But what is the status of this 'only'? Only, as opposed to what, exactly? A thing's appearance is not... nonsense? — StreetlightX

As opposed to the direct realist's (wrongful) claim that a thing's appearance is an objective property that the object retains even when not being looked at.

But that's not a sensical claim. It is not even wrong. It's a grammatically correct salad of words.

Make up your mind: does science 'extract properties which aren't creature dependant' or is science 'creature dependent'. You can't have you cake and eat it. — StreetlightX

Science attempts to be creature independent, and describe the world as it is. That's why we arrive at theories like QM.

And what does this have to do with perception? Jesus.

But that's not a sensical claim. It is not even wrong. It's a grammatically correct word salad. — StreetlightX

But it's not. I have no problems understanding it.

And what does this have to do with perception? Jesus. — StreetlightX

How the fuck do you think scientists came up with a theory of QM? By sitting in their armchairs and dreaming it up? Or running a shit ton of experiments and trying to make sense of them?

Then you have a poor grasp of the English language.

Then you have a poor grasp of the English language. — StreetlightX

I didn't come up with the direct/indirect realism debate, so what you're really saying is that professional philosophers who think it's meaningful don't have a good grasp of the English language.

Correct.

Correct. — StreetlightX

That's a cheap way to dismiss a philosophical issue. But whatever.

But that's not a sensical claim. — StreetlightX

I think you're being pedantic. You can re-read my account of indirect realism without including the word "only": "the indirect realist says that a thing's appearance is representative of its objective properties".

Well if you can make sense of what a thing looks like when there is no looking involved, then be my guest.

And what would 'objective' here mean? After all, there is an objectivity to looking itself, which is what studies of illusion show us.

And what would 'objective' here mean? After all, there is an objectivity to looking itself, which is what studies of illusion show us. — StreetlightX

Objective would mean the properties that give rise to the experience. This would be the properties of the external inputs.

Well if you can make sense of what a thing looks like when there is no looking involved, then be my guest. — StreetlightX

On the direct realist account, perceived objects would have the same properties when nobody is perceiving them. I can't fully buy into this, because it's clear to me some properties are dependant on the perceiver. But some are clearly not.

And what would 'objective' here mean? After all, there is an objectivity to looking itself, which is what studies of illusion show us. — StreetlightX

Properties that things have when we're not looking. As an example, and assuming scientific realism, the charge of an electron or the mass of an atom or the wavelength of a photon would be objective properties.

On the direct realist account, perceived objects would have the same properties when nobody is perceiving them — Marchesk

But we're not taking about 'properties' in the abstract. We're talking about perceptual properties, which, by definition, are related to a perceiver. Again, you're confusing the one with the other.

On the direct realist account, perceived objects would have the same properties when nobody is perceiving them. — Marchesk

What does it mean for a thing to have certain properties when noone is looking at it? I can and I will give you my answer. But I am interested in yours.

What does it mean for the sky to be blue when you're not looking at it?
What does it mean for a wheel to be circular when you're not looking at it?

For example, right now, I'm in my apartment. From this position, I cannot see the color of the sky. Nonetheless, I am of the opinion that the color of the sky, at this very point in time when I am not looking at it, is blue. What does that mean? What am I trying to say? Clearly, I do not know what's the color of the sky at this point in time because I am not looking at it. How can I know it? The answer is that, although I cannot experience it from this position, I can predict it. And I can do so by applying logic of induction to my past observations. What I really mean when I say that the sky is blue at some point in time when I am not looking at it is that I predict, based on my past observations, that if I went outside of my apartment and looked at the sky precisely at that point in time that I would see a sky that is blue. That's all it means. Phenomenalists such as Ernst Mach call this "potential experience". That's what is meant when people say that things exist or have certain properties when we're not looking at them. It does not mean anything more than that. Unfortunately, many people, I am pretty sure you among them, are not willing to accept this description. Why is this so?

But we're not taking about 'properties' in the abstract. We're talking about perceptual properties, which, by definition, are related to a perceiver. Again, you're confusing the one with the other. — StreetlightX

Are some of the perceived properties also properties of the object being perceived? Locke thought so.

What does it mean for the sky to be blue when you're not looking at it? — Magnus Anderson

It means under certain lighting conditions (it's sunny out), the air molecules scatter light at a wavelength that we see as blue.

Phenomenalists such as Ernst Mach call this "potential experience". That's what is meant when people say that things exist or have certain properties when we're not looking at them. It does not mean anything more than that. Unfortunately, many people, I am pretty sure you among them, are not willing to accept this description. Why is this so? — Magnus Anderson

Because I find it extremely lacking, and it makes science into a fiction. It also means other people are a potential experience.

