1. We see what we want to see.

2. Group Name: We are the Aztecs
Eddie Kennedy
Student No. 10003871
Niall Ryan
Student No. 13113054
Jamie O’ Dwyer
Student No. 13073826
Paul Murphy
Student No. 09006031
Date: 17/04/2014

3. In this report on how we perceive our world through sensation and perception, we decided to explain
how we perceive our world through our eyes and through the world of magic and magicians.
Before we start to analyse how we experience our world we believe it would be appropriate to try and
define exactly what Sensations and Perceptions are. Also we will explain how by using Gestalt
Principles we have come to understand perception. We will hope to describe the process of perception
and how our experience shapes our perception this through the art of magic and deception.
When we observe nature we see what we want to see, according to what we believe we know about it
at the time. Nature is disordered, powerful and chaotic, and through fear of the chaos we impose
system on it. We abhor complexity, and seek to simplify things whenever we can be whatever means
we have at hand (James Burke).
Sensations can be defined as the “passive process of bringing information from the outside world into
the body and to the brain.” Perception can be defined as “the active process of selecting, organising,
and interpreting the information brought to the brain by the senses.” In order for us to experience,
these two must work in tandem, so what actually happens? Firstly a sensation transpires where our
sensory organs absorb energy from some sort of physical stimulus in the environment. The sensory
receptors will then convert this absorbed energy into neural impulses which will then be sent to the
brain. At this point our brains bring together the collected data and translate it into something which is
meaningful to us. But the question at this point is how do we know which information to use and
which information is useless to us. We use selective attention which in the main is influenced by our
own motivations. Selective attention is the process of discerning the valuable and lesser information
we need to experience. So say for example employees of Google are at a meeting and someone is
giving a talk, the employees should be listening to what the speaker is saying. But people outside in
the corridor strolling by, may be looking in to see who is giving the talk and not necessarily what the
talk it is about. It is said that our past experience and our culture have a major influence on how we
perceive the world. An example would be a tribe who spent their entire lives in the forest had no sense
of depth perception. So when foreigners brought them out of the forest into the open and they spotted
an animal in the distance. The animal looked small to the tribesman but when they got close to the
animal the tribesman was stunned to see that the animal was in fact large and not miniature as he
thought he perceived it to be. So because the tribesman had never been out in the open before his past
experience had thought him nothing of depth perception.
The Gestalt principles help us to organise our visual perceptions so that when we see a magician on
stage we can determine that the magician is figure and the stage is ground. This principle is called
figure/ground. Pragnanz is the principle of grouping things together. Our brains perceive things in
patterns and once we perceive a pattern we are inclined to pay less attention to the details. So when a
magician shows you his cards and you perceive the pattern red/black/red/black your brain will not
normally notice other details only what the magician tells you to notice and this is how you will be
deceived. In an example of this online called the PowerPoint Card Trick you are asked to pick a card
from a selection of six cards in the pattern red/black/red/black and remember your chosen card. The
next slide says that it will now make your card disappear. The next slide shows 5 cards, Abracadabra
your card does disappear and you are amazed. But what actually happened was that all the cards were
changed and because you only noticed the pattern and not the details you were tricked.
To relate this back to what actually happens internally we will try and describe part of the perceptual
process. When we begin to process an object in this case a set of cards we are at the pre-attentive
stage where we break the objects into features such as colour, size, amount and so on. Then we move
to the focused attention stage where all the specific features of the cards are united and we perceive
the whole object as a set of cards. Of course we would not be able to perceive magic like this without
the aid of our eyes. The process of seeing or vision should be explained with a description of the
structure of the eye. In order for us to see the cards in the above trick we need the retina which is
located at the back of the eye. The retina is responsible for sharp central vision and is essential for
visual detail it is responsible for 80% of the eyes focusing power.

