Friday, February 06, 2015

What is the evidence...

That our sense experience is veridical? That we are not brains in vats and our experience is not systematically false?


43 comments:

im-skeptical said...

If you can't even believe what your senses tell you, what possible basis could you have for believing the fantastical stories in the bible?

Shackleman said...

The question is not directed at Christians. It's a straightforward question to anyone. Why not try to answer it, im-skeptical?

im-skeptical said...

You can make a philosophical case that what we experience is nothing but an illusion. But there isn't a single shred of evidence to support it.

On the other hand, there's ample reason to believe that our senses give us information that corresponds in some way to physical reality. We have shared or common experiences. We have machines that confirm or amplify the things our senses tell us. We are able to separate dreams and hallucinations from reality.

But my question was directed at Christians. So why not try to answer it?

Shackleman said...

If you google "Brain Games What a Colorful World" you will see a good illustration as to why your assertion that "our senses give us information that corresponds in some way to physical reality", carries no weight.

This simple example shows us that our senses are giving us *false* information. That the colors we see *are not there*. They do not exist in "physical reality".

If you can't trust your senses in this case, what warrant do you have for trusting any of them in any other case? Honest question.

im-skeptical said...

"This simple example shows us that our senses are giving us *false* information. That the colors we see *are not there*. They do not exist in "physical reality"."

That is not the issue that Victor raised. And you didn't listen to my answer. I agree completely that what we experience in our mind is only a *representation* of what exists in reality - it is not the reality itself. But Victor is asking whether there might be no correspondence at all between what we experience and what exists in reality. It's a completely different question.

msgrx said...

"We have shared or common experiences. We have machines that confirm or amplify the things our senses tell us."

Absent sense data, we have no way of knowing that these other people or machines even exist, let alone that they share or confirm our experiences. Your response here just begs the question, I'm afraid.

"We are able to separate dreams and hallucinations from reality."

Not always; viz. those cases of people who go on killing sprees because they heard the voice of Jesus telling them to. They were evidently pretty convinced that their hallucinations were in fact real. So how do we know that our own experience of reality isn't equally delusional?

"But my question was directed at Christians. So why not try to answer it?"

Because it's an obvious attempt to change the subject and derail the discussion. Duh.

B. Prokop said...

"But Victor is asking whether there might be no correspondence at all between what we experience and what exists in reality."

Not quite. In fact, Skep's "slight" misunderstanding results in a complete misreading of Victor's intent. Victor is not asking "whether there might be no correspondence at all between what we experience and what exists in reality". He knows very well that there is. What he is asking is, if you claim to go solely by "the evidence", then what justification do you have for assuming that anything you perceive is actually evidence of real things, and not a complete illusion - or even a fabrication? Completely different question.

im-skeptical said...

msgrx,

You didn't listen to my answer either.

"Absent sense data, we have no way of knowing that these other people or machines even exist, let alone that they share or confirm our experiences. Your response here just begs the question, I'm afraid."
- Absent sense data? That's all we have. That's all you have to know what exists in the world outside your mind. Should we think that it's all illusory? Not at all. There is absolutely no reason for me to believe that. I already addressed this. If you want to make the case that it's all an illusion, have at it. But I have no reason to believe you, and I have plenty of reason to disbelieve you. And please tell me what question I'm begging here.

"So how do we know that our own experience of reality isn't equally delusional?"
- I wasn't talking about whether an individual might be deluded. Let's concede that some people are deluded and get back to the central question. The point was that more generally, people who have normal sensory input are able to discern some representation of reality that agrees with that of others. We are not alone in our own world, disconnected from external reality.

"Because it's an obvious attempt to change the subject and derail the discussion. Duh."
- No, it isn't. It's a serious question that is directly related to the issue at hand. So go ahead and answer it.

im-skeptical said...

"What he is asking is, if you claim to go solely by "the evidence", then what justification do you have for assuming that anything you perceive is actually evidence of real things, and not a complete illusion - or even a fabrication? Completely different question."

Bob, You are completely unable to comprehend my answer. That is precisely the issue I am addressing.

msgrx said...

"You didn't listen to my answer either."

You've made variations of that statement to three commenters now. A simpler explanation would be that the answer you gave wasn't very good.

"Absent sense data? That's all we have."

First up, that claim isn't obviously true in the case of, e.g., mathematical truths, so there's no reason to accept your assertion here. Secondly, even if we accept it for the sake of argument, that doesn't actually prove that sense data is reliable or trustworthy. It might turn out that we don't have any reliable information about the external world.

