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Depth Perception or Depth Conceptualization?

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Recently, I read a transcript taken from one of Binswanger's lectures in which he defends perception from certain skeptical attacks against it.  He calls perception "inerrant" which means that the information that you do perceive cannot be wrong because it is silent and cannot play tricks on you because it does not tell you anything.  The concepts that you form based on perception can be wrong, according to my understanding of Binswanger.  At first, I was in complete agreement with this but then I thought of the example of depth perception.  With modern 3D glasses (either passive or active), it seems to me that your eyes are truly deceived because they get sensory input that leads to you perceiving a 3D object that is not really a 3D object at all, just a projection on 2D screen.  I see this as significant because if depth perception can be wrong, then so can all perception, which conflicts with Oist epistemology's teachings that humans are infallible at the perceptual level.  The only way that I could think of this not invalidating the sense of sight is if depth is not something that is perceived, but instead is a concept formed based on perceiving entities that have a spatial relationship to you.  I know that Peikoff did mention that Space is a relational concept and  refers to a relationship between entities that exists in reality.  And this reinforces my thinking that depth cannot be perceived because depth is like space and there is no such thing as the space between two entities to perceive in the first place.  There is only a relationship between entities that exist in the universe.  I'm not sure about this though and I hope to learn what anybody else's thoughts are on this.

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The light hitting your eyes gives you an image that looks like a 3D object.  That is on the level of perception and is true.  Whether it really is a 3D object is on the level of interpretation, and there it is possible to make errors.  This is not really different from other cases that have been used to attack the senses, such as a stick partially in water looking bent.

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There is a terminological shift “out there”, where certain kinds of inferences based on perception are also labeled perception: but perception is non-inferrential, it is direct. In fact, it is well known that depth perception is very inferential, to the point that I suck at gauging distances and my brother is pretty good at it. The problem is that the term “perception” has been used to cover a wide range of cognitive actions which includes high level inferences. When Objectivism speaks of “perception”, we mean that part of cognition that is metaphysically given, not man-made. The metaphysically-given is unavoidable: if your eyes are open, you are conscious, and there is a ball in front of you, you must see the ball and cannot chose to not see it – perceiving it is metaphysically given. The inference that it is a ball as opposed to some other thing is man-made and optional. In concluding that perception is inerrant, that does not mean that inferences about the cause of an instance of perception are also inerrant: in other words, dept perception isn’t “perception” in the sense that Objectivism uses the term.

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Eyes can't be deceived because eyes are just organic mechanisms.  The technology of 3D presentation is based upon understanding the cues that cause the perception of three dimensionality in vision (mainly stereoscopic perspective) and then replicating those cues 'well enough'.  The eyes are relaying to your brain what is presented to them.   This is just another type of illusion, not a special case.

Your issue is very much similar to debating if a thing is truly red or merely painted red.  The appearance of redness is genuine in either case, and so is the appearance of three dimensionality in your example where the 3-Dness is 'painted on'.  That appearances can be deceiving is long known.

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@Grames you mentioned

“Your issue is very much similar to debating if a thing is truly red or merely painted red.  The appearance of redness is genuine in either case, and so is the appearance of three dimensionality in your example where the 3-Dness is 'painted on'.  That appearances can be deceiving is long known.

So here is what I find troubling about your statement.  In your example, there is actually something about the paint that contains physical properties that I perceived as red.  It EXISTS and is there for me to perceive it.  And it was placed on the object which also EXISTS and is there for me to perceive it.  I understand this situation.  But I don’t think my example should be granted an equal status and I will try to argue why.

In the case when you are focusing on a 2D screen, THERE IS NO THIRD dimension so therefore it follows THAT THERE SHOULD BE NO WAY TO PERCEIVE it.  You can’t perceive something that doesn’t exist.  You only may perceive something else and you might think that that something else is something, in which case you would be perceiving something but mistaking it for something else.  Although this whole situation with 3D glasses is making me doubt what I wrote in my previous sentence so I am actually interested in what you think about being able to perceive something which does not exist.  For example, if we did not live in 3D universe, only 2 dimensions, would it even be possible to perceive or even misperceive a third dimension if a third dimension didn’t even exist?

I would assume that it would be impossible and I based some further thinking about this situation on this assumption and it gave me another idea.  Even with 3D glasses, whatever object you are perceiving, even if it is a 2D screen, is still located a certain depth away from you.  And it might be possible that you can misperceive that depth and misperceive it varyingly (by “varyingly” I mean certain parts of it appear closer than others) under the right circumstances.  So I read a little bit about what those circumstances might be and I stumbled onto stereopsis.