4. Another Gestalt principle the principle of continuity is something that magicians exploit when
performing a lot of their tricks. An example of this particular trick is where a magician shows a ball to
the audience; throws it in the air three times and on the third throw the ball vanishes into thin air. How
does he do it? When we see the ball being thrown in the air we are instantly following whatever
direction we are led; in this case we see the magician’s hands and eyes looking up and we follow suit.
After each throw we recognise the pattern and we expect the next throw to be the same but no the
magician keeps the ball in his hand. This principle really outlines how we are so lazy when it comes
to perception. We know from bottom-up processing that the last time the magician threw the ball in
the air it was still there so why would we think differently on the third throw. If we saw the trick
being done before or a friend had shown us how the trick was done then we would be using top-down
processing which is based on knowledge. Perceptual expectancy yet another Gestalt principle says
that our biological makeup our past experiences and our culture will undoubtedly sway our
perceptions of the world we see before us. This top-down processing helps us to organise the different
sections of the world into something we can comprehend into something called Perceptual sets. A
good example of this would be “let's say you are driving across the desert. You are very low on gas.
Finally, you see a sign approaching. On it are the worlds FUEL AHEAD. You relax, knowing you will
not be stranded. But as you draw nearer, the words on the sign become FOOD AHEAD. Most people
have had similar experiences in which expectation altered their perceptions. Perceptual expectancies
are frequently created by suggestion”. (Coon, Dennis. 1989)
This brings us onto how our culture influences our perception of the world. Things like emotions,
biases and motivations are deeply embedded in culture. Culture gives us rules it gives us guidelines on
how to live, it provides structure. Where you live in the world can have a major influence on how you
perceive. Research suggests that in Eastern cultures the dominant structures on how to live are to find
a balance between negative and positive emotions. Whereas in the Western world the negative
emotions are to be kept hidden and the positive are to be out in front at all times. Bias and motivation
factors tend to influence our perceptions both positively and negatively. Someone who has an
egocentric bias would have a better perception of themselves than maybe others would, this can be
seen as positive or negative depending on the person. Our perception of performing tasks is
influenced by motivation; if somebody was extremely motivated to do something they might see the
job as relatively easy. A person who maybe finds it hard to get of bed in the morning might see a task
as difficult. Our emotions have a major influence on how we perceive things. If we come across a
person from our past and the last encounter was negative then when we meet again the emotion will
tend to be cast in a negative light. First impressions and indeed last impressions also affect how we
perceive our world. “A great deal of what is perceived is, in actuality, inferred. Instead of using data
from our social world to modify and improve our everyday theories of social life, we only seek or
remember that which supports our world views as we often go through life on automatic”. (Trinity
University)
Magic is one of the longest running forms of performance art and illusions tend to play a role in the
magicians performance. Visual illusions occur when the perception of a stimulus don’t actually align
to the physical reality of the stimulus. “Visual illusions occur because neural circuits in the brain
amplify, suppress, converge and diverge visual information in a fashion that ultimately leaves the
observer with a subjective perception that is different from the reality”. (Nature Reviews 2008)
If we take spoon bending for example and try to explain the illusion. The magician takes the spoon
and starts to shake it up and down and the neck of the spoon looks soft and bendable. This is because
of the dancing bar illusion which affects neurons in our brains which respond to motion and the
termination of edges. These end-stopped neurons as they are called are different to non-end neurons
and the response between these causes a seemingly solid object to look flexible.
When a member of the public goes to see a magician he/she will naturally be suspicious of the
magician. This can work in the magicians favour as when a trick is being performed the member of
the public will try to go over the trick in their mind to try and solve it and this is where the magician

5. can influence the person by using memory illusions or misdirection. Implied information and
unspoken assumptions used by the magician are used to influence the participant when they are
reconstructing the trick in their mind. This effect tricks the participant into believing what he was
directed to believe as opposed to reality.
Our eyes are connected to the brain by the optic nerve which transmits everything our eyes see to the
brain. The optic nerve is a bind of millions of wire like structures which carry electrical impulses
away from brain cells. This according to Macknik seems like a lot of capacity which he compares to
an iPhone that has an 8- megapixel camera but can still take bad pictures. But our world through our
eyes is enriched by the brain constantly making the world clearer. Macknik says that because we see
the world with limited resources we can only perceive a little amount of the information available.
Our brains firstly see the edges of objects and then try to determine the inside. “So the brain is taking
this kind of very sparse information about the world and it’s generating this rich world by filling in
information,” says Macknik. “Your brain is doing that with virtually everything you’ve ever seen.”
(Conde, Macknik. 2010)
It is when our brains begin to fill in the details that we can get it wrong and this is where magicians
fool us, and this will bring us onto illusions.
Some of the ways the human mind works are just phenomenal. Some optic illusions despite knowing
what they are and how they work, your mind just won’t let you see them without the illusion being
present. An example of this is “Crazy nuts”, where we see a guest on Ted talks who’s is showing us
an apparent 3D shape of two nuts from a hardware store. This is actually a flat piece of card combined
with shading and colours to make it look 3D. The nuts are positioned to look as if one is laying flat
and the other vertical on top of it. He puts a straw through the two holes of the nuts as if they were
side by side. On first viewing this it seems impossible and even after seeing how the trick works and
seeing a full view of the entire object it is still impossible to imagine how it works and this is why the
human mind is so easy to fool with illusions.
Chinese linking rings are a great example of how a magician can use motion to fool his audience into
believing in magic. This ancient magic trick involves the magician showing a number of metal rings
to the audience, even passing around certain rings for inspection. The magician then hits the rings
together in his hands and they appear to join together before your eyes. What we do not see is the link
or gap in the ring that the magician is usually covering with his hand. The very fast motions of this
trick make it difficult for the eye to perceive what is really happening. The magician is not using any
forms of misdirection as they usually do but more over stimulation. By moving the rings so fast and
repeating the motion we are less likely to see the crucial moment when the magician clicks the rings
together.
Simple slight of hand tricks are the basis for a lot of magic tricks. This is a movement performed and
perfected by a magician where the audience is fooled with a subtle flick of the wrist. “Palming” is a
popular technique where a magician will show you an object, lets say a red ball. Then the magician
moves his other hand over the ball and appears to pick it up. While we are looking at his clenched
hand the magician can slip the red ball back into his pocket. This trick is highly effective because it
plays on top down processing. We all are familiar with the motion of picking something up so when
we see the motion we expect to know where the ball has gone.
“The most familiar objects are dealt with, and are made to vanish and re-appear in unexpected places
as if they really were disembodied and reinstated” (Edwin, S. 2012)
Another example of how a magician can shape your experience of an act using perception and slight
of hand is the cut rope trick. In this simple trick the magician shows you a long length of rope. He
then pulls the rope through his hand to make a loop. Using a scissors the magician cuts the loop.
When he reveals the rope again it is still in one piece. This illusion is achieved by having a small
length of rope concealed in your palm. This is the rope that you cut, not the long length. The Gestalt