"Should we think that it's all illusory? Not at all. There is absolutely no reason for me to believe that. I already addressed this. If you want to make the case that it's all an illusion, have at it. But I have no reason to believe you, and I have plenty of reason to disbelieve you."

Hey, you're the one making the claim (that we can be confident our sense data is veridical), so it's up to you to prove your assertion, not for anyone else to disprove it. Or does this sort of thing only hold when we're discussing God?

"And please tell me what question I'm begging here."

You're trying to claim that you can trust your senses by pointing to evidence that comes through your senses. The question begging is obvious to anyone with a brain.

"We are not alone in our own world, disconnected from external reality."

Since there's no reason to assume that your sense data about other people is at all accurate, you are once again begging the question.

"- No, it isn't. It's a serious question that is directly related to the issue at hand. So go ahead and answer it."

I'll happily answer it, once you provide a logically sound answer to Victor's post.

DJC said...

I think some skepticism is warranted. Consider what happens if humanity survives another thousand years. If Moore's law of doubling computing performance holds up, computing technology will be effortlessly able to simulate the entirety of any conscious experience/virtual brain, and further, simulate that experience to be taking place at any point in earth's history. Hence, I should be somewhat open to the possibility that I am a simulated organism rather than a biologically evolved one (and all that that entails veridically).

im-skeptical said...

"You've made variations of that statement to three commenters now. A simpler explanation would be that the answer you gave wasn't very good."
- I said it twice, not three times.

"First up, that claim isn't obviously true in the case of, e.g., mathematical truths, so there's no reason to accept your assertion here. Secondly, even if we accept it for the sake of argument, that doesn't actually prove that sense data is reliable or trustworthy. It might turn out that we don't have any reliable information about the external world."
- If we have no sense data at all, we have no knowledge about anything at all, including mathematical truths. We would have no language, no ability to read, write, or speak. We wouldn't even have a sense of self. In short, our world would be completely dark and empty.

"Hey, you're the one making the claim (that we can be confident our sense data is veridical), so it's up to you to prove your assertion, not for anyone else to disprove it."
- Where did I make this claim? Quote what I said.

"You're trying to claim that you can trust your senses by pointing to evidence that comes through your senses. The question begging is obvious to anyone with a brain."
- I said that the evidence of our senses is all we have to rely on. It gives us information that can be corroborated with others, and we have no good reason to believe that we shouldn't rely on it. There's nothing circular about that at all.

"Since there's no reason to assume that your sense data about other people is at all accurate, you are once again begging the question."
- There's no reason NOT to assume it. If you have one, please tell me what it is.

"I'll happily answer it, once you provide a logically sound answer to Victor's post."
- I don't think you will. So I'll go ahead and do it for you. You can answer in one of two ways: either you believe what your senses tell you, or you don't. If you believe what your senses tell you, then I will insist that you justify that position, just as you are demanding it of me. If, on the other hand, you you don't think that you can believe what your senses tell you, then you have no justification for believing anything at all, and that includes whatever you think you know about your Jesus. So which is it?

im-skeptical said...

DJC,

Yes, we can be open to the possibility, and I never said it wasn't possible. At the same time, there is still absolutely no reason to think such a thing is true.

Victor Reppert said...

Any reason to think it isn't true? One way around this is to shove the burden of proof to the other side. In fact, you can win any debate just by shoving the burden of proof to the other side, because you can ask for proof for the proof, and then proof for the proof for the proof, and then proof for the proof for the proof for the proof, and then proof for the proof for the proof for the proof for the proof.......

im-skeptical said...

"In fact, you can win any debate just by shoving the burden of proof to the other side, because you can ask for proof for the proof ..."

Yes, you can shift the burden of proof by asking for proof of the proof. Example: "What is the evidence ... That our sense experience is veridical?"

msgrx said...

Skeppy (the bush kangaroo):

"- I said it twice, not three times."

Oh dear, apparently maths isn't your strong suit either.

"And you didn't listen to my answer." (3.19 PM)

"You didn't listen to my answer either." (4.31 PM)

"You are completely unable to comprehend my answer." (5.16 PM)

"- If we have no sense data at all, we have no knowledge about anything at all, including mathematical truths. We would have no language, no ability to read, write, or speak. We wouldn't even have a sense of self. In short, our world would be completely dark and empty."

How do you know? Do you have sense data about what it's like to live without sense data?

" Where did I make this claim? Quote what I said."

OK:

"On the other hand, there's ample reason to believe that our senses give us information that corresponds in some way to physical reality." (Feb. 6th, 2.51 PM)

So, since you've decided to make the claim that there's "ample reason to believe" that our sense experiences are veridical, the onus is on you do defend that claim. Or to withdraw it. Either one's fine with me.

