Does it imply that our perceptions are not direct? Could there be other factors involved in perception apart from the the object of perception, sensory organs, memories and experiences?

Exactly. More evidence that the brain (not the eyes) is where objects, real or imaginary, are "seen".

Images in dreams are interesting in the sense that, the dreamer sees images that don't exist in the external world. Where do the dream images come from? You say, well from your memories, experience, and amalgamation of what you have seen before. But there are also images that you have never seen, experienced or the places that you have never been in your life previously in your life.
Where then those images come from?

Of course all the mental images you see and dream exist in your brain. Then while sleep, your brain is supposed to shut down too.

What does it mean for our perception to not exist in a material level? Our perceptions and dreams can have a causal impact on the world, no different than when a errant baseball smashes a window. — Harry Hindu

Let say, you are seeing a wall in front of you. You see the rows of bricks piled to make up the wall. But you also notice, the wall is level with the fence next to it. The walls and fence exist in the external wall in material level (materially, you can go and touch and inspect the walls and fences). But the levelness you perceive don't exist in the world. It exists in your mind or the perceiver's mind.

Likewise, absence of sound, emptiness of space don't exist in material level, but they are perceived by the perceiver in the mind.

Now, the levelness of the walls, absence of sounds (silence), emptiness of space don't exist. Are they then pure product of mind, which are caused by the external objects? Or are they something that exist in the world without being noticed until the perceiver notices them? Because everything we perceive must come from external world.

Images in dreams are interesting in the sense that, the dreamer sees images that don't exist in the external world. Where do the dream images come from? You say, well from your memories, experience, and amalgamation of what you have seen before. But there are also images that you have never seen, experienced or the places that you have never been in your life previously in your life.
Where then those images come from?

Of course all the mental images you see and dream exist in your brain. Then while sleep, your brain is supposed to shut down too. — Corvus

If it did shut down completely you wouldn't be able to wake up to loud (and possibly dangerous) noises in the world.

The places in your dream are amalgams of places you have been in the world. By using an amalgam of places you have been you can create unique places.

There is also the issue of how sensory deprivation can cause hallucinations. When you are asleep, you are being deprived of sensory input, but not completely or else you would not be able to wake in when in danger. The lack of visual input can cause you to hallucinate, or dream in the case of being asleep. You can hallucinate places you have never been, but they all are amalgams of places you have been. Even if you never experienced the idea of extra-terrestrial aliens, you might still arrive at the idea via incorporating several different ideas about life and its existence on other planets.

Let say, you are seeing a wall in front of you. You see the rows of bricks piled to make up the wall. But you also notice, the wall is level with the fence next to it. The walls and fence exist in the external wall in material level (materially, you can go and touch and inspect the walls and fences). But the levelness you perceive don't exist in the world. It exists in your mind or the perceiver's mind. — Corvus

But this goes back to what I said about thinking that humans are separate from the world. We are not. If the ideas in our mind can cause things to happen in the world then it seems to me that the mind is on the same level as the world. You are simply trying to make a special case for minds, but all that does is cause problems in trying to explain how the mind and world can interact causally when we know that they can - from experience.

Likewise, absence of sound, emptiness of space don't exist in material level, but they are perceived by the perceiver in the mind.

Now, the levelness of the walls, absence of sounds (silence), emptiness of space don't exist. Are they then pure product of mind, which are caused by the external objects? Or are they something that exist in the world without being noticed until the perceiver notices them? Because everything we perceive must come from external world. — Corvus

Ideas exist. They have a causal impact on our behavior in the world. The idea of Santa Claus causes some people to behave in certain ways in the world. To say that Santa Claus exists in the world instead of in your mind is to simply make a category mistake, not that Santa Claus doesn't exist. It does exist - as an idea, and it exists on the same level as the world because the idea can cause things to happen in the world. That is not to say that the world is made of ideas. Ideas are a complex arrangement of information and it is information that is fundamental, not ideas.

If it did shut down completely you wouldn't be able to wake up to loud (and possibly dangerous) noises in the world. — Harry Hindu

Seeing something means there was an object in the physical world, which came into your retina in the form of lights, and activated your neurons and converted into images, which was transferred into your brain. But in the case of seeing an object in your dreams, you have no external object, which causes all the seeing process.

