But...this is precisely not what you've been saying? Did you even read the post you quoted?

No, like I said, "what I accepted was that there are times when I can't tell whether or not what seems to be there is there", but in the wider context of my life hallucination is meaningful as an anomalous, disruptive event. This is just a tedious disagreement about what "cannot tell" means. Perhaps I was unclear.

So, is it possible on your view that all of your experiences could be hallucinations? If not, why not?

My position doesn't demand that I address such a possibility, because I have been fairly explicitly presuming all along that it is not the case. That is, although I accept for the sake of argument that "every instance of an experience is one that is in principle indistinguishable between the two types you've mentioned", I take it for granted (as I've said) that such instances as are hallucinations are rare interruptions in perception.

This would be a problem only if I were trying to establish the distinction, to prove against the sceptic that it was real.

Again, it's not some external position, 'the skeptic,' that threatens you -- it's that your own position is internally incoherent. Your position does demand that you address the possibility insofar as your own beliefs are in tension with each other.

But I can see you're not interested in this, so I will stop.

You're right, I'm not very interested, but I'm smarting from the charge of internal incoherence, so let me try again.

Between making use of the distinction and saying that I can't tell the difference at any particular time there is a tension from a sceptical standpoint, but not an inconsistency, for making use of the distinction does not depend on my being able to tell the difference during any particular instance of experience.

The idea that experience is all just a dream, an hallucination or virtual is senseless without the distinction between real and illusory, so I haven't said the distinction is senseless at all, which appears to be what you think I said.

What does your idealist say that experience is? Does the idealist deny the reality of the causal relationship between things and our visual perceptions of them, as it is understood by science? It is on the basis of 'common sense' but nowadays even more so in light of our observations and analyses of the things we visually perceive, of the means (light) of our visual perception and the whole complex and very coherent and consistent story that science tells us about the world that we observe, that we now make the distinction between 'real' and 'virtual' objects.

Virtual objects do not have any causal physical relationship to us. Why is that not sufficient to underpin the distinction? If you think it is insufficient or wrong somehow, then explain what reasons we have to disbelieve what science tells us about visual perception, about the causal relationships between us and the things we see.

So, is it possible on your view that all of your experiences could be hallucinations? If not, why not? — The Great Whatever

Insofar as immediate sensations go, yes. Since there is no yet any experience which shows them to be real or a hallucination, no relation of the sensations to other experiences which amounts to knowing the difference of "real" and virtual," it is possible that any such immediate sensation could be an hallucination.

But that tells us nothing. Possibility is not actuality. Nor does it get removed when one possible outcome is actual as opposed to another. It is possible, for example, that I will make submit this post. It is also possible I will not submit this post. Both possibilities are present, whether I submit the post or not. Both are so whether I know I'm going to submit this post in the future or not. Possibility has no consequence for either what exists or what we know (that's really just member of the former set; our instances of knowledge are states of existence).

So the possibility of hallucination is irrelevant to the direct realist. They are interested in the actual (whether "real" or "virtual"): what exists, how the things we experience relate to others, and what is true any time we are aware of these existing states.

By "found himself" I meant to suggest that this is what he experienced. One person experiences himself waking up in a post apocalyptic world and another doesn't. Who is having the real experiences and who is having the false ones? — Michael

Neither. Both experiences are of "real" worlds. Within the Matrix, the person is living out a life where interactions between their body (in the Matrix) have consequences for their life (in the Matrix). Even bodies in the outside world can be affected by events in the Matrix (people getting injured).

The Matrix may be the single worst example of a "virtual" world there has ever been. There is nothing illusionary about it. Neo did not find out the world he was in wasn't real. He merely found out there was another (or maybe "wider" ) real world.

I'd have thought that quantum mechanics has already shown that our sensory apparatuses are not causally related to anything like the objects we take ourselves to be perceiving (instead they're causally related to things very unlike the objects we take ourselves to be perceiving). But it doesn't then follow that the apple we see is fake. — Michael

Apples aren't a topic in Quantum Mechanics. You're assuming that the microphysical is all that counts, and everyday objects can be dismissed because physicists in a lab can achieve counter intuitive results with subatomic particles.