So it turns that there are multiple mechanisms by which we perceive depth, with a major one being by having two eyes spaced a certain distance apart.  In normal vision, because the eyes are spaced a certain distance apart, your eyes get two slightly different images delivered to them by light and light is incident at slightly different angles.  Your mind than takes those images and integrates them into sensations.  Then it integrates those sensations into a perception.  And it actually uses the two different images to perform the integration to perceive depth.  And it is at this point that I have another doubt and it relates to what to DavidOdden stated about the “metaphysically given.”

I find myself asking “Is depth metaphysically given?”  If depth is perceptual, then it has to be “metaphysically given.”  But it just might be so that only objects are metaphysically given.  This is also why I titled my post the way I did.  I am starting to suspect that “depth perception” might instead be a first-level concept and I would be very interested in your response to this thought.  Besides the question about depth, another reason that I am thinking that “depth perception” could be a first-level concept is that we all make an implicit assumption (and no assumptions are supposed to be involved at the perceptual level of consciousness) that we do not think about when we look at any object.  That implicit assumption is also how the makers of 3D glasses trick us into perceiving a 3rd dimension that IS NOT THERE.  We assume that we are looking at the SAME OBJECT WITH BOTH EYES.  This turns out to be an extremely significant and overlooked implicit assumption because passive 3D glasses actually filter two types of light that are coming from DIFFERENT LOCATIONS from a screen.  One lens blocks out one type of light so your eye never sees it and the other lens blocks out the other type of light so your other eye never sees the light the former eye sees.  THIS IS HOW YOU GET TWO DIFFERENT IMAGES DELIVERED to your eyeballs.  You’re actually looking at two different pictures (objects) and you don’t know it.  Active 3D glasses create an almost equivalent situation but not exactly the same.  They either function as a screen or synchronize with a T.V screen to alternate back and forth between images that your right and left eyes would see if you were not being deceived.  The TV shows an image intended for your right eye and your left lens darkens completely (so your left eye never sees the image intended for your right eye) and a split-second later the TV shows an image for your left eye and your right lens darkens completely (so your right eye never sees the image intended for your left eye) and this happens so fast and frequently that your brain can’t tell the difference.  It’s a slightly different situation but it achieves the same end result, you get two slightly different images delivered to your eyeballs that your eyes would not see if they were both simultaneously looking at one image on a screen, but THAT THEY WOULD SEE if you were looking at the object in real life.  It’s almost like your mind is performing a trigonometric triangulation calculation with an object being one vertex and your two eyes being the other two vertices…

The bottom line is that those glasses deliver two slightly different images to your eyeballs and your brain integrates them into one whole 3D perception. 

The last question I am hoping to get your response on which is slightly tangent from this OP (but not too tangent) is the following:  Is there a spatial relationship that exists between entities in reality independent of the mind?  And if it does exist independent of the mind, is it “metaphysically given” (meaning can it be perceived?) or is it just metaphysically real and conceptually identified?

I know Peikoff said that “Space is a concept” but he did mention that it refers to relationship between entities so I am thinking that the relationship it refers to has to exist in reality, right?

The reason I ask this is because I think depth perception might be based on the conceptual identification of a spatial relationship between “metaphysically given” entities.  I don’t know about depth, but I suspect that you can at least know based on observation that we live in at least a 2D universe because you can visually perceive at least in 2D (because the images you get even of the real world are in fact in 2D) and you can geometrically conceptualize that you can two perpendicular line segments between the entities you see that would also determine two axes (or two dimensions of space).  I think connecting these line segments and understanding how they determine two axes of space could be the very act of conceptually identifying the spatial relationship between entities. And I think that the way that you know that there is a 3rd Dimension is by connecting line segments from the entities that you see in 2D TO YOURSELF (since you yourself are self-aware and are therefore also at least a “metaphysically given” entity).  When you connect this line segment to yourself, I think you have conceptually correctly identified a 3rd dimension of the spatial relationship between you and every other entity that exists.  I think by going through this geometric proof you can at least know that there are 3 dimensions and depth has to exist as a result of this conclusion being true and it may exist in any quantity, but it must exist in some quantity.

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@Grames I'm sorry I have one more question related to misperception.  Let's say for example that I misperceive a temperature, do I have a right to claim that a temperature exists in some quantity even though I haven't perceived it?  Or if I misidentify a watercup as a ball, do I have a right to claim that something exists?  This kind of relates to my thinking about "depth perception" and it being distorted.  If your perception is distorted, you have misperceived something (some object) but I think you must have at least done something right if you were able to achieve the form of perception that you did.  And I'm wondering are there any valid claims that you can make based on misperception like the examples I gave?

