What does it mean chairs exist because we perceive them? Nobody ever said that. Berkeley said chairs exist because they CAN be perceived. So yes, for something to exist it must be perceiveABLE in some way, even if this is looking through a microscope or performing an experiment.

Chairs exist materially... What does that mean, and how is it any different from chairs existing mathematically? What are the real differences between those two concepts? And please don't answer that chairs are either material or mathematical in different words because im asking you precisely what information you are communicating by saying chairs are mathematical. Otherwise your statements are like me communicating to you that jealousy is pink. That's what your statements mean to me at the moment. Chairs exist materially = jealousy is pink. So Im asking you to explain to me what chairs exist materially practically and actually means. And to do that you need to list differences: for example, what's the difference between pink jealousy and non-pink jealousy? What's the difference between the material chairs and the mathematical chairs?

What's the difference between the material chairs and the mathematical chairs? — Agustino

Material chairs are made up of physical stuff such as atoms and their bonds. Mathematical chairs only have mathematical properties. There is no physical stuff. Surely you've heard of Max Tegmark and his claim that the universe is mathematical. Instead of particles or fields or space being the ontological structure, it's numbers and their relations.

What does it mean chairs exist because we perceive them? Nobody ever said that. Berkeley said chairs exist because they CAN be perceived. — Agustino

Berkeley said "to be is to be perceived". Plenty of people on these forums have argued along those lines. They call themselves idealists or anti-realists, or have you been absent the various idealist/realist debates?

Then how does the realist distinguish between a veridical and a non-veridical experience? — Michael

For example, by verification.

The very principle of realism is that the way the world is is independent of our experiences such that we can see things that aren't there and not see things that are there. — Michael

That's not a principle of realism.

Realists assume that the world exists independently of our beliefs and statements. You should not conflate that with talk about experiences and seeing, because many realists differ on questions on the nature of experiences and seeing (direct vs indirect realism).

Material chairs are made up of physical stuff such as atoms and their bonds. Mathematical chairs only have mathematical properties. There is no physical stuff. Surely you've heard of Max Tegmark and his claim that the universe is mathematical. Instead of particles or fields or space being the ontological structure, it's numbers and their relations. — Marchesk

Ok so if I see a chair, how do I go about deciding whether it's made up of atoms or mathematical properties? What are the real differences between chairs made of mathematical properties and those made of atoms? Do they look different, smell different, behave differently? What's the difference between them?

Don't you see that these are all differences without a difference? What I call a mathematical property, say ratio, is something observable in experience right? What I call an atom is also something observable in experience. Hence all these things are defined RELATIVE to experience. What I call matter i know from my experience. A stone is matter because it's hard, I grab it in my hand. It has mass, i can weigh it. That's all that being matter means. That's what i am actually communicating when I say something is matter. There is no more mysterious matter beyond experience. All I know is all I can potentially experience.

Yes — The Great Whatever

Good, if you're sure that you can do it, then I assume that you've already done it. So, how did you imagine it then? Did you picture someone going out and cutting some christmas trees, or did you think about what it means to cut a tree, and then multiply that by seventy? Or did you use some combination of imaging and thinking about the meaning of the words? Did any images enter your mind when you thought about what it means to cut a tree? I'm interested to know what process you use to imagine something without picturing it?

What I call an atom is also something observable in experience. — Agustino

Not until electron tunneling microscopes were invented. Atoms were purely theoretical constructs created to explain the various forms matter takes (or to be more accurate, ontological posits), and then later, various experimental results. Now that we have tools to see and manipulate atoms, they're more than just theoretical abstractions. Also, chemistry doesn't work at all without atoms.

All that being said, atoms aren't fundamental, they're made up of subatomic particles and you have all the QM probability wave weirdness going on. Also, the particles themselves are said to be point particles, meaning they have no length or width. But more importantly, atoms, photons, electors, are abstracted away from colors, tastes, etc of everyday objects. What we know of them is physics, which is heavily based on math. Which leads to the possibility that the only real properties are mathematical properties.

Consider the table. It feels solid, looks brown and polished, sounds a certain way when you thump on it. But all of that can be explained in terms of light and sound waves, empty space with tiny atoms bound together by some magnetic force. The table of physics is very different from the table we see or hear or feel.

Which leads to the possibility that the only real properties are mathematical properties. — Marchesk

And where does maths exist?

SX and Aaron R have given the answer to the question you were asking. I would add that all of the responses you list are, in some sense, true.

1. is correct. The parts of the world we perceive are as we perceive them.

