It's obviously somewhat different than the appearance, or naive realism would have gone unquestioned. — Marchesk

It doesn't follow from the statement "We've been mistaken about some things" that we've been mistaken about everything. It does not follow from the statement "We do not see some things as they are" that we cannot see anything as it is.

Who's arguing for naive realism?

Explanation is always complete because it details some thing-- "It has been explained"-- but never exhaustive because there are things of which a given account does not speak.

So yes, the tree has been accounted for, insofar as it has been truthfully spoken about. Speak the shape.of it's leaves, you give a full account, insofar as you describe, the shape of the trees leaves. Do not be fooled by the fact there is much more to the tree, you have genuinely accounted for the tree. You just aren't accounting for the many other ways and relations this tree exists in.

It's obviously somewhat different than the appearance — Marchesk

Set it out... this difference between world and.... what, exactly are you claiming must be different than the world?

Our image... as retinal?

Seems to me like we do not subject accounts we know to be perception to a supposition of it being an illusion... so I suspect we might be closer to the naive realists than you might think.

Who's arguing for naive realism? — creativesoul

Sometimes the ordinary language approach seems to be defending a version of naive realism. The point is that we can't just say the world is how we perceive and think it and leave it at that. It's certainly not enough to say that ordinary word usage captures reality.

Set it out... this difference between world and.... what, exactly are you claiming must be different than the world? — creativesoul

Our experience of the world including perceptions and thoughts.

Our image... as retinal? — creativesoul

That wasn't my metaphor, but visual perception is part of it.

Explanation is always complete because it details some thing-- "It has been explained"-- but never exhaustive because there are things of which a given account does not speak.

So yes, the tree has been accounted for, insofar as it has been truthfully spoken about. Speak the shape.of it's leaves, you give a full account, insofar as you describe, the shape of the trees leaves. Do not be fooled by the fact there is much more to the tree, you have genuinely accounted for the tree. You just aren't accounting for the many other ways and relations this tree exists in. — TheWillowOfDarkness

Not much to say aside from we're working from incommensurate notions of what counts as "complete". An incomplete account can be true. I agree. I do not ever call an incomplete account of X a full account of X.

Our experience of the world including perceptions and thoughts. — Marchesk

So, there's clearly a difference between the world and our thought and belief about it?

I agree.

Seems to me like we do not subject accounts we know to be perception to a supposition of it being an illusion... so I suspect we might be closer to the naive realists than you might think. — TheWillowOfDarkness

Well, with vision we see solid objects and not the mostly empty space they're made of, or all the EM radiation passing through them. We see them as colored. And we seem them from a certain location happening over a certain time interval we can experience (so not nanoseconds).

So that image (or sequence of images) is not exactly what an object is.

It's certainly not enough to say that ordinary word usage captures reality. — Marchesk

So, don't say that...

See how easy it is to solve some of these historical problems of language use? Language use is not the sort of thing that captures anything. Some things we talk about aren't even things that are capable of being "captured" to begin with... we talk about them nonetheless...

So, there's clearly a difference between the world and our thought and belief about it? — creativesoul

Also between our perception of the world and how it is. Science tells us this in a thousand ways.

Yes, basically that's it, although the visual metaphor bothers me a little, because one might argue we're being fooled by thinking only in terms of vision, where illusions can occur. — Marchesk

Yes illusions can occur in all of perception, not just vision, by the word "see" I was referring to the whole of perception not just what we see when we open our eyes.

Terrapin Station (who is now banned, unfortunately, even though he was sometimes hard to discuss with I believe he has interesting things to say), considered that each individual perceives the world as it really is from their own point of view, from their own reference point, I believe that's true if properly interpreted, I wanted to discuss that more completely with him but I never got around to doing it.

That is, even if an individual doesn't perceive the world as it really is, what the individual perceives is influenced by some real things that influence his perception, so the individual perceives what the world really is like when these real influences are taken into account, but the thing is of course the individual doesn't perceive these real influences as long as they mess with his perception.

P3) It is neither self-evident nor certain that “the being of X is independent of its being known.”
C2) Therefore, philosophy should not begin with the assumption that “the being of X is independent of its being known.” — PessimisticIdealism

Again you are making the same mistake. That a proposition isn't certain is not a reason to assume its negation.

It doesn't follow from the statement "We've been mistaken about some things" that we're been mistaken about everything. It does not follow from the statement "We do not see some things as they are" that we cannot see anything as it is. — creativesoul

That's not what I said either, I said we cannot all be seeing things as they are (otherwise there would be no disagreement), and I also said we cannot be mistaken about everything, for instance we cannot be mistaken about the fact that "not everything can be an illusion, there has to be something real".

