Well said.

Our periphery is quite limited, so one can at least understand the indirect realist’s skepticism. The body is no doubt a mystery for any organism that cannot see its own ears, let alone what occurs beneath the epidermis. Introspection and wondering could never penetrate its own depths. But I think we’ve taken enough looks inside to realize there are no spirits pulling on strings in there.

As for animals, their bodies are different. What else is there to say? We can say a dog has different perceptions, experiences, phenomena, fine, but that’s multiplying zeroes. Their bodies are the only thing that differs from us. Their relationship to everything else can be described in the exact same manner as ours: direct, without any specious intervening factors.

And here's the reason this topic is recalcitrant. Both sides describe the situation in almost the same terms, but mean slightly different things in each case, talking past each other using much the same language. — Banno

I make much the same point every time this discussion happens. My earlier comments here and here get to the heart of the issue.

Arguing over whether we see external objects or see some mental image of external objects doesn't address the epistemological problem of perception. The concern is the relationship between the phenomenology of experience and the mind-independent properties of external objects.

According to (phenomenological) direct realism, I see the apple to be red because colour primitivism is the case, and when I see the apple its mind-independent properties are actually present in my experience.

According to indirect realism, I see the apple to be red because its mind-independent properties are such that it reflects light with a wavelength of ~700 nm, and light at that wavelength, when stimulating my eyes and central nervous system, triggers the experience of the colour red -- and this redness is a property of my experience, not a property of the apple (much like pain is a property of my experience, not a property of the fist that hits me). Redness is a "mental representation" of a surface that reflects light at a particular wavelength.

The direct realist says that seeing is constructing a model of the tree. The process of construction is part of the "self" doing the seeing. — Banno

In fact I think this is a prime example of the problem. The indirect realist will agree with this, and say that this model is a representation of the tree, and that it is this model that (directly) informs our understanding. You appear to be describing indirect realism, but calling it direct realism.

Arguing over the semantics of whether this should be called "seeing a tree" or "seeing a model of a tree" is a red herring. It's like arguing over whether I'm talking to my parents (over the phone) or talking to my phone, or arguing over whether I feel the fire or feel the burning pain in my hand. They're just different ways of talking that make no real difference to the underlying philosophical consideration.

We are not little homunculi driving robots and looking at screens. We are members of a community who live embedded in a shared world within and with which we collectively interact. — Banno

If a 'person' is taken as referring to a brain, and only to a brain, then a person is by definition a homunculus , hence a forteriori, a subject of indirect realism. Community interaction among brains cannot change this conclusion.

Irrealism tries to sidestep the dispute by claiming in a relativistic and solipsistic fashion, that direct-realism only applies in the first-person, i.e that only the first-person isn't a "brain person".

I do see that they're both flawed. Do you mean that this leads to idealism? — frank

Where else are you going to turn to get principles for understanding the reasons for these flaws?

it would be really helpful if people would state what definition of "direct realism" and "indirect realism" they are using when they are posting. — prothero

Direct realism: Reality includes sensitive beings, and sensible objects, amongst, and consisting of a load of insensible stuff like radio waves, molecules, and the core of the earth. Sensitive beings include dogs, rabbits, and blind, colour-blind, and shortsighted humans. Sensitive beings can sense sensible objects in various ways. A blind man can tell a golden delicious from a mackintosh red by the feel, the smell and the taste. I can tell the difference by the colour.

One does not see "the look of the apple", but the apple.

"The look of the apple" is an abstraction, a memory, an image one might recall with more or less detail according to artistic talent and training, peculiarities of vision, or whatever. One represents an apple in "the mind's eye", or on paper with a pencil, and associates it with the shape of the written word. This is easier said than done.

The apples posted to this thread are mere visual likenesses, which the sighted among us can recognise, (cognise again), because we are already, directly familiar with real apples. Just as we read what is said because we are already familiar with the language in written form. An infant does not have a visual image of an apple, but will happily eat stewed apple. A little later we will look together at My First Alphabet, at the picture of an apple, and pretend to eat it. Because a child of one already knows the difference between the likeness of an apple and an apple. It's a fine joke to pretend not to.

it would be really helpful if people would state what definition of "direct realism" and "indirect realism" they are using when they are posting. — prothero

I'll take a rather simple definition from the problem of perception:

In the context of the Problem of Perception, these cases are usually distinguished as follows: a veridical experience is an experience in which an ordinary object is perceived, and where the object appears as it is; an illusory experience is an experience in which an ordinary object is perceived, and where the object appears other than it is; a hallucination is an experience which seems to the subject exactly like a veridical perception of an ordinary object but where there is no such perceived or presented object.

The direct realist view is the view that things are as they appear. Directness is their explanation of how this is the case. It is how they resolve the epistemological problem of perception. Things appear as they are because perception is direct.