2. is correct. Our observations and measurements of the world represent the world as it acts (this is really 1. repeated in the context of the practice of science).

3. is correct. Existing states express mathematical forms all the time.

4. is correct. Anything we know is, by definition, related to anything else (identity, difference) and cannot be known any other way.

5. is correct, in a sense. When one knows something, it is a representation in in a state of their experience, not the the thing they know about itself. In this sense, everything is unknowable, not because it cannot be known, but rather because it never knowledge-- a state known is never the state of knowledge.

6. is also correct. This is 4. stated in a different way. Since we are a difference, everything is in relation to us, so nothing can be said to be "independent" of us.

Did you picture someone going out and cutting some christmas trees, or did you think about what it means to cut a tree, and then multiply that by seventy? — Metaphysician Undercover

No, which makes me think these notions of imagination have to be wrong.

No, which makes me think these notions of imagination have to be wrong. — The Great Whatever

I'm just speaking from my experience, that's how I imagine such a thing. I picture in my mind, a person with a saw, going and cutting a tree. Then I tell myself seventy times. And to imagine this, seventy times, I try to picture 70 in relation to other numbers like 60 and 50, but this seems somewhat vague. So I picture seven in relation to one by counting in my mind, and tell myself ten times that. Then I picture ten as two groups of five. Now I can imagine ten groups of seven, and this is the number of times that the person cuts trees. In this way I can avoid picturing the person cutting a tree seventy times.

I strongly believe that we all think differently though, thinking is an idiosyncratic matter. That's why I'm asking you, how would you imagine such a thing?

Then I tell myself seventy times — Metaphysician Undercover

Really? That seems exhausting and pointless, and not the way people imagine things.

I think naive realism is not a coherent metaphysical position if one supplements it with the claim that one has some reason to believe it. If one wants to assert it dogmatically, then it's I suppose possible in principle, but by its own logic I think it rules out the possibility of having any evidence for it. — The Great Whatever

Maybe you could explain this a bit more (if you haven't already . . . I haven't read all of the posts below this one yet).

What is the world independent of us? — Marchesk

No idea!

Naive realism strikes me as incoherent, on any sort of reflection. But our perceptions have this sort of 'naive realist' quality to them. It really feels like my eyes shoot out a gaze at objects which exist in an independent world (i.e. not dependent on my mind). As if I look through my eyes. It feels like the laptop I'm touching is 'out there' and 'not me'. But when we learn about the biology of our sense organs, they don't seem to support this. Looking at the eye for example, the retina just responds to light by shooting off charges into the brain. There's nothing in the biology of the eye which would support a gaze through it.

Realism has no explanatory value. It shifts the 'unexplained' level of reality out from the ideal into a mind-independent world. The realist has no problem with unexplained things, he just has a problem with perception/ideas being that unexplained (as in, it doesn't have something else which is causing it) thing. For some reason the realist is more comfortable with the unexplained 'level' of reality being the material world instead of the ideal. Even though they have to posit an entire 'level' of reality, for no real explanatory reason. I actually think the reason the realist is more comfortable with the material world being the uncaused/unexplained level of reality is due to the school system. In our classes on biology, or physics, or chemistry, we're taught atomic realism, physicalism, biological materialism. Basically we are taught that materialism is the case until we're 18 years old, and beyond into higher education. The realist just struggles to shed this indoctrination.

I wonder why there's no 'super-realism' position? As in, our perceptions are caused by a material world, which isitself caused by some other level of reality. The realist would probably see this position as silly. And yet he does the very same thing in relation to the ideal 'world'. He sees the ideal 'level' of reality as needing an explanation and a cause, and yet has no problem with the material level of reality not needing a cause nor explanation. His problem is not with things which cause their own existence (as in, nothing causes their existence or 'holds' them in existence), in principle. He just has a problem with ideal things causing their own existence. And like I say, I think this double standard comes down mostly to the education system; 18 years of being indoctrinated into realism.

But I also think that idealism assumes too much. Nobody knows there isn't a material world. And there's something intuitively repugnant about the idea that this laptop before me is merely constituted by my perception of it. Intellectually I can peel away my visual perception, the touch of my fingers, etc, ask myself "what's left?" and struggle for an answer. But it just seems wrong that there would actually be nothing! It's a sort of paradox, realism seems intuitively obvious, our perceptions even have a naive realist quality. And yet on reflection, intellectually the position appears incoherent. Or at the very least pointless.