So what are you actually seeing, when you are seeing a tiger trying to attack you in your dream?

Seeing something means there was an object in the physical world, which came into your retina in the form of lights, and activated your neurons and converted into images, which was transferred into your brain. But in the case of seeing an object in your dreams, you have no external object, which causes all the seeing process.

So what are you actually seeing, when you are seeing a tiger trying to attack you in your dream? — Corvus

The same type of thing you experience when you make predictions, goals, solve problems, etc. Imagining is part of the process that we use to make predictions and solve problems. One might argue that the more imaginative you are, the more intelligent you are, as you are able to come up with novel ideas to solve problems. When we are awake, most us are able to distinguish between what the world is informing us via our senses and what we imagine. Some with mental disorders like schizophrenia are unable to make this distinction.

When you are asleep you do not have the external world to compare, so you are similar to a schizophrenic when you are dreaming. Dreaming is simply the same process as day-dreaming, or making predictions when you are awake, but without external stimuli to ground you.

Can different images be amalgamated into totally different another image?
- That's basically what amalgamate means. Combining image 1 with image 2 results in an image that is neither image 1 or 2. So, the answer is obviously, yes.

Who do you get if you amalgamate images of Elon Musk with Bill Gates, Taylor Swift and Madonna?
- Someone who isn't Elon Musk with Bill Gates, Taylor Swift or Madonna

Why would you do that?
- To come up with a new image.

The same type of thing you experience when you make predictions, goals, solve problems, etc. Imagining is part of the process that we use to make predictions and solve problems. — Harry Hindu

Seeing a tiger attacking you in your dream is "seeing something" i.e. seeing an image and motion. It doesn't seem to have anything to do with making predictions, solving problems etc.

That's basically what amalgamate means. Combining image 1 with image 2 results in an image that is neither image 1 or 2. So, the answer is obviously, yes. — night912

Combining image 1 and 2? doesn't make sense to me. How do you combine images? Combine something means mixing something. To mix something you must add 1 substance to the other substance, which is only possible with liquid or powder stuff. If you put down image 1 to image 2, then image 2 will be invisible blocked by the image1. What is going on here?

Someone who isn't Elon Musk with Bill Gates, Taylor Swift or Madonna — night912

You were talking about the images, but suddenly now you are talking a person called someone?

To come up with a new image. — night912

I don't. Do you? Why do you want to come up with a new image?

Combining image 1 and 2? doesn't make sense to me. How do you combine images? Combine something means mixing something. To mix something you must add 1 substance to the other substance, which is only possible with liquid or powder stuff.

You just proved that you're wrong. You combined letters above, resulting in sentences. :up:

If you put down image 1 to image 2, then image 2 will be invisible blocked by the image1. What is going on here?

How does image 1 and 2 make image 2 invisible ? What is going on here? :chin:

You were talking about the images, but suddenly now you are talking a person called someone?

You were talking about images of people, but suddenly now you are talking about a person called someone? :chin:

I don't. Do you? Why do you want to come up with a new image?

I do. Why don't you want to come up with a new image? :chin:

Seeing a tiger attacking you in your dream is "seeing something" i.e. seeing an image and motion. It doesn't seem to have anything to do with making predictions, solving problems etc. — Corvus

That is why I explained in the same post that you cherry-picked that predictions are a type of imagining, and dreams are a type of imagining where you do not have the external world to ground your experience.

What it is like for you to make a prediction and to imagine things when you are awake?

You just proved that you're wrong. You combined letters above, resulting in sentences. :up: — night912

I didn't combine anything at all. I just chose words to make up sentences. Anyway, it is not the same thing as seeing the images in your dreams.

What it is like for you to make a prediction and to imagine things when you are awake? — Harry Hindu

Seeing images in your dreams and making predictions are totally different things happening in your mind. They are not the same activities. Seeing something is visual. Predicting something is imagining. There are two types of prediction. One by your hunch, and the other by inductive reasoning. Both activities involve your intention, will and inference.