That is, even if an individual doesn't perceive the world as it really is, what the individual perceives is influenced by some real things that influence his perception, so the individual perceives what the world really is like when these real influences are taken into account, but the thing is of course the individual doesn't perceive these real influences as long as they mess with his perception. — leo

That makes sense. But then when the individual wants to know what the world's like independent of anyone perceiving it, questions about realism, epistemology and science come into play. And they might want to know this because they think there is a world that's more than just humans perceiving it.

So for example if the individual wishes to know how humans came to be, they have to go beyond human perception to an explanation that gives rise to our individual human perceptions.

That makes sense. But then when the individual wants to know what the world's like independent of anyone perceiving it, questions about realism, epistemology and science come into play. And they might want to know this because they think there is a world that's more than just humans perceiving it. — Marchesk

Yes, but maybe the question "what the word really is independent of anyone perceiving it" is meaningless, maybe there has to be some being in order for there to be a world. I find it increasingly hard to conceive of a world devoid of beings from which beings arise. If there was a world that existed before beings and that behaved according to Laws, what made the things follow these Laws? The only evidence we have is that change occurs because of a will, when we will something we cause change to occur, we have no evidence that things change because they follow Laws independent of a will, that's an unsubstantiated postulate of modern science.

It doesn't follow from the statement "We've been mistaken about some things" that we're been mistaken about everything. It does not follow from the statement "We do not see some things as they are" that we cannot see anything as it is.
— creativesoul

That's not what I said either, I said we cannot all be seeing things as they are (otherwise there would be no disagreement), and I also said we cannot be mistaken about everything, for instance we cannot be mistaken about the fact that "not everything can be an illusion, there has to be something real". — leo

We're in agreement, it seems...

I can accept that something external exists, but the question is if the everyday things we talk about are reducible to those external things. Does a word like “Everest” simply ‘pick out’ a particular collection of matter? Is that all there is to reference? I don’t think so. I offered the example of Theseus’ ship: the material that leaves is not the material that returns, but it’s nonetheless the same ship, and so there’s more to Theseus’ ship than its material. And as you accept, nature doesn’t draw lines. There’s no objective measure that determines that this rock is part of Everest and that this nearby rock isn’t. There’s no objective measure that determines that this bunch of matter counts as a single object at all.

So you can talk about things like electrons and photons existing independently if you like, but as soon as you start talking about the macroscopic objects of everyday life then I think a realist analysis starts to fall apart as reductionism isn’t tenable.

As for the skeptical alternative, that would require a clear definition of what it means to know anything — Harry Hindu

Well yeah, they're realists about other minds. Which is open to the same sort of criticism of the OP — Marchesk

Yes. Doesn't that tie into the OP's argument? — Marchesk

The burden of proof lies on the realist to demonstrate that he “knows” whether the being of X is independent (not in terms of relations (i.e. the being of X ceases to partake in the relation of being known to a knower")) of its being known — PessimisticIdealism

I'm not quite clear on what the problem is. Don't we acquire knowledge from observations? We don't know anything until we observe it. So the answer is observe it and then you will know.

Are you asking how do we know things independent of knowing? That would be a silly question.

When you observe your experiences it seems pretty clear that there is an external world because it would be a different experience if there wasn't. You might say that there'd be no experience at all.

If there wasn't an external world, "knowing" wouldn't make any sense. "Mind" wouldn't make any sense. The existence of "words" wouldn't make any sense, nor would how they came to exist in the first place.

When you observe your experiences it seems pretty clear that there is an external world because it would be a different experience if there wasn't. You might say that there'd be no experience at all. — Harry Hindu

But that external world might be a brain in a vat, a simulation, a dream in God's mind, etc. if we take into account skeptical possibilities.

I'm not quite clear on what the problem is. Don't we acquire knowledge from observations? We don't know anything until we observe it. So the answer is observe it and then you will know. — Harry Hindu

The problem is that our acquisition of knowledge doesn't lead to certainty. Which is usually fine for everyday living, but has issues when doing philosophical inquiry. If we want to know what's real, then we have to deal with skepticism.

But that external world might be a brain in a vat, a simulation, a dream in God's mind, etc. if we take into account skeptical possibilities. — Marchesk

But those are all external worlds. Is the argument "how do we know there is an external world", or "how do we know what the external world is like"? The latter assumes the prior is true.

The problem is that our acquisition of knowledge doesn't lead to certainty. Which is usually fine for everyday living, but has issues when doing philosophical inquiry. If we want to know what's real, then we have to deal with skepticism. — Marchesk

Then the question is how can we be certain, not how do we know things?