Basically any actual position taken towards this question goes too far, in my opinion. We just don't know. And it's all made way more complicated by inter-subjectivity - how is it that other minds fit into the picture. Idealism struggles with solipsistic tendencies, and yet realism places other minds in a noumenal (as in, entirely independent/separate from our own minds) realm, which is solipsistic in its own right. We (at least me) want direct encounters with others, and yet have what's encountered be, in-principle, incomplete/not all there is to others. A direct encounter with something which transcends ourselves.

Not until electron tunneling microscopes were invented. Atoms were purely theoretical constructs created to explain the various forms matter takes (or to be more accurate, ontological posits), and then later, various experimental results. Now that we have tools to see and manipulate atoms, they're more than just theoretical abstractions. Also, chemistry doesn't work at all without atoms. — Marchesk

No they aren't purely theoretical constructs. They are constructs that suggest such and such behaviour in such and such situations. That's what we meant by atoms - things which behave so and so in such and such. Then we do the experiment, and we notice such and such behaviour. Therefore we conclude that our conception must be correct - because our conception simply is that behaviour in that circumstance. And we don't need electron tunneling microscopes to experience atoms. Experience of atoms is experience of anything that behaves like atoms.

All that being said, atoms aren't fundamental, they're made up of subatomic particles and you have all the QM probability wave weirdness going on. Also, the particles themselves are said to be point particles, meaning they have no length or width. But more importantly, atoms, photons, electors, are abstracted away from colors, tastes, etc of everyday objects. What we know of them is physics, which is heavily based on math. Which leads to the possibility that the only real properties are mathematical properties. — Marchesk

And if they had a length, would they behave any differently than if they were point particles? The reason why we treat them as point particles is that in order to determine the size of the particles which form a certain other particle, we need to bombard it with something smaller than itself. So we bombard a gold atom with an alpha particle, and we find the size of the nucleus, as Rutherford did. Then we bombard the nucleus by electrons, and other smaller particles, and we find quarks. I don't see any of this being mysterious or pointing to something beyond experience (and by the way, we treat quarks as point particles, because we haven't found smaller particles to bombard them with and see what length they actually have). All that we're talking about is such and such behaving so and so, in this or that circumstance - and we call that an atom. That's what the atom is, everything else is empty abstraction.

Consider the table. It feels solid, looks brown and polished, sounds a certain way when you thump on it. But all of that can be explained in terms of light and sound waves, empty space with tiny atoms bound together by some magnetic force. The table of physics is very different from the table we see or hear or feel. — Marchesk

This guy does it better than you. So what? All that we mean is that the "ordinary" table behaves so and so, because we play with it in "ordinary" circumstances. The "scientific" table behaves so and so because we play with it in different circumstances. In truth they are one and the same table, and all we mean by ordinary and scientific is the different circumstances we play with it.

Really? That seems exhausting and pointless, and not the way people imagine things. — The Great Whatever

Well, it's the way that I imagine things. I can't help it if it's not the way other people imagine things. Now you tell me, how do you imagine this?

I wouldn't say that it's pointless, because it's how I come to a real understanding of what has been said to me, by imagining it. I agree, it does take effort, but that's a simple fact of life, understanding requires effort.

I know that in many of my everyday conversations I simply assume that I understand what has been said to me, without taking the time or effort to imagine it, and I respond accordingly. But those cases I am not imagining what has been said, and sometimes I'm wrong in the assumption that I understand; the result is misunderstanding. So whenever someone says something to me, and I don't feel certain of what they mean, I have to take the time to imagine it. This often requires questioning of the other person, and it may be annoying to that person, but I think it's better to annoy the person in this way, than to misunderstand the person.

So I get the feeling that this is the case right now. I think that I don't really understand what you mean by "imagine", so I'm asking you to clarify this, in order that I can imagine what you mean by "imagine". Since you refuse to answer, I get the impression that I am just being annoying.

This guy does it better than you. So what? All that we mean is that the "ordinary" table behaves so and so, because we play with it in "ordinary" circumstances. The "scientific" table behaves so and so because we play with it in different circumstances. In truth they are one and the same table, and all we mean by ordinary and scientific is the different circumstances we play with it. — Agustino

But this is exactly where the falsity lies. They are not one and the same table. Playing with it in this way makes it different from the other table which we play with in that way. The moment a table is "touched" by someone it becomes different from the table it was, as untouched. The idea that human beings can play with things without changing them is clearly false. And this points to the falsity of the premise of human beings as passive observers.

