Visual reality: a new insight.

[lifegazer]

The materialists amongst you argue that photons enter the eye and that the eye sends info to the brain about these photons. The brain then transforms this data into abstract experience upon awareness, thus representing external reality.

Here's the question: How does the eye and/or brain know what distance any specific photon has traversed through space?
You can argue that a photon has a frequency and wavelength, but neither will tell you the length that photon has travelled. There may even be a large ensemble of such photons, from a single object. Yet what info is inherent within any of them that will inform the eye or brain the distance they have traversed? Given that all photons traverse space at the same speed, the answer appears to be that there is no info.

Let's conduct a thought experiment to get my point across: Imagine that you are blind. Now imagine that everyone around you has a water-pistol and is shooting water at you. Your skin might be able to tell you from what direction the water has come, but if we imagine that all incoming water has the same velocity (thus mirroring the same impact of the photons), then it appears impossible for the skin and/or brain to know what distance that water has traversed.
Hence, it would be impossible for the brain to create a 4-dimensional abstract representation of its external reality.

... Similarly, the same case applies for incoming photons. There is no way an incoming photon can impart the distance it has traversed to the eye/brain.
I suggest that this is evidence to prove that abstract awareness is not dependent upon an external reality.

 

[Andonyx]

What You're correct, there is no direct information imparted by a photon as to what distance it has traveled.

So?

What does that have to do with anything? This impacts our sense of sight in no way whatsoever.

 

[lifegazer]

What You're correct, there is no direct information imparted by a photon as to what distance it has traveled.

So?

What does that have to do with anything? This impacts our sense of sight in no way whatsoever.

It's like I said: There's a host of incoming photons going into the eyes (presumably). None of these photons are telling the eye/brain how far they have come.
So please explain to this forum how the brain constructs a 4-dimensional abstract of reality, with the awareness of the distance traversed by those photons built into that construct.

 

[RussDill]

The materialists amongst you argue that photons enter the eye and that the eye sends info to the brain about these photons. The brain then transforms this data into abstract experience upon awareness, thus representing external reality.

Yes, its true, you wouldn't believe the other levels of depravity we sink to.

Here's the question: How does the eye and/or brain know what distance any specific photon has traversed through space?

answer, it doesn't nor does it care.

You can argue that a photon has a frequency and wavelength, but neither will tell you the length that photon has travelled. There may even be a large ensemble of such photons, from a single object. Yet what info is inherent within any of them that will inform the eye or brain the distance they have traversed? Given that all photons traverse space at the same speed, the answer appears to be that there is no info.

That is right, there is no way to know what distance a photon has traveled. Even if you know its source and destination, it could have collided with a particle (or virtual particle) half way through and re-emmited.

Let's conduct a thought experiment to get my point across: Imagine that you are blind. Now imagine that everyone around you has a water-pistol and is shooting water at you. Your skin might be able to tell you from what direction the water has come, but if we imagine that all incoming water has the same velocity (thus mirroring the same impact of the photons), then it appears impossible for the skin and/or brain to know what distance that water has traversed.

Such is the case.

Hence, it would be impossible for the brain to create a 4-dimensional abstract representation of its external reality.

... Similarly, the same case applies for incoming photons. There is no way an incoming photon can impart the distance it has traversed to the eye/brain.

whoa whoa whoa...back up a bit. You are assuming here that depth perception has *anything* to do with individual photons, which it doesn't. Determining how far away something is is based off a number of visual cues, all of which can be fooled.

First and formost, is stereoscopic vision. Most mammilian preditors have two eyes in the front of their face to facilitate stereoscopic vision. With stereoscopic vision, you can determine how far away something is. Simply aim both eyes at the object, and when the two images line up, you can take the angle the eyes are at, and the distance the eyes are apart, and calculate the distance. You can also calculate the distance of things that don't line up based on how far off they are from lining up. You don't have to pull out the trig book though, as a baby, your brain learned how to do all this stuff on its own.