Seeing visual images in your dreams is random events happening without any of above. Plus it is visual operation with no imagination, guessing or reasoning.

Seeing images in your dreams and making predictions are totally different things happening in your mind. They are not the same activities. Seeing something is visual. Predicting something is imagining. There are two types of prediction. One by your hunch, and the other by inductive reasoning. Both activities involve your intention, will and inference.

Seeing visual images in your dreams is random events happening without any of above. Plus it is visual operation with no imagination, guessing or reasoning. — Corvus

Imagine imagining something when you don't have the world imposing itself on your senses and mind. The imagining would seem real, like your dream does. The dream would take the place of the world precisely because the world is absent when you are asleep.

You're not seeing anything when you dream. Seeing is the process of using your eyes to take in light. The existence of light is a necessary component of seeing. Can you see anything when the lights are out? You are simply misusing terms.

Imagine imagining something when you don't have the world imposing itself on your senses and mind. The imagining would seem real, like your dream does. The dream would take the place of the world precisely because the world is absent when you are asleep. — Harry Hindu

I saw a tiger in my dream. I do vividly remember the image of the tiger, so that I can even draw it on a piece of paper how it looked. It is a visual experience, which is similar to the visual perception you have in your daily life.

It has nothing to do with making predictions or imagining something for the reasons I have put down on my previous post. Please read it again, if you haven't.

You're not seeing anything when you dream. Seeing is the process of using your eyes to take in light. The existence of light is a necessary component of seeing. Can you see anything when the lights are out? You are simply misusing terms. — Harry Hindu

Hegel and Kant have written about the images we see in our dreams as "inner impressions" which are different type of impressions coming from the external world.

I have not used any vague terms or fancy words in my posts, but just said seeing images in dreams are different type of images we see when we are awake in daily life.

You seem to be misusing the word "misuse" without knowing what the word "misuse" actually means.

So where do the images come from? Does this phenomena implies that human perceptions could occur without actual existence of objects? Do human perceive things all differently?
Can humans perceive objects which don't exist? — Corvus

Human consciousness, by the latest research, revolves around our brain being a prediction machine; "predictive coding theory".

Our perception of reality is basically a controlled hallucination, with our sensory inputs grounding our hallucination so that we can navigate reality. Without that grounding, we hallucinate by the textbook sense of the word. Psychedelic drugs activate such unbound hallucinations by obscuring the flow of sensory information and increasing the brain's predictive measures and in so dislocates us from reality.

This also happens when we dream. The brain predicts without grounding, and because of it we are essentially forming a feedback loop in which we predict based on nothing but memory, that is then fed into itself as the grounding information and because of this unbounded nature, it "swells" into the abstract and surreal nature of our experience.

Like...

So it seems that our minds are not completely shut off from the world and we interpret external stimuli as part of the dream. — Harry Hindu

Is supporting this theory. Real world sensory information starts to ground the dream as we return back to normal processing.

We are, as Harry says, not dislocated from existence when we dream. We are connected through our memories as the source for our dreams, but unbound to reality in a loss of sensory grounding. Previous research theorized that dreams "manage our memories" and help us categorize and organize our functions. Since if we deprave people of sleep, they become disoriented with reality. With the recent research, it also points to our predictive ability becoming skewed and broken, since we hallucinate when depraved of sleep. Dreams may therefor be our way of "consolidating memory and categorization" while calibrating our predictive function and stream of memory information.

In essence, while sleep resets and balance chemicals in our body, it further cuts off sensory grounding in order to calibrate this link and process. The sensor data that is stored as raw data of short term memory is a very energy costly process that is a strain on our brain, like a muscle. And just like we need to let our muscles heal when pushed to the limits, we need to let the brain organize our short term memory into long term experience for the sake of purging the short term memory so that the next day we can use the previous day experience as coded data used with our prediction function and in turn store new short term memory in order to further reshape the long term coding.

It further supports why children are better at learning and have changing sleep patterns while they grow up; and why the older we get, the more stable our navigation of reality become. Less erratic, and more wise. As long as learning and experiences keep continue in our adult life.

It also supports why the continued use of our brain in old age, help keeping dementia and declining cognitive function away, since just like training our muscles in old age becomes harder, if we don't do it, we quickly deteriorate.