But this is exactly where the falsity lies. They are not one and the same table. Playing with it in this way makes it different from the other table which we play with in that way. The moment a table is "touched" by someone it becomes different from the table it was, as untouched. The idea that human beings can play with things without changing them is clearly false. And this points to the falsity of the premise of human beings as passive observers. — Metaphysician Undercover

Ok, I agree, but why is my statement contradictory with the statement that human's participate in experience and thus alter it by experiencing it?

What are you asking, if human beings participate in their own experience, and alter it by doing such? That doesn't make sense, because they create their experience.

That doesn't make sense, because they create their experience. — Metaphysician Undercover

No you don't create your experience. You don't have that much power. Part of your experience comes upon you whether you want it to or not. But you participate in the creation of your experience.

I don't see how my experience could be something other than something I create. I'm an active, living being, my experience is a property of myself. Where else could it come from but myself?

I don't see how my experience could be something other than something I create. I'm an active, living being, my experience is a property of myself. Where else could it come from but myself? — Metaphysician Undercover

From the outside world? The fact you go out to work for example, and you meet a lion on the road to work. Is that your creation too? Meeting the lion? Of course not. That's something that you didn't cause, and yet it is part of your experience.

The outside world? Sorry, the outside world is not part of my experience. Please exclude things which are not part of my experience when speaking about my experience. That only causes confusion.

Outside world simply refers to that part of your experience you don't control. You don't control that you'll meet the lion on your way to work. That part of your experience is outside of your control

These things affect my experience, they don't create it, or cause it. That I interpret my surroundings as a lion approaching me, is something created from within me. If my mind is not working properly, I might not even see it as a lion, and be eaten by it, while experiencing something completely different from being eaten by a lion.

Outside world simply refers to that part of your experience you don't control. You don't control that you'll meet the lion on your way to work. That part of your experience is outside of your control — Agustino

Why does the "outside world" have a history? Why are there fossils?

For example, by verification. — jkop

I didn't mean "distinguish" in the sense of "ascertain". I meant it in the sense of the factual difference between a veridical and a non-veridical experience. My understanding is that, according to the realist, there's a way the world is, independent of our experiences, and if our experiences "match" this way then they're veridical, otherwise they're non-veridical.

Realists assume that the world exists independently of our beliefs and statements.

And "the world" here refers to what? Presumably the things we see and talk about (among other things)?

Unless you want to say that the world is separate to the the things we see and talk about, in which case you're confirming Kant's distinction.

You can't imagine a guy chopping down seventy trees unless you literally picture a tree chopping event seventy times over in your head?

You can't imagine a guy chopping down seventy trees unless you literally picture a tree chopping event seventy times over in your head? — The Great Whatever

You didn't read what I wrote? First I imagine what a tree chopping event is. Then, I can imagine 70 by putting it into context with numbers like 60 and 80, but this is a bit vague and doesn't give me a good understanding of how many trees seventy is. I can imagine it better by imagining how many things seven is, and taking that group of seven, ten times. I find it is a bit difficult to imagine how many times ten is, without actually counting out ten, so I find it easier to imagine ten as two groups of five. Then I can imagine chopping seven trees, five times, twice. That's a lot of tree chopping.

I've described how I imagine a guy chopping down seventy trees, you seem to have a hard time believing that this is how I actually do that. Why would you think that I am lying, unless you imagine this described act in another way? So I'll ask again. How do you imagine a guy chopping down seventy trees?

Here's an interesting article written by someone with aphantasia.

Some interesting parts:

7. What is going through your mind all day, if not sights and sounds?

All narration, all the time. An infinite script of milk voice dialogue.

...

9. How do you imagine things?
First I think of a noun in my milk voice: cupcake. Then I think of a verb: cough. Finally an adjective: hairy. What if there was a hairy monster that coughs out cupcakes? Now I wonder how he feels about that. Does he wish he was scarier? Is he regulated by the FDA? Does he get to subtract Weight Watchers points whenever he coughs? Are his sneezes savory or sweet? Is the flu delicious?
If I don’t like the combination of words I’ve picked, I keep Mad Libbing until the concept piques my interest.

Imaginination without picturing seems to amount to just recalling sentences.

These things affect my experience, they don't create it, or cause it. That I interpret my surroundings as a lion approaching me, is something created from within me. — Metaphysician Undercover

If they are created from within you, then it follows precisely that your experience bears no relationship at all with reality, which is nonsense. Your experience necessarily is intertwined with the rest of reality. You cannot be eaten by a lion while experiencing something completely different, that is just ignoring everything we know about how the human organism works.

Why does the "outside world" have a history? Why are there fossils? — tom

That's like asking why we experience the world in time. I'd answer because it's a necessary precondition of any experience at all.