Next would be related to stereoscopic vision, and that would be how far something moves in relation to other things when we move. This method is better when there are a great number of objects, when the objects are far away, or when you only have one eye.

After that, would be blur. If something is blurry while you are staring at things far away, it is probably up close, and vice versa.

Next would be atmospheric effects. Because our sky isn't excactly clear (more so on some days or another). You can determine by examining hue, tint, etc, how far away something is. This one really fools people when looking at pictures of the moon, because a mountain can be hundreds of miles away, and yet, because there is no atmospheric effect, we assume it is much closer.

Also, there is relative size. If we except something to be a particular size, we can use that size to determine how far away something is based on how small it apears.

Don't forget the simple effect of things being further away being partially obscured by things that are closer.

Also, we may go off other sensory cues, such as sound.

I'm sure I'm missing a few, but this should get you started.

I suggest that this is evidence to prove that abstract awareness is not dependent upon an external reality.

Umm..right, really, as far as attempting to show things that have very simple explainations, are unexplained and require your philosophy, you have gone off the deep end.

 

[RussDill]

It's like I said: There's a host of incoming photons going into the eyes (presumably). None of these photons are telling the eye/brain how far they have come.
So please explain to this forum how the brain constructs a 4-dimensional abstract of reality, with the awareness of the distance traversed by those photons built into that construct.

This is easily disproven because someone can be easily fooled into thinking something is closer or farther away than it really is. If your philosophy were true, such a trick would not be possible.

 

[I'll_buy_that]

troll!

 

[Crossbow]

Just ot echo the fine comments made by RussDill,

True, there is no distance data embedded within the photons;
However, we have two eyes that have a bit of horizontal separation between them and by simultaneously combing the pictures from the left and right along with our high power brains we can judge distances to various objects through the process termed depth perception.

Materialism really does not have anything to do with it.

 

[Andonyx]

This is easily disproven because someone can be easily fooled into thinking something is closer or farther away than it really is. If your philosophy were true, such a trick would not be possible.

And you forgot that his philosophy would dictate that depth-perception as a sense would be identical with one eye or two eyes.

We know of course that someone with one eye has far less reliable and specific depth perception than someone with two.

(They still have some due to parallax and perspective, but it's not nearly as good as binocular vision in unfamiliar circumstances.)

 

[Mercutio]

Lifegazer...a simple question for you. I have on my bookshelf a book which would answer for you every aspect of this current puzzlement. It is a book on Visual Perception (this one happens to be by Sekular & Blake, but there are a dozen or more others which are every bit as current and as thorough), and it covers in detail what "materialists" know about visual perception.

I'm sure you can find an equivalent book in any local college or university library.

Would you read such a book? You evidently have interest...and this book directly addresses your question, in much more detail than most folk would guess--we really do know quite a bit about vision. But, really, would you read this book?

Please do, and give us a report on what you have learned. It should be very enlightening for us as well as for you.

******

Oh...to add to the wonderful mentions of parallax, stereopsis, linear perspective, haze, interposition, texture gradient, accomodation and convergence, one final aspect of depth perception must be mentioned:

It is learned. For us to have a functional grasp of how far away something is, we must have experience with that distance, not just with our visual picture of it. Walk or run to something you have seen, throw a rock and see how far it goes...our perception of depth only gains meaning when we can combine our visual sense with feedback from the real world.

 

[Skeptical Greg]

How does a photon know how far it has traveled?


OH MY!!! Such penetrating questions!!! And one that no one has ever thought of before!! OH MY!!


Read the book...





A point awarded for posting this in R&P instead of Science...

 

[Acrimonious]

He wouldn't read it, just as surely as he didn't bother doing the simplest google search on vision or depth perception before posting this garbage.

This thread follows the typical Lifegazer M.O.

Since it goes against his philosophy, he arbitrarily dismisses it as incorrect and not worth reading or considering.