The indirect realist view is the view that things might not be as they appear. Indirectness is their explanation of why this is the case. It is why there is an epistemological problem of perception. Things might not appear as they are because perception is indirect.

Semantic direct realism, as Howard Robinson calls it, seems to accept the indirect realist's view that things might not be as they appear, but wants to call this direct perception anyway, even though directness was used to explain how things appear as they are.

I really don't care if you want to describe perception as "seeing a tree" or "seeing the appearance of a tree". It makes no real difference. The relevant fact is that an object's appearance is not its mind-independent nature, and that it is an object's appearance rather than its mind-independent nature that is the direct object of rational thought, and so there is an epistemological problem of perception. Seeing something might not show us what it’s like when we don’t see it. And I think modern science has proven that things aren't as they appear.

They're just different ways of talking that make no real difference to the underlying philosophical consideration. — Michael

:up:

Where else are you going to turn to get principles for understanding the reasons for these flaws? — Metaphysician Undercover

Can you tell me the reasons for the flaws?

But for indirect realism, what everyone sees is some private mental image, and hence what you see and what the other person sees are quite different. — Banno

Almost, in that my private perception of a tree may or may not be the same as anyone else's, but it is impossible to know, as it is a private mental image.

Wittgenstein Philosophical Investigations may be used to give insights into Indirect Realism, including his strong case against the possibility of a private language and his arguing that nobody knows another person's private sensations.

The Indirect realist accepts Wittgenstein's conclusion that one's private perception of an object, such as a tree, is forever unknown to anyone else.

The Direct Realist doesn't accept Wittgenstein's conclusion. The Direct Realist argues that we perceive objects in the world as they really are, immediately and directly. Therefore, if two people are looking at the same object in the world, such as a tree, as both will be perceiving the same object in the world immediately and directly, their private mental images will be the same, meaning that each will know the others private sensations.

Therefore, whether one is an Indirect or Direct Realist depends in part of whether one accepts Wittgenstein's Philosophical Investigations

If indirect realism were taken at face value, two people cannot both look at the same thing — Banno

Wittgenstein's para 293 in Philosophical Investigations about a beetle in a box provides a solution to the problem raised about Indirect Realism, ie, how is communication possible between people using a public language when nobody can know another person's private sensations.

For example, as an Indirect Realist, my private mental image of a tree may be different to everyone else's, yet I can use use the word "tree" in a social language game with others. Within the language game, the word "tree" isn't describing my mental image, as each particular mental image has dropped out of consideration within a language game as irrelevant.

Wittgenstein's beetle in the box explains the connection within Indirect Realism between private mental images and a public language.

The indirect realist says what one sees is the model of the tree — Banno

As an Indirect Realist, I am not saying that I see a model of a tree, I am saying that I directly see a tree, though the tree I see is an indirect representation, image or model of something that exists in the actual world.

A key concept is intentionality, in that my mind is directed at the tree that I perceive, not in virtue of the tree representing another object, another tree, as this would lead into an infinite regression and the homunculus problem.

I am saying that I directly see a tree, though the tree I see is an indirect representation, image or model of something that exists in the actual world — RussellA

So, for you, the eyes are not involved in seeing. A blind man can see?

I think modern science has proven that things aren't as they appear. — Michael

Surely things must appear to the scientists to be the way they now report them to be; otherwise why are they reporting them to be that way?

Things are not as they once appeared.

As an Indirect Realist, I am not saying that I see a model of a tree, I am saying that I directly see a tree, though the tree I see is an indirect representation, — RussellA

What about the tree that you climb? Is that a representation?

So, for you, the eyes are not involved in seeing. A blind man can see? — Isaac

I see what you mean. I see the reason for your post. I see the relation between the eyes and what is seen. I see trees in my dreams. A fool cannot see beyond the end of their nose. I see trees in my hallucinations. I see myself on holiday. I see the light at the end of the tunnel. A blind man can see the truth. A blind man can see where they went wrong. A blind man can see the error of their ways.

Yes, a blind man can see.

Surely things must appear to the scientists to be the way they now report them to be; otherwise why are they reporting them to be that way?

Things are not as they once appeared. — Isaac

I meant specifically that things aren't as they appear to ordinary human perception, e.g. that objects aren't coloured, in the colour primitivist sense that was believed by direct realists. Objects only appear coloured because of the way the human body responds to stimulation by electromagnetic radiation.

a blind man can see. — RussellA

But can they see trees?

I see trees in my dreams... I see trees in my hallucinations. — RussellA

Do you?

Leaves fall from trees in autumn. Do leaves fall from what you see in your dreams and hallucinations?

I can build furniture out of fallen trees. Can I build furniture out of what you see in your dreams and hallucinations?

And what could "I thought I saw a tree, but I was wrong" possibly mean in your world?

How could one ever be mistaken about what one sees?

