there is a location known as outside, depending on your location. So when you ask the question, others can formulate a meaning. Where is this brain in the vat? That's right, it is a mental image. How do you know you did? If you could be a brain in a vat, non of this may be real. Just by accepting you could be a BIV means you give up all rights to knowledge of anything. It's not silly. You alluded to it yourself. You can't really know what is reality if you are a brain in a vat. That means if you think it is possible that you are, then it is possible that I didn't write it, or that I even exist. Those must also be possibilities. I asked you. You're the one claiming we don't know if we're brains in vats. If we claim to know something, we have a starting position. Right? You claim that I wrote something which you replied to. What position did you claim that from? The possibility of being a brain in a vat, or the reality of being a human being? It cannot be both. Not for me. It's a really simple observation. Do we possess our arms and legs, or are we our are arms and legs?? Say's who? Explain how that could possibly be. Erm, no. It says that you cannot make any truth, or knowledge claims, because it is possible that you could be a brain in a box. Funnily enough you do make truth and knowledge claims, so you are not a BIaV. Steeeerrrike! Please Register or Log in to view the hidden image! I can make sense of the world. If you think it is possible you could be a brain in a vat, you can't. Whether you believe it to be true or not? But I know you can make sense of the world. jan.
I didn't say it negates the possibility. Why do you believe there is a possibility? If you think it is possible to not know what is real, from what is not real, then you can't know what you're typing makes any sense. If what you're typing makes sense to you, then you are making a knowledge claim, that it makes sense. So either there is a possibility of BIV, or there isn't. You can't have you cake, and eat it. I see pretending to accept, and playing mind games. The possibility of being a brain in a vat? You're right, there is no evidence that it exists, outside of minds. Thanks Sarkus. If it is possible that we could be brains in vats, do you have any objection to my answer being ''because it is impossible''? Is it possible that I am correct? The thing is, you wouldn't know, because it is possible that it could either be correct, and/or wrong. If it is possible that you are a brain in a vat, and cannot know anything with any amount of certainty, then it is possible that I am correct, incorrect, or both. You have no basis in justifying any type of evidence. Not really. For such an atheist, God doesn't exist. Meaning he cannot perceive God to exist. It is true for him. Truth and facts are two different things. We're talking about possibilities. If we believe it is possible that we could be brains in a vat, then we give up the possibility of knowing anything, with any degree of certainty. No matter how much evidence or facts there appear to be. If we believe it is possible that God exists, we can know things, we can understand the difference between what is truth and what is false. The latter appears to be the case. If we are a brain in a vat, how do know we are a brain in a vat let alone dictate the conditions of our position. If we are a brain in a vat, we know absolutely nothing with any degree of certainty. Anything could happen. Eh? Or nothing could happen. The possibility leads to absurdity. It is the fact that you're human that allows you airbrush the absurdity out. How could you postulate that, if you accept the possibility of BIV? How human of you. Nice airbrushing. jan.
Jan still doesn't seem to understand what a BiaV is. He keeps referring to it like it's an automaton - as if it is somehow not a fully-functioning human mind.) Regardless, the pattern of denial is consistent. He thinks he can wish his way out of the fallibility of his senses. He thinks that, if he believes and asserts he's not a BiaV then somehow that means he isn't. Which is exactly the same stance as with God. He believes and asserts that God exists and somehow that means it does. In both cases, the "somehow" is what the rest of us define as "faith". We should not have expected Jan to think any other way about BiaV.