We could have the world's greatest authorities on stereoscopic vision and the brain's occipital lobe in this forum, detailing exactly how the eyes work and how vision is processed and interpreted for all to see. Lifegazer would ignore them, throw insults at them, and post more horribly inaccurate garbage based only on his "philosophy."

 

[Dancing David]

Let's conduct a thought experiment to get my point across: Imagine that you are blind. Now imagine that everyone around you has a water-pistol and is shooting water at you. Your skin might be able to tell you from what direction the water has come, but if we imagine that all incoming water has the same velocity (thus mirroring the same impact of the photons), then it appears impossible for the skin and/or brain to know what distance that water has traversed.
Hence, it would be impossible for the brain to create a 4-dimensional abstract representation of its external reality.

... Similarly, the same case applies for incoming photons. There is no way an incoming photon can impart the distance it has traversed to the eye/brain.
I suggest that this is evidence to prove that abstract awareness is not dependent upon an external reality.

So are you proving that the blind person doesn't get wet, or just the statement that the perception of wetness is dependant on the brain.

Lifegazer: How does this prove that perception is indepedant of the sense organs? Can you see through walls yet. (I know they only exist in your mind, but can you see through walls?)

The distance the photons travel is independant of the qualities of the perception.

When people talk about the photons from the sun traveling eight minutes to get to the earth, It is an educated assumption based upon the approximation of observed phenomena.

(The Pentagon will be really upset about you revealing how the Stealth bomber works!)

A+ for effort!
C- for originality.

 

[lifegazer]

First and formost, is stereoscopic vision. Most mammilian preditors have two eyes in the front of their face to facilitate stereoscopic vision. With stereoscopic vision, you can determine how far away something is. Simply aim both eyes at the object, and when the two images line up, you can take the angle the eyes are at, and the distance the eyes are apart, and calculate the distance. You can also calculate the distance of things that don't line up based on how far off they are from lining up.

This doesn't account for the size of the object, I don't think. For example, the moon and the Sun appear to be the same size. Thus the angle of the eyes would be the same for all objects that appear to be similar in size, regardless of their distance from the eyes. Correct? Which would make determining the distance of similar sized objects impossible unless you knew the width of those objects.

You don't have to pull out the trig book though, as a baby, your brain learned how to do all this stuff on its own.

Well the point would be that in order to construct an accurate depiction of external reality, using the angle of the eyes upon objects, that the brain would need to know trigonometry. I don't see how else the angle of the eyes could be useful to the brain, otherwise.
My question would then be: how can the brain know trigonometry before 'we' learn it?

Next would be related to stereoscopic vision, and that would be how far something moves in relation to other things when we move. This method is better when there are a great number of objects, when the objects are far away, or when you only have one eye.

Okay, I understand this. But we must recognise two things here:-
(1) In order that the brain construct an abstract-reality from external data, it must already understand how to use this data. For example, before constructing an abstract-reality from movement-related observations, the brain must already comprehend what you have just said.
(2) This method would would be very useful to identify which objects were nearer than others, but would tell us nothing of the actual distances which exist between eye and object. Hence, this method cannot be responsible for the accurate depiction of external reality we see within our awareness.

After that, would be blur. If something is blurry while you are staring at things far away, it is probably up close, and vice versa.

Err, okay. But again, the brain needs to understand this prior to constructing its abstract-reality and again, this tells us nothing of actual distances existing between objects.

Next would be atmospheric effects. Because our sky isn't excactly clear (more so on some days or another). You can determine by examining hue, tint, etc, how far away something is. This one really fools people when looking at pictures of the moon, because a mountain can be hundreds of miles away, and yet, because there is no atmospheric effect, we assume it is much closer.

I wasn't aware of this. Presumably, the brain must be in order to use such info.

Also, there is relative size. If we except something to be a particular size, we can use that size to determine how far away something is based on how small it apears.

Err, this doesn't sound too accurate either.