"It gives us information that can be corroborated with others,"

How do you know what others have experienced? Through sense data of what they tell you?

"and we have no good reason to believe that we shouldn't rely on it."

This being the skeppy equivalent of "There's no evidence that God *doesn't* exist!"

"I don't think you will. So I'll go ahead and do it for you. You can answer in one of two ways: either you believe what your senses tell you, or you don't. If you believe what your senses tell you, then I will insist that you justify that position, just as you are demanding it of me. If, on the other hand, you you don't think that you can believe what your senses tell you, then you have no justification for believing anything at all, and that includes whatever you think you know about your Jesus. So which is it?"

The issue isn't what I believe. You made the claim that we have ample reason to trust our senses, and now you're desperately squirming to try and get out of backing it up. I've no intention of helping you do so by derailing the conversation.

im-skeptical said...

msgrx,

So now we're resorting to name-calling. Getting frustrated, are we?

"Oh dear, apparently maths isn't your strong suit either."
- There's precious little math involved in counting from one to two. But obviously, it's beyond your ability. (By the way not reading something is different from not understanding something.)

"How do you know? Do you have sense data about what it's like to live without sense data?"
- That would be LACK of sense data. It is dark when you can't see. And without senses, we have no awareness or knowledge of the world, no ability to learn anything. Go ahead and try to refute this.

"So, since you've decided to make the claim that there's "ample reason to believe" that our sense experiences are veridical, the onus is on you do defend that claim. Or to withdraw it. Either one's fine with me."
- That's not what I said. I was referring to whether the external world is illusory, but nuance is not your specialty, is it? Why don't you go back and read it again. And as for placing the burden on me, you should also read my remark of 10:26PM. If you are interested in learning about how we know things, employ your senses to read about David Hume and empiricism. Even if you're a rationalist, you still have to use your senses to learn anything at all.

"How do you know what others have experienced? Through sense data of what they tell you?"
- Exactly. Boy, are you sharp.

"This being the skeppy equivalent of "There's no evidence that God *doesn't* exist!""
- Well, close. Not only is there no evidence - I've never even heard a serious argument that we can't use our senses to learn about our world. Is this your position?

"You made the claim that we have ample reason to trust our senses, and now you're desperately squirming to try and get out of backing it up."
- First, I did not make that claim. Second, I am not squirming out of anything. Third, If you want to make the case that we can't rely on our senses to learn about the world outside ourselves, feel free. Then, if I wish to refute your illogic, that will be my burden.

"I've no intention of helping you do so by derailing the conversation."
- I don't suppose you noticed that there was no conversation before I made my comment. But it certainly did initiate a conversation. I suggest you get a dictionary and look up the words 'initiate' and 'derail'. See if you can find any difference between them.

msgrx said...

Skeppy:

"So now we're resorting to name-calling. Getting frustrated, are we?"

No, just having a bit of fun. Let's face it, I'm unlikely to be having this argument for the intellectual stimulation it brings.

"(By the way not reading something is different from not understanding something.)"

That's why I said "variations on" that statement, not that statement full stop.

"- That would be LACK of sense data. It is dark when you can't see. And without senses, we have no awareness or knowledge of the world, no ability to learn anything. Go ahead and try to refute this."

Since you can't remember a time when you didn't have sense data, how do you know what knowledge you'd have absent it? You're just presuming empiricism here, rather than actually proving it.

"- That's not what I said. I was referring to whether the external world is illusory, but nuance is not your specialty, is it?"

Well that's just dumb. Nobody's been talking about whether the external world itself is illusory, but whether our perceptions of it are accurate.

"- Exactly. Boy, are you sharp."

Sharper than you, clearly, since I know that using sense data to prove the accuracy of sense data is a textbook example of circular reasoning. You might as well say "The Bible's right because it says so!"

"- First, I did not make that claim."

If you're going to lie about what you said, it's probably best to do it somewhere where people can't just scroll up and see for themselves that you're lying.

"- I don't suppose you noticed that there was no conversation before I made my comment. But it certainly did initiate a conversation. I suggest you get a dictionary and look up the words 'initiate' and 'derail'. See if you can find any difference between them."

You didn't want to engage in the sort of self-reflection Victor's question required, so you tried to change the subject. Don't think you're fooling anyone regarding your motivations.

im-skeptical said...

msgrx,

By now it is clear that I've been trying to talk to someone who comprehends absolutely nothing, so this will be my final comment to you.

You don't even know what the topic of this post is ("Nobody's been talking about whether the external world itself is illusory,"), and yet you accuse me of trying to derail it.