And it supports research into learning, how tests are clear that when we do something intensely before sleep, then the next day we have become slightly better at it.

And this is why sleep and dreaming is so important. Especially if you are feeding a lot of new experiences and information to the brain. The more you learn, experience and do things differently during a day, the more the brain needs to go through enough sleep to settle that information into predictive coding.

We use this to automate our functions and behavior. The more we do something, the more we automate it as the prediction becomes better. The reason we don't think about how we ride bikes is because the predictions are automated, we don't need to.

Getting better at something, therefor is a process of automation. Which can also have the negative effect of automating bad information into the process.

Which is a good explanation for our cognitive biases becoming more rigid the more we focus on just information that aligns with what we already know. And why broadening our knowledge is key to becoming truly wise.

Which is a good explanation for our cognitive biases becoming more rigid the more we focus on just information that aligns with what we already know. And why broadening our knowledge is key to becoming truly wise. — Christoffer

A detailed and good post on the topic. Thank you. However, the OP was more interested in discussing and find out the nature of the visual images we see in our dreams, rather than how dreams work, and why we dream.

Clearly what we see in our dreams are images of the objects in the external world. But some of the images are the ones that we never came across in daily lives, or have anything to do with our experience and memories. The white tiger I have seen my dream for example, was a clear vivid image of a tiger, but I have never seen it in my entire life in real world.

So where does it come from? How is it different from the images we see in daily life from the real objects? Are they same type of images? Then how it does not have its real existence of the object?

It was more the epistemological angle the OP was trying to orient the discussions.

However, the OP was more interested in discussing and find out the nature of the visual images we see in our dreams, rather than how dreams work, and why we dream. — Corvus

It's in there in the post. All hallucinations in our dreams are the result of ungrounded hallucinations based on the past memories in our short term and long term memory.

But some of the images are the ones that we never came across in daily lives, or have anything to do with our experience and memories. The white tiger I have seen my dream for example, was a clear vivid image of a tiger, but I have never seen it in my entire life in real world. — Corvus

This make little sense as hallucinations are failures of prediction. If your brain tries to predict a tiger and you know that white tigers exist, the ungrounded prediction function may produce such a hallucination. It's at the core of what happens when predictions aren't verified by a flow of sensory data.

It also makes little sense by just mentioning art. Artists do this all the time. Imagination is a form of controlled manipulation of our predictions. Are you saying that you cannot possible imagine a pink elephant, even though you have never seen one?

It's just a merge of previously known concepts that you mash up internally. You know pink and you know elephants and now you can expand that hallucinatory imagination to highly detailed rendition of the pink skin on that elephant.

The difference is that dreaming and psychedelic drugs enable a much more intense experience of it since it since it dislocates you from the constant flow of sensory flow data as well as the lack of ability to take action in sync with our prediction function makes the flow of that experience very abstract and nonsensical.

It's why if people close their eyes they seem to have a better ability to imagine something. They essentially subdue the visual sensory flow of data and frees up that grounding mechanism, making it easier to imagine something.

So where does it come from? How is it different from the images we see in daily life from the real objects? Are they same type of images? Then how it does not have its real existence of the object? — Corvus

When you look at a cup of coffee, your eyes and your sense of smell constantly feeds your brain with sensory data. Your brain is processing this in relation to memory of cups, coffee, the table which it stands and so on. It uses the sensory data to verify that our internal prediction is correct so as to move our experience forward in time. If we cut of that verification data, nothing prevents our predictions to run out of control, reshaping the color of that cup as we've seen other cups with other colors, or imagine new forms of a cup since nothing grounds our categorization of what "a cup" means to us.

So the question of "where does it come from" and how it differs from real objects becomes somewhat of a nonsense question. Your experience of real life is an hallucination that is verified by the real object. That process forms memory categories that becomes the foundation of how we think about reality and the world around us.

But it's still just an hallucination stored in memory and hallucinations can take any form if nothing grounds it.

And artists create things out of their imagination all the time and these are all coming from their internal manipulation of memorized concepts. Tapping into a similar form of ungrounded hallucination.