Many of the methods you mentioned wouldn't create an accurate and universal abstract-reality.
I could buy the angle of the eyes method as long as we acknowledge the brain's capacity to do trig, prior to creating that reality. But since the brain doesn't know the size/width of the object, nor the length traversed by the photons, knowing the angle of the eyes wouldn't seem to be of too much use.
Also, we all have differently-spaced eyes which grow further apart into adulthood. Are you suggesting that the brain takes account of this as it gathers its info?

 

[lifegazer]

I can see that the eye/brain could fathom that some objects were closer than others, and some further than others. But how does it get an accurate picture of events? None of the replies here have answered that question.

 

[Skeptical Greg]

This doesn't account for the size of the object, I don't think. For example, the moon and the Sun appear to be the same size.

Urrh, uhhh, Doh... People did think they were the same size untill we learned better...




Read the book..

 

[Skeptical Greg]

I can see that the eye/brain could fathom that some objects were closer than others, and some further than others. But how does it get an accurate picture of events? None of the replies here have answered that question.

Read the book...


Really, a lot of people thought about this before you asked..

 

[Yahweh]

This doesn't account for the size of the object, I don't think. For example, the moon and the Sun appear to be the same size. Thus the angle of the eyes would be the same for all objects that appear to be similar in size, regardless of their distance from the eyes. Correct? Which would make determining the distance of similar sized objects impossible unless you knew the width of those objects.

Not at all.

Take two objects. One object has an area of 1 square meter, the other object has an area of 4 square meters. Put the first object at distance of 10 meters away, put the other object at a distance of 20 meters away.

Hopefully, I've done my math right, but as predicted by the Inverse Square Law, each object will appear to be the same size.

When you move to the right about 5 meters, the objects in your field of view "move" as well. You'll notice that the smaller object moves a considerable distance more than the larger object, although they do in fact look the same size.

I wont detail the math, but it is very much possible to derive information regarding the height, width, and distance away those objects are.

This is called "Parallax", its one of the many visual clues.

You dont even need binocular vision, the same monocular clues still give you the information regarding the distance of those objects.

Well the point would be that in order to construct an accurate depiction of external reality, using the angle of the eyes upon objects, that the brain would need to know trigonometry. I don't see how else the angle of the eyes could be useful to the brain, otherwise.
My question would then be: how can the brain know trigonometry before 'we' learn it?

We dont know the math, but we understand the concept. The brain does not need to learn trigonometry, it makes use of visual cues before the concept is even understood.

I dont need to be told that things further away appear smaller.

Most people are unable to determine the height or distance of an object, human judgement alone is very inaccurate. The math makes the guesstimation much more accurate.

Okay, I understand this. But we must recognise two things here:-
(1) In order that the brain construct an abstract-reality from external data, it must already understand how to use this data. For example, before constructing an abstract-reality from movement-related observations, the brain must already comprehend what you have just said.
(2) This method would would be very useful to identify which objects were nearer than others, but would tell us nothing of the actual distances which exist between eye and object. Hence, this method cannot be responsible for the accurate depiction of external reality we see within our awareness.

Err, okay. But again, the brain needs to understand this prior to constructing its abstract-reality and again, this tells us nothing of actual distances existing between objects.

I wasn't aware of this. Presumably, the brain must be in order to use such info.

Err, this doesn't sound too accurate either.

Many of the methods you mentioned wouldn't create an accurate and universal abstract-reality.
I could buy the angle of the eyes method as long as we acknowledge the brain's capacity to do trig, prior to creating that reality. But since the brain doesn't know the size/width of the object, nor the length traversed by the photons, knowing the angle of the eyes wouldn't seem to be of too much use.
Also, we all have differently-spaced eyes which grow further apart into adulthood. Are you suggesting that the brain takes account of this as it gathers its info?

Well, I dont think its necessary for me to detail all the different ways we calculate distances. Just know that humans have no handicap in judging the distances of objects, there are a great number of binocular and monocular cues and precise mathematics which give us all the information we need.