Because I find it extremely lacking, and it makes science into a fiction. — Marchesk

That's simply what prediction (and also retrodiction) is. It concerns itself with what we did not experience, or at the very least, what is not within our memory. If we experienced everything all at once, and thus knew everything as it is, there would be no need for prediction. There would be no need for thinking, reasoning, intelligence, etc.

It means under certain lighting conditions (it's sunny out), the air molecules scatter light at a wavelength that we see as blue. — Marchesk

That is perfectly compatible with my description.

The issue for direct realism is that we do have visual (and other sensory) experiences independent of perception. This raises the spectre that perception involves a mental intermediary instead of being direct. — Marchesk

I don't want to pretend that I've kept up with the direct realism debate, but I think this would be an issue only if it's assumed that what happens when we hallucinate or dream is exactly what happens when we're not hallucinating or dreaming--if it's assumed, in other words, that when we dream of a tree we're seeing a tree just as we would when wide awake and looking out of a window at a tree. I don't think there's any basis for such an assumption.

We're human beings and, of course, perceive, experience, interact with the rest of the world as human beings would. Does that mean we have "direct awareness" of the "external world" (I think that's direct realism)? Well, I don't think there's a world external to us, as I think we're part and parcel of the world--there's just the world, and we're in it. Regardless though, we have such awareness of the rest of the world as human beings may have given our capacities. That doesn't mean that we aren't aware of the rest of the world, directly or indirectly--we're part of the world. It just means that we are what we are.

I don't want to pretend that I've kept up with the direct realism debate, but I think this would be an issue only if it's assumed that what happens when we hallucinate or dream is exactly what happens when we're not hallucinating or dreaming--if it's assumed, in other words, that when we dream of a tree we're seeing a tree just as we would when wide awake and looking out of a window at a tree. I don't think there's any basis for such an assumption. — Ciceronianus the White

I would say that both when awake and when dreaming the immediate cause of the experience is brain activity (or maybe the experience just is brain activity). The difference is that when awake the brain activity is stimulated by some external stimulus and when dreaming the brain activity is stimulated by some internal stimulus. So the nature of the experience is the same even if the cause is different.

I'm gonna re-post something I did in your previous thread @Marchesk, but will add to it.

This is one of those philosophical issues that I don't see the point in, but I don't think this is because of quietism, rather because I don't really see what's at stake in the issue.

What is a theory of perception? Presumably it's a way of assigning a description to the following kind of event: X perceives Y and set of properties and relations P(Y) influenced or deriving from the set of properties and relations P(X,Y). As an example.

I perceive a cup on my table, it is plain white and filled with coffee.

I (X) perceive a cup ( Y ) on my table ('on my table' is a relation between the cup and the table, a member of P(Y) ), it is plain white (a property of the cup, a member of P(Y)) and filled with coffee (being filled with coffee is another member of P(Y)).

I think any direct realist and any indirect realist would agree that indeed I do see a cup on my table, and that it is plain white and filled with coffee. What matters between them is how to analyse 'I see' in terms of the subject: me, X; the object: Y, the cup. Specifically, what matters are the properties of the relation 'sees' between X and Y. How does it arise? What does it mean for me to see X? What are the relations between the seen object and the object? (representational sense data or identity for indirect/direct examples). Answering these questions gives elements of P(X,Y).

What does a theory that uses sense data or identity as fundamental entities in P(X,Y) achieve? At best a generalized description of what it means to be a sensory object - an element of our perceptual world. Whether it is constituted by sense data or populated by the objects themselves doesn't gives us any information about why the relation between the seen object and the object obtains. We 'see' sense data, we 'see' objects, so what? How can someone learn anything about vision or perception in general - how it works - just by attempting to describe the conditions of access to the sensory object?

Let's take a couple of, very abridged examples, of how to learn something about perception philosophically. In the transcendental aesthetic in Kant's Critique of Pure Reason. It proceeds, abridging a lot, by attempting to found the perception of objects in terms of a mental application of necessary qualities of a sensory manifold. Stuff has spatial extent, stuff persists in time. So then we're left, even if you do not agree with the specific conclusions Kant has, that a perceiving subject conditions the observed objects in some way. Hurrah, we've learned something. How do we condition the objects? Through the application of these constraints to the sensory manifold. What about the 'real' relationship with the object? ... Well, whether Kant's noumenon is given a positive (there's really real stuff underneath our perception) or negative (the noumenon is the name of a conceptual delimiter between the intelligible and the unintelligible), no longer tells us anything about perception, rather about how perception relates to knowing. The latter is still debated within Kant scholarship, the former is well established science at this point.