So, is it possible on your view that all of your experiences could be hallucinations? If not, why not? — The Great Whatever

By this you mean a BIV type scenario I take it, because it doesn't make sense that our entire life experience could be the ordinary kind of hallucination. As to how the direct realist is able to make a metaphysical distinction between hallucinations or dreams and veridical experiences, wouldn't that be a matter of inference to the best explanation amongst a life worth of experiences? Maybe when I saw a ghost I thought it was a real experience, until later when I realized that my mind was playing tricks on me.

I think I want to bypass the second one entirely, because the comment was more in passing, and in any case I'm not sure that 'embodied' is anything but a hoo-ha word. The stakes of the argument or what points are to be made are just unclear to me, and I can't see the debate being productive. — The Great Whatever

Embodied cognition emphasizes the role that the kind of bodies we as humans have play in thought, perception, etc. This is in opposition to computationalism and functionalism where the functional or computational organization is what matters, not the biological substrate. Thus you can have someone like Dennett claiming that if we met a six legged intelligent, arthropod alien which utilized X-Ray version, we wouldn't have any fundamental difficulties in communicating with them.

As to the argument at hand, functionalism and computational theories of mind are at home with talk of representations and constructing perception, while embodiment would focus on how perception is part of an organism's ability to maneuver in their environment.

I'm not saying that the micro-physical is all that counts and that everyday objects can be dismissed. I'm saying that for direct realism to work with quantum mechanics it would require that we see the world as waves and particles and fields and whatnot. It's for the very reason that we don't see the world like this that direct realism fails and indirect realism is a more plausible account of perception (which, incidentally, is why indirect realism is the accepted view in the natural sciences).

Furthermore, I'm rejecting @Aaron R's claim that if the things we take ourselves to be perceiving are unlike the things that explain the perception then the things we see are fake. The apple I take myself to see is very unlike the electromagnetic radiation and subatomic particles that explain the act of seeing but it is still the case that the apple I see is real.

But the apple you take yourself to perceive is not just the electro-magnetic radiation and subatomic particles that you claim "explains" the perception. I tend to think that neither perception nor apples can be fully explained in those terms; that's the reductionism I reject.

I'm still not sure what it could even mean to say that a perception is veridical while at the same denying that anything like the ostensible object of perception actually exists. That seems incorrect almost by definition.

But the apple you take yourself to perceive is not just the electro-magnetic radiation and subatomic particles that you claim "explains" the perception. — Aaron R

That's why your claim that "If [something] is deemed to be fake, it will ultimately be deemed so on the basis of some story about how our sensory apparatuses are not causally related to anything like the objects we take ourselves to be perceiving" is wrong. The apple is real but the apple I take myself to be perceiving is not like those things to which our sensory apparatuses are causally related (i.e. electromagnetic radiation and subatomic particles).

I'm still not sure what it could even mean to say that a perception is veridical while at the same denying that anything like the ostensible object of perception actually exists. That seems incorrect almost by definition.

I'm not saying that the object doesn't actually exist. I'm saying that a description of the apple as we perceive it is not a description of whatever mind-independent things explain the occurrence of such a perception. Therefore direct realism fails. The fact that the descriptions are different is why indirect realism is a more accurate account of perception.

I'm saying that a description of the apple as we perceive it is not a description of whatever mind-independent things explain the occurrence of such a perception. — Michael

I am saying that there's no good reason to believe this insofar as there's no good reason for accepting the reductionism on which it is based.

I am saying that there's no good reason to believe this insofar as there's no good reason for accepting the reductionism on which it is based. — Aaron R

Of course there are good reasons to believe this. We describe an apple as round and hardish and red and sweet. But this isn't how we describe the mind-independent things that explain the occurrence of our perception. To think that when we see red or taste sweetness that this redness and sweetness are inherent properties of these mind-independent causes is evidently false. Redness and sweetness are experiences produced by brain activity in response to certain stimulation. It's not that we encounter the redness and sweetness that was already present prior to the seeing and the tasting. That's why direct realism fails.

To think that when we see red or taste sweetness that this redness and sweetness are inherent properties of these mind-independent causes is evidently false. — Michael

Note that colour realism and objectivism are popular views among philosophers.