I'm not sure where you're going with the OP question, what you are aiming for, but there's not much more to it than what I described. Our experience is an hallucination bound by a flow of sensory data. Cutting that flow makes us hallucinate freely and our memorized concepts start to merge into new forms, shapes and concepts. The combinations of concepts stored in our memory has an almost infinite amount of combinations. A white tiger included.

I think the consistency of normal experience and our ability to compare to perceptive fabrications (e.g., hallucinations, dreams, etc.) are evidence that something normally is exciting your senses; but what that thing is in-itself is impossible to know. It very well could be a mere idea (like ontological idealists say) or a concrete object (like materialists will say) or an object (like physicalists will say) or something unimaginable.

I'm not sure where you're going with the OP question, what you are aiming for, but there's not much more to it than what I described. Our experience is an hallucination bound by a flow of sensory data. Cutting that flow makes us hallucinate freely and our memorized concepts start to merge into new forms, shapes and concepts. The combinations of concepts stored in our memory has an almost infinite amount of combinations. A white tiger included. — Christoffer

Yet again, isn't Hallucination totally different way of seeing non existent objects? You see images of the objects which are existent or non-existent in the external world, but the cause of the seeing is the abnormal state of your brain due to the chemically induced condition? I am not too sure on the details of technicality of hallucination on why and how it occurs. But that is my idea on it. Anyway, it is not the OPs interest here.

Asking and discussing on seeing non-existence images in dreams and also daily life could tell us more on our perception how it works, which could allow us to explore on the way mind works.

If you think it has no more scope of discussion than talking about hallucination and making predictions, then maybe you are not interested in the topic of the workings of mind and perception.

I think the consistency of normal experience and our ability to compare to perceptive fabrications (e.g., hallucinations, dreams, etc.) are evidence that something normally is exciting your senses; but what that thing is in-itself is impossible to know. It very well could be a mere idea (like ontological idealists say) or a concrete object (like materialists will say) or an object (like physicalists will say) or something unimaginable. — Bob Ross

Yes, this is it. The thing in-itself which is impossible to know or something unimaginable is what we hope to find out.

I saw a tiger in my dream. I do vividly remember the image of the tiger, so that I can even draw it on a piece of paper how it looked. It is a visual experience, which is similar to the visual perception you have in your daily life.

It has nothing to do with making predictions or imagining something for the reasons I have put down on my previous post. Please read it again, if you haven't. — Corvus

You did not see a tiger. You dreamed a tiger. This is how you are misusing terms.

A prediction is an imagined future. You may predict you will see a tiger when you go to the zoo. The tiger you predicted is similar to, but not exactly like the tiger you now see when at the zoo and you can draw a picture of the tiger you imagined and the one you saw at the zoo so I don't see how your explanation shows that dreamed tigers are not like day-dreamed or predicted tigers when awake. Because you are awake, you have no problem distinguishing between imagining and the tiger at the zoo. When you are asleep you don't have the world imposing itself on your senses to be able to make that distinction.

Why do you think it is easier to visualize an imagining by closing your eyes as opposed to having them open? Because you don't have the world imposing itself on your eyes. You end up shutting off some of the input that allows you to focus on the details of the imagining.

Hegel and Kant have written about the images we see in our dreams as "inner impressions" which are different type of impressions coming from the external world.

I have not used any vague terms or fancy words in my posts, but just said seeing images in dreams are different type of images we see when we are awake in daily life.

You seem to be misusing the word "misuse" without knowing what the word "misuse" actually means. — Corvus

If Hegel and Kant used the term, "see" when talking about dreams they are misusing terms too. You seem to be making a plea to authority here, when it is just as likely that Hegel and Kant could be wrong, especially when they did not have access to the scientific knowledge we have now.

Yet again, isn't Hallucination totally different way of seeing non existent objects? You see images of the objects which are existent or non-existent in the external world, but the cause of the seeing is the abnormal state of your brain due to the chemically induced condition? — Corvus

The hallucination is the only state. Your perception that is the experience through your senses aren't a 1 to 1 process. You aren't registering photons with your eyes and that is producing an image internally. The experience of seeing is your brain constructing a predicted image that is hallucinated into existence based on the interplay between the sensory information grounding the expectations rooted in memory information.

