Humans tend to form whole perceptions from partial images.
When information about a physical object is hidden from view,
or assumed to be hidden from view, humans mentally round up
the information and perceive the whole thing, or at least the
whole thing as defined by their minds. This is part of the human's
natural ability to quickly interpret limited information, an
ability essential to making the snap judgments needed to get
through life. This mental extrapolation is a great intellectual
skill. In cases, however, the filled in information is illusory,
a product of the mind not reality.

Those familiar with American history don't need a full view to
identify this man as former US President Teddy Roosevelt. If
I also had hid all of his legs or his hands, it wouldn't have
hindered identification.

It's not just how much but what information is visible that is
important. Though from this information,a viewer might be able
to make an interesting guess about the man. Banker? Businessman?
Wealthy, world traveler? Big city Boss? Some of these guesses
aren't too far off.
Read the following two texts:
They are both the same text, but the second
text has the ruler removed from the last line. Your original
reading of the last line was what you expected. If the ruler
had never been lifted, you likely would have lived your life
believing that last line said 'I Love You.'
It is important to note that humans never see the entirety
of an object, any object. Not only are things like coffee cups
and sticks and tree branches partially visibly obscured by overlapping
other objects, but we can never see all sides and parts of an
object at once. Even with an apple you've turned over in your
hands, you can't be sure whether its fresh or rotten in the core
until you bite or cut it apart. Humans live and learn in an environment
where information is always obscured or otherwise hidden from
view.
Humans never have a wholly objective perception
of an object, in part as they can't see the entire object. The
perception is formed in part by what is seen and in part by expectations,
memory, personal experience and guessing. Your perception of
this ball is also part emotional and aesthetic, influenced by
personal experience and like or dislike of the game ... Your
perception of an unchanging object changes as you do.
It is also important to note that many physical qualities of
and between objects are identified by obscured or otherwise hidden
visual information. For example, distance is in part is judged
by objects overlapping each other and things becoming harder
to see over distance. Thus, obscured visual information both
helps and hinders our identification of objects. When something
is very far away, the lack of detail (very small and blurry)
serves to both help us judge distance and prevent from identifying
the object. A closed closet door shows us that the door is in
front of the things in the closet, but prevents us from knowing
what are the things in the closet. Lack of information is both
lack of information and information.

Many objects are defined by their depth, height, length, opacity
and parts. That some parts of this table visually obscure other
parts help the viewer identify it as at able.

Overlapping helps show us that the scrambled eggs are on the
plate and the trees are closer than the buildings.
Visual identification requires comparison and contrast
On this black square is smaller black shape.
What is the smaller shape? Without color
contrast, it's impossible to answer.
People like to claim they can perceive and judge an object
on its own-- leave that namby pamby relativism to the bleeding
hearts. However, visual identification requires comparison to
other things. The edges of the above scrambled eggs helping is
identified because beyond is the whiteness of the plate. With
a black square against a matching black background, the viewer
optically sees the square but does not know it's there. When
the background is changed to a different color, then the viewer
identifies the square. Even though the square is always in open
view, viewer identification requires contrast.
Further, the images in front of you are compared to the images
in your mind. You identify a dog, because the image matches up
with the dog in your memory. If the dog is at a distance, you
guess size by using your memory of dogs and your memory of the
sizes of objects this dog is near (trash can, basketball).
An object is not only identified by what surrounds it, but
is defined by what is around it. Beyond the edge of a table is
air-- the difference between air and wood defines the edge. Beyond
the surface of a ball is air or dirt or grass. Beyond the edge
of a square is something different. Beyond this is that. A cat
doesn't exist without different stuff surrounding it. Even studying
something in a vacuum involves in comparison and contrast
to the vacuum.
cycleback.com................broken glass
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