You said: "The fact that I can have faith at all, is but one reason why I know I'm not a brain in a vat." - i.e. the having of faith enables you to know you are not a brain in a vat. This is thus you saying that having faith negates the possibility - i.e. means that there is no possibility. If there was still a possibility despite the holding of faith then you couldn't know you weren't simply from holding of faith. Simples really. I'm sure it's been mentioned before but either you lack the ability to comprehend the implications of what you write, or you write before thinking through the implications adequately. Because it hasn't been discounted as being impossible. My understanding and knowledge is limited to this local reality, not the wider reality. Within this local reality I know that what I type makes sense because people respond to it in a manner consistent with them understanding it. It is logical that in order to make sense in a simulation I must be able to make sense of the simulation and converse in a manner that both I and the one I am conversing with understand. Whether it is in the same language native to the BiaV is irrelevant, it is at least a language that I/others understand in the local reality, and the ability to converse consistently within the local reality leads one to conclude that what I am typing within the local reality makes sense. Again, simples really. Please Register or Log in to view the hidden image! And therein lies your weakness, it seems. If you genuinely can't comprehend then I can see how the vast majority of this thread must seem like you're swimming in treacle trying to stay afloat. Now prove that it doesn't exist. Simples really. We can get on to how absence of evidence is not evidence of absence later. If you are claiming that it is impossible then the onus is on you to provide the proof that it is impossible. Otherwise it remains a possibility as far as we can tell, and if we are absolutely unable to tell then it will remain a possibility. If the matter in question is within the local reality then the evidence need only be that available within the local reality. But evidence found within the local reality will have difficulty being applicable to the wider reality. I know they are different, but probably not in the way you think: facts are data points that match reality while truth is a property of logic, maths, sentences, propositions and conclusions etc. "True for him" is merely a matter of subjectivity while we are discussing the objective. Philosophically speaking, yes, when in the context of the BiaV thought experiment. Usually, however, the default context is taken to be the local reality - in which case all terms such as knowledge, facts etc relate to that local reality. This appears to me a non sequitur - how do you get from the believing "it is possible that God exists" to "we can know things"? What is it about believing it is possible that God exists that enables us to know things. And why can we not understand the difference between what is truth and false if God does not exist? We don't know. We can't know. That's the point. But it remains a possibility. Indeed. But in usual context we don't consider the possibility, and our context is merely our local reality. Not absurdity - simply to an acknowledgement of ignorance, and to an acceptance that in the face of such ignorance we do not practically consider such possibilities other than in such thought experiments. Being human per se has nothing to do with it. It merely requires the comprehension of the limits of what we can know... i.e. our local reality. Note that I said "if". i.e. if the reality is that we are merely human, and that local reality is as wide as it gets... in which case there is no BiaV. But I do not know that this is the situation, hence the "if". Again, no airbrushing needed, Jan.
Jan Ardena: You mean you believe there is an outside with weather and so on. If you are a brain in a vat, you have no way of accessing the information as to where that brain is, physically. In the wider reality that Sarkus speaks of, yes. In the local reality of vat-world, no. Look! You said it yourself: You can't really know what is reality if you are a brain in a vat. But you claim to know what is reality. You're arguing against yourself, unless you can prove that you're not a brain in a vat. Which you can't. Ok. Let's take a quick look. Can a brain entertain anything? Yes. For example, if you are a brain in a vat, you are, right now, entertaining the idea that we're having a discussion about brains in vats. Is it a brain that came up with the notion, or is it a person? I can't answer this unless you can explain to me what you see as the difference between a brain and a person. Is it your brain that is discussing, or is it you? If you're a brain in vat, the brain is you. I suggest we look into the capability of brains. What capacities, specifically, do you think are relevant here? No. Knowing something is a conclusion, not a starting position. We start not knowing things. If you are a brain in a vat, then it came from the reality of your being a brain in a vat. If you are not a brain in vat, then it came from that reality. You avoided answering the question I asked you. Personally, I think of "my arm" as "mine" because it is attached to "my body". "My body" is mine because I appear to be able to control it, I appear to have sensory impressions from it and so on. As far as I am aware, you cannot control my arm or feel the touch that my arm feels. I believe that my arm is controlled by my brain. However, this is a theoretical kind of knowledge, since I do not directly perceive my brain in any way. The "real" control of my arm could conceivably come from elsewhere (like a brain in a vat, for example). As for "me" as the being who has the thoughts and desires and stuff, I believe that "me" is a construct of my brain. However, as I said, I have no way of knowing where that "me" is physically located, just as I have no way of knowing where my brain is physically located. As far as I can tell, you have no better claim to knowledge about yourself than I have about myself. Says Professor Science. I already did. The details aren't important to the current discussion. Sorry, but you're still not getting it, so that shout of triump is a premature celebration for you. You lost track of the idea of a local reality vs the wider reality again (or never grasped the concept in the first place). You can make knowledge claims that appear to you to be perfectly consistent with everything you perceive in the local reality. But you have zero basis on which to make knowledge claims about the wider reality. Your mistake all along has been to assume that your local reality is all that can ever be. For somebody who believes in God and other supernatural things, your resistance here to the idea that there might be more to the world than you can perceive seems inconsistent. Then again, you always sound like you think you have it all worked out, so may it is consistent with your world view after all. Why not?