You keep telling my that I'm trying to prove something (that our sense data is accurate), when in fact I haven't been trying to prove anything, nor have I made any such assertion. I have simply been responding to idiotic statements made by you. ("using sense data to prove the accuracy of sense data is a textbook example of circular reasoning.")

You keep trying to tell me I have the burden of proof. What am I supposed to prove? Like I said before, if you want to make a claim that we can't rely on our senses to know something about the world, go ahead and do so. I'm not the one making claims here, and I certainly wouldn't be so stupid as to claim something like that that defies what is universally accepted (except perhaps for a small number of people who are either idiots or part of some philosophical extreme fringe). But go ahead - make your claim.

And this brings me back to my original question. You are obviously too stupid to understand the point it makes ("You didn't want to engage in the sort of self-reflection Victor's question required"). Is your name Karl, by any chance?

B. Prokop said...

"By now it is clear that I've been trying to talk to someone who comprehends absolutely nothing"

We've heard this (many, many times) before. Plain English translation: Anyone who does not agree with Skep "comprehends absolutely nothing"!

im-skeptical said...

"Anyone who does not agree with Skep "comprehends absolutely nothing"!"

It has nothing to do with whether he agrees with me - he can't even figure out the topic of a one-sentence post.

Victor Reppert said...

I-S wrote: On the other hand, there's ample reason to believe that our senses give us information that corresponds in some way to physical reality. We have shared or common experiences. We have machines that confirm or amplify the things our senses tell us. We are able to separate dreams and hallucinations from reality.

But the vat-keepers are smart people, aren't they? Couldn't they give us experiences that fit this pattern to make sure we don't figure out there game and realize that we are just brains in vats?

im-skeptical said...

As I said to DJC, "Yes, we can be open to the possibility, and I never said it wasn't possible. At the same time, there is still absolutely no reason to think such a thing is true."

Maybe my conscious experience is just a computer simulation. I don't have any way of proving that it isn't. But I don't the slightest reason to think that may be the case.

So what should I believe? Is the world real, or is it all an elaborate hoax? Why would someone go to the trouble to create all this, and keep me in that dark about it? I think I should go with the explanation that seems more reasonable, more likely, and far simpler.

Victor Reppert said...

Well, it is often argued that if you are making the positive existence claim, you have the burden of proof. Thus

1) God exists

has the burden of proof, while

2) God does not exist

does not.

Similarly

1) The external world exists

has the burden of proof while

2) The external world does not exist

does not.

im-skeptical said...

Victor,

The scenario you posed postulates a brain-in-a-vat, which presumes an external world (a very unlikely one). But you're the one who posed the question. I didn't. I've made no positive existence claim (although it is what I believe). Surely you're not a radical solipsist. Do you believe the world exists? Can you prove it? What gives you the right to simply pose this question and insist that I must prove it?

Victor Reppert said...

The whole point here is a reductio ad absurdum on oversimplified rules concerning who has the burden of proof.

im-skeptical said...

As reductios go, this is a failure. The two situations are very different, and so not comparable.

One is a legitimate matter of dispute (believed by some, not by others) - the other one isn't.

One is the subject of many "proofs" - the other can't be proven in principle.

Proponents of one claim to have all kinds of observable evidence for their position - there can't possibly be any observable evidence in support of the other.

cl said...

LOLOLOL!

Great volleys in these recent posts, Vic, lovin' it.

Watching im-skeptical fumble and try to shift the burden of proof simply reiterates the OP. Too classic! It's hilarious how im-skeptical -- within only a few comments -- managed to accuse multiple commenters of not understanding his/her "answer" ... I say this is hilarious because no answer was given, simply a question that revealed precisely what others perceived: "slight" misunderstanding on the part of im-skeptical.

As was said elsewhere, deny, dodge, repeat!

"You're trying to claim that you can trust your senses by pointing to evidence that comes through your senses. The question begging is obvious to anyone with a brain."

Yes, exactly!!

The following comment from im-skeptical illustrates perfectly the typical Gnu Atheist / scientism / pseudo-skeptical mindset:

"There's precious little math involved in counting from one to two. But obviously, it's beyond your ability."

...and yet, a few comments previous, msgrx provided the MATHEMATICAL, EMPIRICAL PROOF that im-skeptical actually did say it three times! You'd think a person truly committed to following the evidence wherever it leads would simply pause and say, "Hey, shoot, you're right, I did say that three times," and move on. But NOOOO... deny, dodge, accuse others of inability to comprehend, repeat!