In essence, when you see a cup of coffee, it forms a constant stream of information that holds in place and time that shape and form while your memory has categorized what a cup of coffee from past experiences and the interplay between them forms a hallucinatory state of predictions about the next step in time we experience.

This way, we see a cup of coffee not as an unknown stream of information, but an unknown stream of information that is evaluated against memory categories of similar objects and producing a constant prediction process of what to expect of this experience.

Without the sensory information grounding experience, this interplay is cut off and our prediction hallucinations start to flow without grounding and forming the abstract and surreal experience that is our dreams or psychedelic trips.

Asking and discussing on seeing non-existence images in dreams and also daily life could tell us more on our perception how it works, which could allow us to explore on the way mind works. — Corvus

But you are also saying:

I am not too sure on the details of technicality of hallucination on why and how it occurs. But that is my idea on it. Anyway, it is not the OPs interest here. — Corvus

You can't ignore the actual scientific research about perception and consciousness which points directly towards explanations on how dreams work, and then say that we can understand how the mind works by discussing in the way you want.

You're asking a question about how we perceive abstractions in dreams, but you don't like the answer so you want to steer it in another direction that ignores the science.

If you think it has no more scope of discussion than talking about hallucination and making predictions, then maybe you are not interested in the topic of the workings of mind and perception. — Corvus

It's one and the same process. It just seems like you ignore what's being said here because it doesn't align with what you believe about the subject.

The images in our dreams are simply based on our past experiences, our memory and our mind forming a predictive hallucination without grounding them through sensory data. You aren't seeing anything, you are perceiving a free flowing predictive process using memory as a bucket of raw data.

Not sure what more's needed to be said to explain it? Even if the science of consciousness haven't a final objective answer on all of it, there's no point ignoring existing research and scientific theories that is as close to an explanation that is currently possible. Anything else is just arbitrary unfounded speculation and belief.

Here's some medieval paintings of animals the artist never saw. They dreamt up the visuals based on descriptions. The more "data" we have before we imagine or dream something, the more accurate those prediction hallucinations become. It's evolutionary logical for a predictive function to work this way. The more experience, the better we are at predicting accurately. You can imagine a white tiger looking just like a white tiger if you've seen tigers before. Our mind can easily switch out a color and basic attributes, but if you actually never saw a tiger you would have a major dissonance if this is what you imagined and then saw a real tiger.



Or an elephant:



Or some lions and bears:



Or this poor leopard:




In essence, those were imagined and dreamt up through descriptions of these animals or they got a glimpse in the heat of the moment on some crusade somewhere, and the emotions affected their experience. But they're all trying to form a prediction of what an animal looks like using previous visual experiences and trying to fuse them with other's descriptions. Without any prior visual information, a description will only use what's available in memory.

It's the same process as with AI models forming images. If they don't have enough data on tigers in lots of situations, they will not be able to predict an image into an accurate depiction of what a tiger looks like. The more memory data of tigers, the more accurate it makes them. Our mind works in the same way. It's the reason why we began experimenting with neural nets in computer science in the first place, because it has correlation with how neurons work and how the brain works. It's only now we're starting to form theories of why this is.

In some cases artists have very little to draw from.

Poor guy:




And this is why religion forms so easily. A lack of information and explanations lead to extremely abstract ideas that try to predict why something is happening around the individual. And why the comfort of someone spreading an explanation lessen the strain on the mind to construct accurate predictions.

It may even be the reason why we form social groups. That in order to efficiently speed up the process of prediction in cognition, a group of people spread ideas among the group rather than each individual having to learn on their own.

You did not see a tiger. You dreamed a tiger. This is how you are misusing terms. — Harry Hindu

When I was in sleep, I was seeing a tiger. When I was awake, I recalled the dream of a tiger. They are both images, not words or sounds.