Also... You're disingenously trying to smear the distinction between possibility and actuality here. Don't think that people can't see what you're doing there. The possibility of being a brain in a vat remains open unless you can show that such a thing is impossible. On the other hand, the actuality of you knowing that you're not a brain in a vat is something that needs to be proven. This point has been made so many times to you that you can't pretend you can't tell the difference. Yes. You haven't shown it is impossible. And you have no basis to make the knowledge claim you have made. Q.E.D. Truth and facts are two different things? Oh, are we going to head off on a new Jan Ardena diversion now, in which Jan tries to redefine terms like "truth" and "fact" to suit himself? How unexpected. Wrong. You can be reasonably certain about a whole bunch of things in your local reality, whether or not you're a brain in a vat. As to the wider reality, there's never going to be much certainty about that. That's more a matter of guesswork or, in religious terms that you can relate to, faith. Are you saying God somehow tells you that you're not a brain in a vat? Is your belief that you're not a brain in vat dependent on your religious beliefs, then? Yes! Correct. It's fun to watch you struggle with this. Occasionally, you seem to get it, then a moment later you're all at sea again. Maybe you need to take some time out and think about this carefully.
I've been resting mentioning this but it's just to glaring. Many decades ago, I saw a movie about a yong man rescued forceably from a cult. When he was being deprogrammed, he would occasionally find himself logically painted into a corner. His convictoon would crack, and he'd panic. He'd close his eyes and chant his mantra. "Bring in the money! Stay awake! Smash out Satan! Bringinthemoney!Stayawake!SmashoutSatan!" (Not that I'm suggesting that our friend here is brainwashed, but you can see the shift when his convictions are shaken.)
So . . . . with all this Brain-in-a-Vat (BIV)/Not-in-a-Vat discussion . . . . . . . it's fine for a meaningless philosophical discussion, but allow me to ask a 'scientific' question . . . has ANYONE made an observation of a laboratory Brain-in-a-Vat, wherein the brain was capable (alive?) enough to even ask such a question. Remember . . . . the scientific method begins with "observation(s)" and mental inquiry regarding such 'observations'!! It would appear (IMO) that this whole BIV discussion is somewhat moot and particularly 'non-scientific'.
No. That's why it's in the General Philosophy forum and not General Science. Of course, if your world is simulated, the "actual" level of technology in the "real" world could be very different to the level of technology you're currently aware of. As an analogy, think of a computer game that simulates a medieval world, with horses and swords and all villages and all that. If you were a simulated person in that computer world, you'd know nothing of computers or cars or aeroplanes. But that wouldn't change the fact that you were being simulated in an actual computer. You just wouldn't/couldn't know that. Now consider your current situation, right here and now. There's no way, from your point of view, that you can know that you aren't part of a simulation in some advanced computer system that exists in a "reality" that is not accessible to you. The fact that the relevant technology does not exist in your perceived world is neither here nor there.
To be fair to Jan, there are differences between the two, although they are often used synonymously. As mentioned previously, a fact is a data point that corresponds to actuality. Within this discussion we might actually need to refer to fact-L and fact-W to denote what is a fact in the local reality and what is a fact in the wider reality. A fact in the wider reality can not be known within the local, and a fact in the local reality may not hold within the wider, it is only certainly factual within the context of the local reality. Anyhoo, a truth on the other hand is a relational value, in mathematics, logic etc. It is true that 1+1 = 2, for example, and it is also true that if all men are geese, and if Socrates is a man, then Socrates is a goose. Perhaps a small semantic difference, and likely not what Jan was referring to. More likely Jan was referring to the fact being something that corresponds to reality for all people, and a truth being something that need only correspond to one person's reality - I.e. a fact is an objective truth whereas a truth need only be subjective. Thus what is true for one person might not be true for another: if one person thinks a picture beautiful he will think that it is true that the picture is beautiful. This is different to saying that it is a fact that the picture is beautiful. I think some people do struggle with the nature of philosophical issues, since they may have no obvious apparent utility to our practical lives. They struggle with accepting the mere possibility of something that may consider practically absurd, or not otherwise worth considering outside of the confines of the debate. And that accepting the possibility of something is to insist on it having an importance in their practical lives. Which they can't bring themselves to do, so reject it as a possibility. Or something like that. Please Register or Log in to view the hidden image!