One of the most prominent views of color is Color Objectivism, i.e., the view that color is an objective, i.e., mind-independent, intrinsic property, one possessed by many material objects (of different kinds) and light sources. — SEP

http://plato.stanford.edu/entries/color/

Can one experimentally show that there are objective colours?

1) I can tell the difference between veridical and non-veridical experience.

2) I cannot tell the difference between veridical and non-veridical experience.

You cannot claim both of these. The skeptic has nothing to do with it; you can't blame him.

Inference to the best explanation is only a coherent option when there is evidence that could possibly bear on the matter, which the direct realist's position is forced to rule out.

I can't resist jumping in here because it seems to me you are misrepresenting jamalrob's argument so egregiously.

It should be (and jamalrob may correct me on this):

1) I can tell the difference, for the most part. between veridical and non-veridical experience.

2) I cannot always tell the difference between veridical and non-veridical experiences.

No contradiction.

1) I can tell the difference, for the most part. between veridical and non-veridical experience.

2) I cannot always tell the difference between veridical and non-veridical experiences. — John

More like:

1) I can tell the difference between vertical and non-verdical experience. It is given in experience which is distinct from the immediate sensation of an object-e.g. Seeing the presence of a tree (makes no comment on whether it is really or virtual) and then a different experience about he nature of the tree (e.g. "that tree is real" or "that tree is virtual" as the case may be).

2) I cannot tell whether an object is real or virtual from its immediate sensation. When I only have this, when I do not have experience of whether am object is real or virtual, I do not know whether or not the sensation I have is of a real or virtual thing.

Notice that 1) is impossible if the two are phenomenologically indistinguishable. If for any particular case I cannot tell, then it cannot be that I can tell for the most part (or in other words, there is no way by his own criteria to tell whether or how often I can tell or not). So whether or not jamalrob wants to say this (perhaps he does), he can't.

It seems to me the whole argument between Direct and Indirect Realism is based on a kind of category error.

Direct Realism is correct logically and phenomenological speaking. When I see a tree, I see a tree not a mental representation of a tree.

Indirect Realism is based on a scientific understanding and description of the physical and physiological processes of perception, which are quite complex. In this context it makes sense to say that perception is a mediated process. The claim about the indirectness of perception, which is inflated to the position of Indirect Realism, is read into, and extrapolated out of, the "mediate" (i.e. not immediate or direct) in 'mediated process'.

The argument is based on fallacious understandings of conflict between to two that come about due to inappropriate attempts to merge the two interpretative contexts.

Can one experimentally show that there are objective colours? — Michael

Yes. In any instance where a person sees a colour in response to an object, an objective colour is shown: it is true that the object in question has the relevant colour. This effect is then repeated when the person again sees the object. In this respect to is no different to something like object's shape (or any other part of the object), which is similarly shown through body produced experience.

Recognizing a tension in your thought is not fallacious. There is in fact such a tension; the modus operandi for the direct realist is to cover his ears, but why should it be?

I don't agree. Our ability to tell is not merely phenomenological it is also based on the whole accumulated logic of intersubjective experience, including a coherent and consistent body of scientific understanding..

Also we can tell, phenomenologically speaking, not necessarily from within the experiences, but by the transitions from one kind of experience to the other. So, for example, when I wake up, I realize "Oh, that seemed so real, but it was just a dream". This is a pretty universal kind of experience.

The phenomenon of lucid dreaming also shows that we are in fact sometimes capable, phenomenologically, of telling the difference from within the experience itself. Lucid dreamers commonly report that once they realize they are dreaming they are then able to 'direct the dream' however they want to.

Indirect realism merely strawmans direct realism. It falsely thinks direct realism is arguing perception just appears without any causal system, without any system of interaction within the body,without any sort of meditation between the existing object and experience.

This is, of course, not true. And something the direct rats has not argued. Each instance of perception is created out of system which shows only shows specific aspects of an object in question. What is perceived of an object (and which objects are perceived) is meditated by the body and what is present in the environment.

Indirect realism misreads the focus of the direct realist argument, how the meaning of things is what is experienced when they are perceived, for an argument about how experiences are caused.

Yes, I agree, and that is just what I was alluding to.