If Hegel and Kant used the term, "see" when talking about dreams they are misusing terms too. You seem to be making a plea to authority here, when it is just as likely that Hegel and Kant could be wrong, especially when they did not have access to the scientific knowledge we have now. — Harry Hindu

I didn't say Hegel's idea was absolute truth. I found Hegel's term "inner impressions" for seeing images in dreams interesting. In Hume impressions come from the external world objects. When the impressions come into your mind, it becomes ideas. There is no such a thing as "inner impressions".

A very interesting and detailed post on the topic. Thank you. I will read it over, and get back to you, when I have some ideas about your points. The images in the posts are very interesting too. Later~

In essence, when you see a cup of coffee, it forms a constant stream of information that holds in place and time that shape and form while your memory has categorized what a cup of coffee from past experiences and the interplay between them forms a hallucinatory state of predictions about the next step in time we experience. — Christoffer

Do you mean that we never see a real cup of coffee, but images of constant steam of information from your memory, which is a hallucinatory state of predictions?

I recall debating on this topic before. The direct realists would say, you are seeing a cup of coffee in front of you, and indirect realist would say, you are seeing a sense data of a cup of coffee which seems sounding similar to your suggestion.

You say it is a scientific facts, but is it tested, and proven fact? Or would it be just another hypotheses how seeing works?

Do you mean that we never see a real cup of coffee, but images of constant steam of information from your memory, which is a hallucinatory state of predictions?

I recall debating on this topic before. The direct realists would say, you are seeing a cup of coffee in front of you, and indirect realist would say, you are seeing a sense data of a cup of coffee which seems sounding similar to your suggestion. — Corvus

Both speak of two sides of the same coin, neither is correct in just their single concept. And the third part is the prediction function which they don't even include.

We need to see the system as a whole of different parts. We do have a real sensory, raw data flowing from our registration of photons and molecules, this is as real as a still camera registering signals ont he CMOS sensor into raw data.

Then we have a visual cortex and parts of the brain directly processing visual sensory data .

However, that is not enough on its own. In order for our brain to make sense of this sensory data it needs to correlate it with something it already knows, so it correlates it with memories of cups of coffee, every map of neurons possible for that concept in order to verify that it is a cup of coffee. The map of neurons firing out of the sensory data is essentially being correlated with the map of neurons firing out of memory.

If it marches up, it transforms into an internal image that is basically an hallucination of all our stored memories of cups of coffee being hold into place by the raw sensory data creating a bias towards the specifics of that real time current stream of sensory data.

In essence, if the cup is blue and it steams in the rays of window sun, this data produces a bias towards similar concepts in our mind forming an interplay between memory and raw sensory data that generates this internal image.

And over time our mind uses this interplay to predict the next moments in time by constantly using our memory of cups of coffee as a foundation for that prediction and rooting a bias of that prediction with the sensory data and possible scenarios of the future for that cup of coffee, forming an illusion of motion ideas of navigation going forward.

This process seems simplistic, but if you expand and include every single object, every single memory, everything that makes up the internally formed memory and possible predictions about everything around us, it starts to form a basic structure of how humans navigate with their consciousness.

On top of that, the very act of this interaction with this blue cup is in itself adding new memory data for future events. Meaning that every single second we are gathering extreme amounts of memory into our short term memory.

This is then sifted through and organized during sleep, with similarities in situations being shaped as stronger biases for better prediction functions in similar situations. Meaning, if you work as a barista and handle cups of coffee all day long for many years, your mind is essentially an expert on anything related to the concept of navigating "cups of coffee" around you as you have formed so much memory about cups that almost any scenario can be predicted by your brain.

It's why we can experience things like "flow", or automatic behaviors like juggling. Because the training has supercharged our predictions about those specific objects around us, giving us the ability to function beyond having to think about them in the moment.

And when we sleep, our mind is essentially cutting off the sensory data and starts to "play around" with predictions based on primarily the new memory data we gathered during the day. A form of testing ground to compare the new data to old data with a free form trial and error of prediction actions onto these memories. Which finds support in how dreams behave; usually forming around recent events, but at the same time lifting out old memories or people from long past because our mind is trying to categorize a new memory to what it things is a close match in the neural mapping between the old and new memory.