There are two centers of consciousness in the human brain. The primary center is shared with animals and is called the inner self. Humans have a secondary center, which allows choice apart from animal instincts. This secondary center evolved more recently and is often called the ego. The brain in the vat is when the inners self is creating arousal and inducing the brain's firmware. The computer simulation is part of your own brain's capacity, with the ego often not aware of a secondary; simulation, impacting perception of reality. For example, say I dropped you off in the woods at night without a flash light. If you are not used to the outdoors at night, the rustling of the bushes or the shadow in the distance, might appear to be a wild animal. The animal is not there, in reality, but the unconscious is creating a simulation and projection that superimpose, making the ego's imagination goes wild. Some people may start to run, as though reacting to real hard data. Such a person cannot differentiate between the two centers. That example is easy to see. There are more subtle examples. Say you play sports and you are having your best day, ever; glory days. The ego will attribute this to itself, but in reality the inner self is assisting the ego, with the main frame parts of the brain. The ancients were more conscious of this and call it the blessing of the gods; projection and induction of the inner self and helpful firmware; reactions of an animal. Falling in love is not something we can consciously do, at will. Most people attribute this fickle event to fate. But in reality, it occurs if and when the inner self turns on the software simulation of love and romance. Then the world becomes beautiful.
Sounds strangely close to alien abduction. This subject started by anyone not of the respectable science tribe here would be ridiculed. Um, like MR or really any nobody in the fringe section.
Brain-in-a-vat is a well-established philosophical thought experiment with a venerable history going back to René "I think therefore I am" Descartes. "In philosophy, the brain in a vat (alternately known as brain in a jar) is a scenario used in a variety of thought experiments intended to draw out certain features of our ideas of knowledge, reality, truth, mind, consciousness and meaning. It is an updated version of René Descartes' Evil Demon thought experiment originated by Gilbert Harman." https://en.wikipedia.org/wiki/Brain_in_a_vat This is what Jan has been struggling with: "Since the brain in a vat gives and receives exactly the same impulses as it would if it were in a skull, and since these are its only way of interacting with its environment, then it is not possible to tell, from the perspective of that brain, whether it is in a skull or a vat. Yet in the first case most of the person's beliefs may be true (if they believe, say, that they are walking down the street, or eating ice-cream); in the latter case their beliefs are false. Since the argument says one cannot know whether one is a brain in a vat, then one cannot know whether most of one's beliefs might be completely false. Since, in principle, it is impossible to rule out oneself being a brain in a vat, there cannot be good grounds for believing any of the things one believes; a skeptical argument would contend that one certainly cannot know them, raising issues with the definition of knowledge."
To explore that experimentally, one could start a topic in the Fringe section asking about the mere possibility of ghosts. Rather than asserting that "ghosts exist" or suggesting "here is a particular instance of a genuine ghost", or even "ghosts do not exist" (IF all such cognitive stances are falling out of preset ideology). Perhaps this has been attempted before in the past, either intentionally or (better) unintentionally. Whereby the results / responses would then be more "natural" or not suspect of having been compromised beforehand by activity in this thread. It's a tad surprising that solipsism hasn't reared its head so far in association with this BIV discussion (or has it?). If there's only one brain in a vat rather than a community of them inter-subjectively connected, then BIV would at least be rubbing shoulders with the idea. What arguably prevents complete conflation with solipsism is that the outward appearances of both non-living objects and people could have their initial origins (before becoming pseudo-sensory data fed to the vat) as the subroutines of computer programs and stored bits in a drive. Just any kind of super-external provenance for those everyday phenomena which the brain is sensing (even if those sources have been transfigured late the process) would still equate to their ultimate manner of existence being independent of the imprisoned brain's will, desires, and neural modifications. OTOH, though, there would definitely be a lack of "other minds" in the fullest meaning of such. Similar to how the outward appearance of other humans in dreams does not realize thoughts and experiences truly transpiring in their heads, even though the body behavior and speech would lead to that conclusion.