I meant specifically that things aren't as they appear to ordinary human perception — Michael

You're assuming that things can only rightly be one way. Is that an assumption you can justify? Can an apple not be both red and 'reflective of 400nm wavelengths'?

Can an apple not be both red and 'reflective of 400nm wavelengths'? — Isaac

I'm not saying anything about what they can or can't have. I'm saying something about what they do and don't have. And there's no indication that an apple has anything like a sui generis property of "redness", equivalent to a red appearance. The evidence is just that objects reflect light at certain wavelengths, and that when light with a wavelength of 700nm stimulates the eyes of the typical human then the object appears red to that person (and when it stimulates the eyes of the atypical human then the object appears orange, or green, or whatever to that person).

It's a mistake to then project this coloured appearance onto the external world. It's the naive view that modern science has refuted.

What about the tree that you climb? Is that a representation? — unenlightened

I know that I perceive something and I know that this something has the name "tree".

As I innately believe in the law of causation, in that every effect has a cause, I therefore believe that there is something that has caused me to perceive a "tree". I don't know what this something is, but I do believe it exists.

As language doesn't exist in the absence of sentient beings, the something in the world that we call a "tree" cannot be a "tree", as "trees" only exist within human language. "Tree" as a word in human language represents something else.

Therefore the "tree" that I climb as a word is a representation of something else but the something else that has caused me to perceive a "tree" isn't a representation.

It's a mistake to then project this coloured appearance onto the external world. — Michael

That's what I'm enquiring about. Why is it a mistake? If an object can have the property 'reflects light with a wavelength of 700nm' why can't we call that property "red"?

Why is it a mistake? If an object can have the property 'reflects light with a wavelength of 700nm' why can't we call that property "red"? — Isaac

You can call it anything you like. But it would be fallacious to conflate redness in this sense with redness as the appearance. We'll just be using the word "red" to mean two different, albeit causally connected, things.

it would be fallacious to conflate redness in this sense with a red appearance. — Michael

It would indeed since a 'red appearance' is utter nonsense.

It would indeed since a 'red appearance' is utter nonsense. — Isaac

You don't think that apples appear to be red?

But can they see trees? — Isaac

According to Do blind people dream in visual images?, yes.

Instead, scientists have performed brain scans of people blind since birth while they are sleeping. What scientists have found is that these people have the same type of vision-related electrical activity in the brain during sleep as people with normal eyesight. Furthermore, people blind since birth move their eyes while asleep in a way that is coordinated with the vision-related electrical activity in the brain, just like people with normal eyesight. Therefore, it is highly likely that people blind since birth do indeed experience visual sensations while sleeping. They just don't know how to describe the sensations or even conceptually connect in any way these sensations with what sighted people describe as vision.

:up:

You don't think that apples appear to be red? — Michael

I don't think there's such a thing as a 'red appearance'. Apples appearing red, just means that I think apples are red. My estimate is that they're red. I'll reach for the word "red" to describe them...etc. There's no separate thing 'the appearance of red' with which we might mistake the property of the apple.

According to Do blind people dream in visual images?, yes. — RussellA

So I can make furniture out of what blind people are seeing?

What about the tree that you climb? Is that a representation? — unenlightened

Not in the context of the standard narrative. I guess people will divide off according to what they think of the stories we tell: are they metaphors as Nietzsche suggested? Or would you agree with Sartre that you are the situation? Or perhaps a non-philosophical, folkways rendition is better?

I don't think any of these questions are directly related to how we perceive the world and ourselves. Maybe indirectly?

Apples appearing red, just means that I think apples are red. — Isaac

There's more to experience than just rational thought. Seeing and feeling and tasting aren't just cases of thinking.

But what does it mean to think that apples are red? You suggested before that to be red is to have a surface that reflects light with a wavelength of 700nm, so to think that apples are red is to think that apples have a surface that reflects light with a wavelength of 700nm? How does that make sense given that people saw, and thought, that apples were red long before they even had the concept of electromagnetic radiation?

There's no separate thing 'the appearance of red' with which we might mistake the property of the apple. — Isaac

You think that they're red because they appear red. You "reaching" for the word "red" to describe apples isn't just something that happens in a vacuum. And presumably you're not a p-zombie that just mindlessly responds to stimulation by spouting out words.

I can build furniture out of fallen trees. Can I build furniture out of what you see in your dreams and hallucinations? — Isaac

You can build furniture out of the something in the world that has caused me to perceive a tree providing this had been a veridical experience, but not if a dream or an hallucination.

How could one ever be mistaken about what one sees? — Isaac

One can never be mistaken about what one sees. If you see a tree, it is absolutely certain that you have seen a tree. If you see a unicorn running through Central Park, it is absolutely certain you have seen a unicorn running through Central Park.

However, one can be mistaken in one's belief whether it was a veridical experience, a dream, an illusion, a film or an hallucination.