You say it is a scientific facts, but is it tested, and proven fact? Or would it be just another hypotheses how seeing works? — Corvus

It's based on the most recent research on how our consciousness works. It's not a single fact, it's consistent of a number of facts with a number of observations and hypotheses. There are a lot of tests done on our cognition, both neurologically, behaviorally and sociologically that form specific areas of proven concepts that are then put into a holistic hypothesis and new research.

When I say it's the latest research in science it's what's the most up to date. And it is the least speculative of all speculations surrounding our consciousness and how our perception, experience and how dreams work.

I'm just drawing up an extremely simple description of all this with predictive coding at the center, but it's a concept that gathers many fields into one holistic form. If you want to check out the underlying idea more here's some more: https://en.wikipedia.org/wiki/Predictive_coding
And there's more to go from there, check the hyperlinks etc. And there are many research papers on the subject if you search for it and then follow citation hyperlinks for further papers.
https://www.nature.com/articles/s41562-022-01516-2
https://link.springer.com/article/10.1007/s10339-016-0765-6
https://arxiv.org/abs/2107.12979
To mention just a few.

But there's a large body of research, empirical tests as well as theoretical concepts out there about this.

And the third part is the prediction function which they don't even include. — Christoffer

Predictions usually happen when the result of some events, movements of objects or processes are unknown to the predictor. But in visual perception of a cup of coffee, result of the perception is irrelevant with the unknown-ness or uncertainty. This tells us prediction is not relevant in most daily visual perceptions. It looks more so, in seeing the objects in dreams.

The OP is also about "non-existing objects" and existing objects. How do we perceive non-existing objects, and what are the nature of non-existing objects? Do non-existing objects exist? If they do, how can they be non-existing? If they don't, how could we see them? Are seeing a reliable evidence for existence of objects? If not, what are the evidence of something to exist?

How are they different from existing objects?

Predictions usually happen when the result of some events, movements of objects or processes are unknown to the predictor. But in visual perception of a cup of coffee, result of the perception is irrelevant with the unknown-ness or uncertainty. This tells us prediction is not relevant in most daily visual perceptions. — Corvus

The example with the coffee cup is an extremely simplified version of what the prediction function is in order to explain the process.

The prediction function is a constant flow, it has nothing to do with the known or unknown state of something. Studies on infants show how the mental models of their surroundings are incomplete, but quickly forms into rudimentary predictive navigation as they grow into young children. Every human start out in this extremely basic state in which our brain is gathering enough neural paths to conduct basic spatial and social navigation through predicting future states in time. But as we grow older, it forms an exponentially growing complexity not only to navigate spatially and behaviorally, but conceptually. We begin to form a sort of rudimentary control over the prediction process in the form of imagination, helping us to test scenarios for navigation through unknown territory. However, this imagination is built on previous knowledge and correlations between previously mental models of scenarios and objects.

The prediction function is not a detached function of our brain like the visual cortex, it is the fundamental function of the entire brain. It fundamentally is our brain.

I recommend that you read more about it because I don't think you grasped the concept fully yet. It's not a part of our cognition... it is our cognition.

The OP is also about "non-existing objects" and existing objects. How do we perceive non-existing objects, and what are the nature of non-existing objects? How are they different from existing objects? — Corvus

I don't see how this isn't answered? How we perceive non-existing objects has already been answered. It's a hallucinatory flow of predictions detached from sensory inputs and composed by a collage of previous experiences and concepts of objects that we have stored in memory. The nature of them is that they are hallucinations detached from sensory information or minorly influenced by it while imagining or hallucinating in an awaken state. Internally they differentiate to existing objects in that they are pure memory information formed into prediction calculations by the brain that detaches from sensory grounding, transforming memory representations of real objects into a malleable conceptualized mental model that can be reshaped internally. During dreaming, this process happens without our ability to control it, since the flow of this collage of memories flowing together is influenced by the brain's process of fusing long term memory with the new short term memories.

You are essentially asking for a summery of the entire field of perception and cognition and I'm trying to make a short simplified description, but you have to engage with the material fully to understand the answers to your questions.

I'm not sure what else you're asking for, because with this field of science in mind, the answers are somewhat clear or at least rationally explained enough by the current understanding of our consciousness and how we function.