 

[Upchurch]

This doesn't account for the size of the object, I don't think. For example, the moon and the Sun appear to be the same size. Thus the angle of the eyes would be the same for all objects that appear to be similar in size, regardless of their distance from the eyes. Correct? Which would make determining the distance of similar sized objects impossible unless you knew the width of those objects.

Objects like the moon and the sun are problematic in that there is no point of comparison, there isn't enough experience to make the judgement. When one sees a car at a distance, we have a rough concept of the size of a car, so that not only can we use steriotopic vision but contextual clues as well.

Well the point would be that in order to construct an accurate depiction of external reality, using the angle of the eyes upon objects, that the brain would need to know trigonometry. I don't see how else the angle of the eyes could be useful to the brain, otherwise.
My question would then be: how can the brain know trigonometry before 'we' learn it?

Trial and error. Babies, especially young ones, have a great deal of difficulty understanding distance. The brain isn't actually learning trigonometry in terms of sin, cos, tan, etc. It's learns that the more one has to cross one's eyes in order to focus on an object, the closer it is.

Okay, I understand this. But we must recognise two things here:-
(1) In order that the brain construct an abstract-reality from external data, it must already understand how to use this data. For example, before constructing an abstract-reality from movement-related observations, the brain must already comprehend what you have just said.

Or, as I said, the brain must learn using trial and error. I'd recommend reading some young child development books. I found it one of the most fascinating aspect of psychology.

(2) This method would would be very useful to identify which objects were nearer than others, but would tell us nothing of the actual distances which exist between eye and object. Hence, this method cannot be responsible for the accurate depiction of external reality we see within our awareness.

No one can "eyeball" a distance with absolute accuracy. Even long time carpenters need a tape measure. I'm not sure I understand what the point is.

I could buy the angle of the eyes method as long as we acknowledge the brain's capacity to do trig, prior to creating that reality. But since the brain doesn't know the size/width of the object, nor the length traversed by the photons, knowing the angle of the eyes wouldn't seem to be of too much use.
Also, we all have differently-spaced eyes which grow further apart into adulthood. Are you suggesting that the brain takes account of this as it gathers its info?

Practice, practice, practice. We do it every waking moment of our lives and we get quite good at it. Not perfect, but pretty good.

 

[Upchurch]

I can see that the eye/brain could fathom that some objects were closer than others, and some further than others. But how does it get an accurate picture of events?

How is any understanding of a specific situation made better? Lots of data points. The more observations taken, the more accurate the picture. Being able to walk up to the object and back again would also help.

 

[RussDill]

(Lifegazer, if this is a joke, or a troll, please tell me now)

This doesn't account for the size of the object, I don't think. For example, the moon and the Sun appear to be the same size. Thus the angle of the eyes would be the same for all objects that appear to be similar in size, regardless of their distance from the eyes. Correct? Which would make determining the distance of similar sized objects impossible unless you knew the width of those objects.

No, I think I need to draw a picture, as stereoscopic vision has no hope of determining which is farther, the sun or the moon, and also, stereoscopic vision has nothing to do with the size of an object. An extreme example is to look at your nose, your eyes turn inward to a great angle. If you look at anything far away, your eyes are essentially straight, anything else and it is a variation of that angle. And again, your brain can also guess the distance of objects that don't line up.


Maybe a neato little game would help

http://www.vision3d.com/frame.html

3d glasses are a good example too

http://www.scottandmichelle.net/scott/myshots/images/index-04-6.html

put on 3d glasses, and boom, instant 3d vision, and nothing about the time it takes for photons to get to you. Notice in this picture that the two cameras were angled together so that the 1 on the D4 is in focus, everything else generates two images, which are filtered through to the left and right eye with the use of red and blue filters.