6. principle the law of good continuation is occurring here once again as our brains automatically
assume that the loop at one side of the magicians hand is connected to the rope at the other side and
we group them together.
The art of misdirection is of paramount importance to performing magic. Audiences are tricked into
believing that an impossible feat has been performed, while the attention of the observer is being
misdirected. This misdirection allows the magician to perform the seemingly impossible by
controlling our perception and attention to where he wants it. Our brains can only process a tiny
fraction of this information which is sent to it from our sensory organs. Magicians can exploit this,
two common methods for controlling our attention and diverting it through physical misdirection and
psychological misdirection. Our perception of the world is altered by numerous variables, from the
events and circumstances which happen to us from when our memory begins until the day it ends.
As a species we can be fooled extremely easily. We all carry around frames from which we interpret
the world around us. Our frames are specific to us individually, they are affected by how and where
we grow up, who's close to us and almost every interaction we were ever part of. These frames are
constantly changing and constantly change how we perceive the world around us. Each frame has
bias, prejudices and ingrained judgments.
Physical misdirection is a common tactic among magicians. “There are many ways a magician may
perform misdirection such as, pointing, wide gestures and focusing the audience's attention on
another source”(Dean, 2014). Physical misdirection is the cornerstone for all magic. "Physical
misdirection is the foundation on which all magic - tricks, illusions, escapes, pick pocketing, mind
reading, and even physical comedy – is based”. (Mind and Magic: Manipulating Perception through
Physical Misdirection, 2014).
"Psychological misdirection is much more subtle however – a good example is the false solution".
(Dean, 2014) An example of psychological misdirection is cold reading. Cold reading is used among
self proclaimed psychics to trick an individual into believing that they can predict their future or
possibly to make contact with a deceased family member or friend. The key to success in deceiving
the individual is in linguistic skill. The Barnum effect is utilized "The Barnum is effect given a name
to a subjective validation in which a person finds personal meaning in a statement that could apply to
many people" (Barnum effect - The Skeptic's Dictionary - Skepdic.com, 2014). A typical example of
the Barnum effect is stating, you are really an extrovert but sometimes you find yourself being more
introverted, or vice a versa. This type of statement can apply to the large majority of the population.
Once an individual starts validating statements made to them their perception can grow more positive
or trusting towards the readers. With an understanding of body language, linguistics tricks and skills
the cold readers can be very perceptive into making themselves believable.
Our perception of people has a massive role in deciding whether we should trust them or believe
them. Each and every person has a certain frame of how they view and interact with the world around.
Our individual frames are affected by many things, how and where we grew up, the people who were
close to us and almost everything our senses pick up is changing our frame of the world. We see the
world through tinted glasses, some people may see the ultimate beauty in a Van Gough painting or be
utterly obedient to the words of a minister, and our perception of the world is not 100% equal. We see
through our frames. Our frame effects our perception - we carry around bias, prejudges and judgments
with us.

7. Remember, the next time you see a magician, that he is tricking your brain and not your eye. You are
actually fooling yourself. The more you try to solve his mysteries by using your intelligence, the more
easily he will baffle you.
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achs, E. T. 1980. ‘Sleight of hand’. New York: Dover Publications.
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