How can you be certain that you will never be certain? If you can be certain that you aren't certain, then you're certain about something, right? So it seems that knowledge can lead to certainty?

Then the question is how can we be certain, not how do we know things? — Harry Hindu

Well, that depends on whether knowledge requires certainty.

I think our understanding of knowledge, which leads to paradoxes like, "knowing that you don't know anything" needs to be reworked before we start asking how we can know what the external world is like.

We know what the external world is like by observing it. Asking what it looks like independent of observing it is silly. If you want to know what it looks like, look at it. If you want to know what it is, look at it.

Observing is a causal process. The perceived is one of the causes. Light is another. Your visual system is another cause that leads to the effect of it appearing in your working memory. If you want to know specifically about the thing and not about light or your visual system, then you parse that information in working memory to exclude those causes so that you can get the object being perceived. Your doctor gets at the state of your visual system by asking you to look at an eye chart.

The apple isn't red, that is a product of your visual system and light. What the object is is something that reflects certain wavelengths of light and absorbs others. It does so based on it's ripeness. Ripeness is a property of the apple, not the light or my visual system. I use the information in my working memory to get at the ripeness of the apple so that I may use that information when I am hungry.

“Are you asking how do we know things independent of knowing? That would be a silly question.” — Harry Hindu

It is indeed an absurd question; however, the question is simply a response the absurd statement “knowing makes no difference to what is known.” In order for the realist’s claim to have any meaning, he must know that which he defines as unknown. In other words, he claims to have knowledge about that which he cannot—by his own definition—have knowledge about. He can’t support his claim by relying on his experience of “knowing x” because said experience would fall under the condition of “x being known;” it is impossible for him to prove that “knowing makes no difference to what is known” unless he takes it as gratuitous. With the development of quantum mechanics, we know that observation or measurement does in fact alter the being of an object—take Schrödinger’s Cat as an example. Therefore, if the realist takes “the being of X is independent of its being known” or “knowing makes no difference to what is known” as simply a “given” on faith. With that being said, the realist’s position is undermined by groundbreaking discoveries in the field of quantum mechanics which subsequently serve as evidence that go against the realist’s assertion that “knowing makes no difference to what is known.”

With that being said, the realist’s position is undermined by groundbreaking discoveries in the field of quantum mechanics which subsequently serve as evidence that go against the realist’s assertion that “knowing makes no difference to what is known.” — PessimisticIdealism

Yeah, but that doesn't apply to the macroscale.

I found an interesting statement by Einstein related to this:

"The physical world is real." That is supposed to be the fundamental hypothesis. What does "hypothesis" mean here? For me, a hypothesis is a statement, whose truth must be assumed for the moment, but whose meaning must be raised above all ambiguity — Andrew M

That's basically Kant's synthetic a priori (aka: all events must have a cause).

I wonder, what does the realist say about abstracts/mathematics; is it something human's created, or did it always exist and we just uncovered/discovered its truth... ?

the absurd statement “knowing makes no difference to what is known.” — PessimisticIdealism

You grandparent was born that year.
How does you knowing or not make any difference to that?

This argument is based on a similar argument belonging to Robin George Collingwood. — PessimisticIdealism

Got a reference for that? Would be quite interested in looking it up. Thanks.

Well, unfortunately, you are interpreting the standard realist position wrongly. — PessimisticIdealism

If, in your reading, the 'standard realist position' turns upon nothing other than the contradictory dicate to both know and not know X at the same time, it's far more likely that you've simply vulgarized the 'standard realist position' beyond all sensible recognition.

The basic mistake of objections like yours is to think, mistakenly, that a claim about the mind-indepedence of things is about things, and not a claim about the mind. It's an easy enough mistake to make insofar the grammar of a statement like 'X is indepedent of the mind' puts 'X', the 'thing', in the position of the grammatical subject of the proposition. But such a claim is equally, if not entirely, about the 'mind' and not things.

You can bring this out if you swap subject and object: "Mind is entirely irrelevant to the being of things" (incidentally, the null hypothesis, the onus of which it is the idealist's to disprove). This is just as much the realist's claim, and it doesn't require one jump though the concocted logical hoops of the OP which simply builds contradiction into the premises in order to smuggle it into the conclusion.

Mt. Everest existed in it's entirety regardless of whether or not one believes that. — creativesoul

You simply assume that it does. It would have been more open-minded to have written: "Mt. Everest existed in it's entiretyor not regardless of whether or not one believes that."