Well the point would be that in order to construct an accurate depiction of external reality, using the angle of the eyes upon objects, that the brain would need to know trigonometry. I don't see how else the angle of the eyes could be useful to the brain, otherwise.

My question would then be: how can the brain know trigonometry before 'we' learn it?

It doesn't need to know trig unless you want an exact distance. The brain isn't concerned with exact distances. It is like throwing a ball to someone, you don't need to know trig, your brain guesses. After each subsequent throw, your brain gets better at guessing through a process called learning.

If you have ever taken care of small children, you'll notice that they have not fully developed these skills, their sense of scale may be so far off, that they are afraid of being sucked down the drain in the tub.

Okay, I understand this. But we must recognise two things here:-

It is the same thing as stereoscopic vision, but performed simultaneously. This is also the method we use to accurately calculate how far away a star is. We take a picture of it, wait 6 months, and take another picture.

(1) In order that the brain construct an abstract-reality from external data, it must already understand how to use this data.

Says who? Clearly the brain is structured in such a way to facilitate certain areas performing certain tasks. Perhaps at some level, the brain is hardwired with certain concepts necessary for vision, but neural networks do learn by trial and error, not by understanding how something works.

For example, before constructing an abstract-reality from movement-related observations, the brain must already comprehend what you have just said.

Who says? Children learn to play catch just fine without understanding gravity or differential equations. I can sit you down and have you start playing a game, and you'll start getting better at it before you understand it. The brain is very good at learning through trial and error.

(2) This method would would be very useful to identify which objects were nearer than others, but would tell us nothing of the actual distances which exist between eye and object.

Actually it does, it is just more difficult, a person with the use of only one eye gets very good at this method.

Hence, this method cannot be responsible for the accurate depiction of external reality we see within our awareness.

Very good, that is because it is a combination of all the factors I have listed (as well as the additional ones listed by other posters)

Err, okay. But again, the brain needs to understand this prior to constructing its abstract-reality and again, this tells us nothing of actual distances existing between objects.

No it doesn't, again, trial and error, also, it is not necessary for the blur effect to tell us exact distances, it is just another visual clue.

I wasn't aware of this. Presumably, the brain must be in order to use such info.

no, it is something learned over time.

Err, this doesn't sound too accurate either.

Why not? It is an excellent clue that combines nicely with haze to provide a very good system of guessing the distances of far away objects.

Many of the methods you mentioned wouldn't create an accurate and universal abstract-reality.

Not alone, that is why they are combined.

I could buy the angle of the eyes method as long as we acknowledge the brain's capacity to do trig, prior to creating that reality.

Again, not necessary, since each distance is related to an angle. After learning what distance is associated with each angle after trial and error, the brain is can discern distance, no trig necessary.

But since the brain doesn't know the size/width of the object, nor the length traversed by the photons, knowing the angle of the eyes wouldn't seem to be of too much use.

Sigh, I take it you never took trig either.

Take the eyes (2 inches apart), point a and point b, and something in the distance, point c. The eyes in this simple example both point to the object, point c, so they form an iso...er, sorry, a tringle with 2 equal angles and 2 identical sides. Name the angles A, B, and C to go along with the points. Split the triangle in half at the point right between the eyes, and make point d. The angle at point d, D, will be a right angle. So now we have a right triange, a, d, c. The side, ad is 1 inch. Now, we have angle A, and the length ad, that is enough info to find the length dc.

tan A = dc/ad

so, dc = ad * tan A

pretty simple, the distance is proportional to the tangent of the angle. So your brain does not need to learn trig, just the shape of the tangent function. See how there is no reference to the size of width of the object? Nor is it necessary to know how far photons went.

Also, we all have differently-spaced eyes which grow further apart into adulthood. Are you suggesting that the brain takes account of this as it gathers its info?

Yes, why? The same thing applies to everything else, from walking to throwing a ball. Our brain can even take into account a change in gravity. Throwing things on the space shuttle takes quite a lot of learning, but once learned, it can be done.