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I think it would be useful to quote part of How we know, from the chapter on perception

Quote

The perceptual data are not wrong or mistaken — but they can be misleading : a naïve observer is likely to conclude: “This stick is bent.” If he does, it is that conceptual judgment, not the seeing, that is mistaken

 

In the bent-stick “illusion,” what we see is the way a straight stick looks when semi-submerged in water. The image on the left is, after all, a photograph. The camera does not lie, and neither do the eyes.

 

 

“Perception” includes: seeing, hearing, touch, smelling, tasting, and awareness of things going on in our bodies (proprioception). “Perception” does not include: association, expectation, prediction, classification, inference, propositions, intellect, reason, interpretation, judgment, thought.

           There is a linguistic signal in English for the difference between the perceptual and the conceptual: the locution “seeing that” always indicates a judgment, never just perception. You see a tree. But to see that it is a tree is “seeing” in only a metaphorical sense. To see that something is a tree is to go beyond the perception to subsume what is perceived under the concept “tree.” Likewise, we are not dealing just with perception if we see that the tree is big, that the tree is old, that its leaves are green. Perception includes only seeing the big, old, green-leafed tree.

When you say that “there is no third dimension so therefore is follows that there should be no way to perceive it”, you’re speaking of a “perceive that” and not a bare “perceive”. You perceive the thing. Period. You do not perceive a dimension – a dimension is a high-level spatial concept, not an entity. You only perceive entities, and conceptually reason to conclusions about the nature of the entity.

 

Edited by DavidOdden

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Touch is inherently 3-D, and the awareness of your own body is 3-D.  Whatever the concept "space" refers to that may make it a higher than first level concept in physics or geometry, we don't need that to know height, width and depth all exist at the same time as attributes of the same entities (ourselves, the things we touch, and the things we see).  

In Kelley's The Evidence of the Senses he did have to allow that perceiving can include acquired skill in discrimination.  Certainly it is the case that infants require time and practice before they can learn to focus their eyes and reliably gauge whether something is within their reach or not by visual inspection alone.  Still greater skill is required to be professional athlete throwing or catching balls or to be skilled with a firearm.  That skill includes so-called eye-hand coordination where control of one's own body (not just hands) is automatized through practice to a high degree. 

What is the epistemological given is product of the senses, that means the final product after the full causal chain of the senses has acted upon the stimuli given to it including those actions of relatively sophisticated integration incorporating acquired skill that result in (for this example) depth perception.   So long as what went on was automatic, meaning beyond the control of conceptual consciousness, it is taken as external to conceptual consciousness.  What is external to conceptual consciousness is the given.  What was given was both the percepts and the means of perceiving.

22 hours ago, ReasonFirst said:

The bottom line is that those glasses deliver two slightly different images to your eyeballs and your brain integrates them into one whole 3D perception. 

Yes, those two images and the carefully calibrated differences between them are the cause of the 3-D effect.  So that is what is really there, it is not a case of perceiving something not there.  Identity and causality are responsible for the 3-D effect.

 

22 hours ago, ReasonFirst said:

Is there a spatial relationship that exists between entities in reality independent of the mind?  And if it does exist independent of the mind, is it “metaphysically given” (meaning can it be perceived?) or is it just metaphysically real and conceptually identified?

Yes (see my first paragraph), and it is both metaphysically given and via the senses epistemologically given.  Not everything that is metaphysically given is epistemologically given; for example atomic theory (even Democritus' version) requires a conceptual framework.  Knowing that things move is given; no theory of motion is a given.

For what its worth I offer this:  Don't get hung up on vision as your only sense modality for thinking about space.  Remember that non-human consciousnesses such as bats navigate through three dimensional spaces (sometimes the very same three dimensional spaces where humans are present) largely depending on their hearing.  

22 hours ago, ReasonFirst said:

Let's say for example that I misperceive a temperature, do I have a right to claim that a temperature exists in some quantity even though I haven't perceived it?  Or if I misidentify a watercup as a ball, do I have a right to claim that something exists?  This kind of relates to my thinking about "depth perception" and it being distorted.  If your perception is distorted, you have misperceived something (some object) but I think you must have at least done something right if you were able to achieve the form of perception that you did.  And I'm wondering are there any valid claims that you can make based on misperception like the examples I gave?

There is no misperceiving, only misidentifying.  You can be certain something caused your percept if you have a conceptual grasp of identity and causality.  But you don't necessarily know what caused your percept.  There is such a thing as a "normal range" within which the senses are most effective, which is daylight on the surface of planet Earth.   If the prevailing conditions for perceiving are unusual (dim light, monochromatic color source, dipping your arm in an ice bucket then a different bucket, etc...) then seeing or even feeling is not believing.  

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