Post-modern "rationalism" on display for all, don't forget your popcorn!!!! LOL

msgrx, I salute you. Heck, I salute all of you, except im-skeptical for blatant disrespect to reason.

cl said...

Another funny tactic of the pseudo-rational atheist:

"I've made no positive existence claim (although it is what I believe)."

..they think because they deny God's existence that such entails no burden of proof, but the denial of God's existence entails several positive assertions that each require their own burden of proof.

I rarely see atheists take that tack. In my experience they'd rather just... deny, deny, deny, then draw a line in the sand and expect their interlocutor to do all the work.

im-skeptical said...

cl,

Aren't you the one who sulked away crying because I postulated that the supposed miraculous event that occurred in your living room (flying objects) was not actually a miracle?

LOLOLOL!

Papalinton said...

As can be clearly seen, and as cl wonderfully demonstrates, when one believes in gods, ghosts, demons, angels and dead rising people, one will believe anything.

cl said...

IM-SKEPTICAL

"Aren't you the one who sulked away crying because I postulated that the supposed miraculous event that occurred in your living room (flying objects) was not actually a miracle?"

No, actually, like most everything else you got this wrong too. I didn't postulate that said event was a miracle, I said that it violated all known laws of naturalist mechanics and that the onus was on you to come up with a better explanation to fit the evidence.

Your response, of course, was to simply deny and dodge -- as you do here.

PAPALINTON

"As can be clearly seen, and as cl wonderfully demonstrates, when one believes in gods, ghosts, demons, angels and dead rising people, one will believe anything."

Right. And as has been clearly seen here, as you've wonderfully demonstrated, when one is committed to their position no matter what the evidence says, one will shamelessly PLAGIARIZE other people's writing to pass off as one's own in a sadly misguided attempt to bolster intellectual credos.

Pathetic, the pseudo-rationalist scene is.

Aragorn said...

Ridiculous reductio, but please continue. You keep on dismissing IS but you can't seem to knock him/her down. WTG IS!

Victor Reppert said...

So, IS you are saying that no evidence is POSSIBLE for theism? Interesting coming from someone who constantly says "If you only had evidence."

im-skeptical said...

Victor, in my comment about your reductio, I compared 'one' (theism) against 'the other' (external world belief). If you deny the evidence of the senses, there is no possible evidence for it and no possible way to prove it. Theists, on the other hand, insist that they DO have evidence for God, and that they CAN prove its existence. Or do you deny these claims?

Victor Reppert said...

The principle says that if you make the positive existence claim, you have the burden of proof. The cases don't have to be parallel in all respects, the principle puts the burden on both God and the external world.

If you want to impose the burden of proof on theism, you need to revise the principle.

im-skeptical said...

Victor,

I have said repeatedly that I'm not making a positive existence claim. If you want mo to prove what I have claimed, fine - wait until I make a claim. I have reason to believe what my senses tell me. I believe that sense information is the only way we have of knowing anything about the world.

I reject the notion that people have an extra sense (Plantinga's sensus divinitatus), which is contrived as a false justification for believing in something imaginary. People who cite this as a way of knowing about God's existence are not relying on their senses.

Victor Reppert said...

Your senses tell you that physical objects exist, right? Isn't that an existence claim?

im-skeptical said...

No, it's my belief. If you can accept that the senses are the basis of truth in existence claims, then OK - I can say that based on the evidence of my senses, I accept the truth of the existence of the world outside my brain. But I don't think that can be proved absolutely.

Furthermore, I still think you believe the external world exists, as I do. And I think you agree that it can't be proved absolutely (without making an assumption about what we can know). This is very different from claiming to know that God exists, as many theists do.

Dan Gillson said...

"No, it's my belief. If you can accept that the senses are the basis of truth in existence claims, then OK - I can say that based on the evidence of my senses, I accept the truth of the existence of the world outside my brain. But I don't think that can be proved absolutely."

So, you have ... *gasp* ... FAITH that that external world exists!?!

"Furthermore, I still think you believe the external world exists, as I do. And I think you agree that it can't be proved absolutely (without making an assumption about what we can know). This is very different from claiming to know that God exists, as many theists do."

Yeah it's different because, theism ... gross. Amirite?

im-skeptical said...

"Amirite?"

Not by a long shot.

But since you pretend to be so fucking superior, why don't you tell us your basis to believe what you believe?

Dan Gillson said...

im-skeptical,

"But since you pretend to be so fucking superior ... "

That's, like, your opinion, man.

" ... [W]hy don't you tell us your basis to believe what you believe?"

No.

im-skeptical said...

Dan,

Yes it is my opinion. And since you obviously have nothing to offer in this discussion, your trolling is not appreciated. Butt out.