1. PRINCIPLES OF VISUAL PERCEPTION
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The world we perceive is as much “given” as it is constructed.
Unlike a camera, we are more than passively involved in the way we perceive the
world.
It follows then, that even when observing the world through a camera lens, the
'snapshots' or movies we take reflect our active interpretation of the world.
Let us first touch upon on human vision as distinct from other animals.
'The world' which we often regard as objectively 'out there' is experienced in very
different ways by other creatures.
In human beings sight is the dominant perceptual sense. It therefore, dominates
the way in which we 'see' the world. It even dominates our descriptive vocabulary.
Although we do know that eyes differ in the animal kingdom, and that different
animals vary in their reliance on vision, we don't know how other creatures see
the world.
While most mammals live in more of a world of scent than of sight, we along
with other primates rely more on sight. Birds and insects also are more sight
reliant.
Differences in the visual mechanism are also striking within the animal kingdom
namely: the shape of the eye, its acuity (focal distance), the field of vision,
accommodation (adjustment of focal length), position of the eyes and their ability
to rotate etc.
Different animals perceive color differently. Some perceive more colors than
others. Some perceive color beyond the human visible spectrum into the infrared
and ultraviolet ranges.
Some animals are more adept to seeing in virtual darkness, while others see well
in “blinding” brightness.
Different creatures vary in the amount of the brain that is devoted to vision. Over
half of the brain of the octopus and the squid is devoted to vision.
 The world, then, is 'seen' in different ways by different creatures.
 While people rely heavily on vision, we do not always 'believe our own
eyes' - we know that a pencil in a glass only appears to be bent, that the
moon only appears to be larger when it is near the horizon and that there
are such things as optical illusions.
 As a species, we seem to be driven by a desire to make meanings:
Perhaps more than Homo sapiens, we should reference ourselves as
Homo significans - meaning-makers.
 This fundamental concern underlies the process of human visual
perception.
 As touched upon last Monday, people prefer order to chaos, because it is
more accessible. It is more convenient to find your mail in a pigeonhole
than in a mailbag.

2.  Similarly to our desire to organize the external world in order to make it
more accessible, we tend to organize the information we perceive into
coherent and cohesive units, at the moment of perception.
 This type of organization is automatic and subconscious.
 The most common type of subconscious organization is that of analogy
or comparison.
 If we can find similarity between two perceived entities , we can place
them both in a single category.
 As more analogous information is perceived, comparisons between
“more similar” entities warrants further categorization (smaller pigeon
holes).
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The more we are capable of, and the more we allow ourselves, to discriminate, the
greater the number of categories we form. The less we care to discriminate, the
smaller our world is.
Categorization is a key 'top-down' process which is involved in perception.
Categories simplify.
Categorization has a number of functions: The cost of these advantages is a loss
of particularity and uniqueness in perception and recall.
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it makes complexity manageable;
it speeds up recognition;
it reduces effort and learning;
it makes the most of past experience;
it enables the inferences about further attributes
(going beyond what is 'given');
it makes events predictable;
it supports systematization;
it bonds social behaviour (providing shared
frameworks);
it tailors the world to our purposes;
it makes the world seem more meaningful.
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For Romantics, it is also regarded as inducing a sense of distance from the world.
The way we categorize phenomena seems to be a 'natural' 'reflection of reality',
leading us to forget the role of categorization in constructing the world.
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Probably the most well-known example of the cultural diversity of categories is
that Eskimos have dozens of words for 'snow' - an assertion which is frequently
attributed to Benjamin Lee Whorf. Actually, Whorf seems never to have claimed
that Eskimos had more than five words for snow (Whorf 1956, 216). However, a
more recent study - not of the Inuit but of the Koyukon Indians of the subarctic
forest - does list 16 terms for snow, representing these distinctions:

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snow
deep snow
falling snow
blowing snow
snow on the ground
granular snow beneath the surface
hard drifted snow
snow thawed previously and then frozen
earliest crusted snow in spring
thinly crusted snow
snow drifted over a steep bank, making it steeper
snow cornice on a mountain
heavy drifting snow
slushy snow on the ground
snow caught on tree branches
fluffy or powder snow (Nelson 1983, 262-3)
 When we are tired, we tend to discriminate less, and as a result we make
fewer associations between perceived entities. Generally, quantitatively,
we “create” less. Qualitatively, however, we may associate things that
might otherwise pass us by for moving too quickly, or for taking things
for granted.
 People on drugs at times seem to have some unique creative moments.
Often, when re-examined, they seem more as the “mastery of the
obvious”
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There are several types of associative mechanisms that can be “associated” with
creativity.
 Faced even by 'meaningless' patterns the mind restlessly strives to make
them meaningful.