Another is Husserl, with his idea of 'bracketing','reduction' or 'epoché'. This means, roughly, forgetting the objectivity or veridicality of our experiences and instead attempt to deal with their internal structures and webs of meaning. One way he proceeds is by using his imagination to vary perceived objects in order to filter out their non-necessary properties for being those objects, and thus attempts to derive internal structures to perceptual acts. Great, we can learn something through these descriptions about how we intuit objects and ascertain what they count as or are identified as. Whether the object is 'really there' or 'just a sense object' doesn't matter for the purposes of (transcendental phenomenology) description of perceptual events. If you asked Husserl whether his phenomenology cared about the real existence of objects vs their status as perceptual ideals, he'd probably say something like 'no, I don't want to repeat the errors my method was meant to avoid'.

The debate between direct and indirect realism(s) proceeds after granting people a perceptual world. The next step is for some reason thinking 'how perception works' can be answered through analysis of our condition of access to the already granted perceptual world. How perception works is a question on the level of the manifestation of the perceptual world, not on its conditions of possibility. Is it then surprising that absent from this kind of analysis is any analysis of the performativity in the perceptual event, and this changes the kind of questions that would be asked of a perceptual theory. A contrastive question between direct and indirect realism, of specific sorts, might be 'do I see the cup of coffee or do I see a representational sense datum of the object?', an analysis inspired by the performativity of the perceptual act (it's a verb, c'mooooon) might ask "how is it that I see the coffee cup? what perceptual structures allow me to see the coffee cup?". It changes debates from, ultimately, a semantic theory of perceptual verbs or their conditions of possibility to 'what makes us perceive how we perceive and how do we perceive?'

In terms of the original formulation, the debate between indirect and direct realism does not attempt to flesh out P(X,Y), it instead attempts to look at the conditions for the possibility of P(X,Y) while forgetting that it does this. Is it any wonder that this thread and the previous one are full of unsubstantial semantic dispute, and that any 'evidence' for direct or indirect realism based on the real properties of perception can be interpreted favorably or explained away...

If we already grant the 'world of perception' to a person, what remains is to give an account of its formation and stability rather than our conditions of access to it.

I would say that both when awake and when dreaming the immediate cause of the experience is brain activity (or maybe the experience just is brain activity). The difference is that when awake the brain activity is stimulated by some external stimulus and when dreaming the brain activity is stimulated by some internal stimulus. So the nature of the experience is the same even if the cause is different. — Michael

I find it difficult to accept that we're having the same experience when hallucinating or dreaming that we have when we're not. If that's the case, why would we even speak of hallucinations or dreams? There would be no reason to distinguish them from other experience, and we do. I don't think we distinguish them solely by their causes.

I find it difficult to accept that we're having the same experience when hallucinating or dreaming that we have when we're not. — Ciceronianus the White

It would be different in that it was caused by some external stimulus, but it would be the same in that it emerges from (or is identical to) brain activity.

I don't think we distinguish them solely by their causes. — Ciceronianus the White

How else do we distinguish them? Certainly there's a qualitative difference; experiences caused by external stimuli tend to be far more vivid and regular than experiences caused by internal stimuli (although I've never hallucinated, so I'm not sure what it's like to see things when on drugs or when suffering from some mental illness; my only reference is dreaming).

I find it difficult to accept that we're having the same experience when hallucinating or dreaming that we have when we're not. If that's the case, why would we even speak of hallucinations or dreams? There would be no reason to distinguish them from other experience, and we do. I don't think we distinguish them solely by their causes. — Ciceronianus the White

I agree with Michael. Even if the two experiences, the experience of seeing a tree with your own eyes and the experience of hallucinating a tree, were equally vivid they would still be different because of the context. Letters 'A' and 'A' are equal in the sense that they are both the letter 'A' but they are different in that their position in the sequence of letters that is this sentence is different. Context is extremely important.

agree with Michael. Even if the two experiences, the experience of seeing a tree with your own eyes and the experience of hallucinating a tree, were equally vivid they would still be different because of the context. Letters 'A' and 'A' are equal in the sense that they are both the letter 'A' but they are different in that their position in the sequence of letters that is this sentence is different. Context is extremely important. — Magnus Anderson

I think Michael is saying they are not different.

How else do we distinguish them? Certainly there's a qualitative difference; experiences caused by external stimuli tend to be far more vivid and regular than experiences caused by internal stimuli (although I've never hallucinated, so I'm not sure what it's like to see things when on drugs or when suffering from some mental illness; my only reference is dreaming). — Michael

I'm not sure what you would consider a "difference" in this case, if you maintain that the experience is the same regardless of the differences you acknowledge.

A person sitting with a friend who is hallucinating would probably think there is a difference if that person heard the friend begin to speak to people who weren't there or called attention to a tree if there was no tree. That person would, I think, believe the friend was not seeing a tree or people who weren't there, thereby noting a significant difference between the experience of seeing and the experience of hallucinating. Likewise, if that person's friend said "I had a dream about a tree" I think the person would not think his friend saw a tree while the friend was dreaming.