Stonebound-2011

Stonebound 2011

Essays from Genii Magazine 2011

Writing on advanced
misdirection

Cognitive Conjuring

Change Blindness! This wonderful phrase that cognitive science ”Change Blindness”, and track down the findings by McConkie,
has contributed to the area of pop-science. We all know what the Currie, Rensink, O’Regan, Clarke, Grimes and others. Make sure
phrase entails, and have known for a long time - card under glass, to visit www.viscoglab.com and nivea.psycho.univ-paris5.fr
body-double techniques in grand illusions, Tommy Wonder’s Cups
& Balls loads etc. etc... But until the phrase ”change blindness” was 1
coined, we never had a word for it.
However, it is easy to become a subject of self-aggrandizement
when we see how the cognitive science borrow ideas, without
proper crediting, from our art. But it would be a mistake to think
”this is all old ideas to us” and ignore the findings this science has
made, because there has been plenty of important new discoveries
as well. A small number of these findings has permeated into our
art, unfortunately with lousy crediting on our part as well, but the
area is huge and we have not even scratched its surface yet.

Remembering the present Change Blindness 2
A recurring scene in many bad movies and TV series is when
someone is hypnotized in order to remember something that is Take a look at Figure 1. To the left is a stock photo of Stonehenge
essential to the plot, with the claim that the eye works like a camera and to the right is the same photo where I’ve photoshopped out
which observes everything and that the mind subconsciously a large lintel (horizontal capstone). If I were to switch quickly
stores everything we see. Fortunately (for us), it doesn’t work like between those two photos, as in a flick book, the difference
that. Instead, it is only certain key elements that are remembered, would appear as a movement in the image, and you would spot
and then the mind extrapolates the rest. And when we return to the change almost instantly. Our eyes are good at spotting single
a visual scene, the things we then observe is superimposed and movements. However, if we introduce an intrusive distraction for
edited into our recall of the scene. That is, in certain situations, a split second, just as we switch between the photos - let’s say
even if something has changed, we remember it like it has always a bunch of annoying squares that suddenly appear, like mud-
been like that. Or in other words, a lot of the things we believe to splashes on a windshield window, as in Figure 2. Then, as we are
be memorized information, are really dependent on external visual almost defenseless against such visual intrusions, our eyes will
stimuli. jump to the distractions and during that saccade (the term for the
Here, I recommend that you track down my June 2009 column ”In fast movement of the eyes from one point of interest to another),
the Gaps, Magicians Reside”. Also, you should be aware that my
description of this phenomena is shallow and over-simplified, and
maybe even severely flawed, since a lot of the theories are quite
over my head. Therefore, I suggest that you google the phrase

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we are practically blind and can not observe the main change in the A few years ago, a team led by Melissa R. Beck found that it
photos when it occurs. And it is at this point it gets really interesting. is much easier to spot a probable change than an improbable
Even if we have looked straight at the stone in the photo before the change - which is somewhat contrarily to what common sense
”mud-splash”, and believe that we have memorized the situation would indicate. One would think that we would miss ordinary and
- when we return to that spot in the photo and see that the stone mundane changes, but notice strange and irregular changes - but it
has vanished, the memory is instantly revised so that we believe seems to be quite the opposite.
that the scene has always been like that; no lintel. During the next For example, compare Figure 3 and 4. Since it is very probable
mudsplash, we will miss that the lintel appears again, and the mind that a door can be open or closed, many people will spot the
is once again revised so that we remember that the lintel has been change, even with distracting mudsplashes. But most people would
there the whole time. miss an improbable change, like in the change between Figure 3
What makes this phenomena tricky to exploit is that all changes and 5 where a window has moved along the wall. Yes, I know, it is
are not equal. For example, if the change is that a girl’s sweater still tricky to figure out how to make use of this - especially when
changes color, then we would probably not notice it. But if the considering that most of our effects consist of improbable and
change would be that the girl’s appearance switch between being very noticeable changes. The trick to make this work, I believe, is
dressed and being nude, then I don’t think there would be enough to create improbable changes that are outside the plot and out of
mud-splashes in the world to cause male heterosexuals to miss it. focus. Let’s try to make use of this in a card trick.
That’s just a guess though.

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Cognitive Color Change 6
I created this trick to see if it was possible to begin by showing a 7
blue-backed deck, then cause the audience to forget that the deck
is blue, so that they will be surprised at the end when the deck is 8
shown to be blue. And yes, it is possible.
To prepare, put a red-backed card at the bottom of the blue-backed
deck. Then put a face-up red-backed Joker in the center of the
deck. Put the deck into the blue case, so that the face of the deck is
towards the half-moon cutout in the case.
Now, the case has to be prepared as well. Take a red card case,
and cut away the front and one of the long sides, then slip the
remainder over the blue case (Figure 6) and glue it in place. You
now have a case that is red on three sides and blue on three sides.
To perform, bring out the cased deck, taking care to only show
blue sides toward the audience. Open the case and take out the
deck, and make sure that you briefly look at it yourself (Figure 7),
á la Ramsay’s ”if you want someone to look at something, look at
it yourself”. My theory here is that it is more easy to remember that
the case and the deck has the same color, than to remember what
the particular color actually is. So far, I haven’t been able to discern
whether this theory is right, wrong or irrelevant - but for now, let’s
assume the theory is valid.
Place the case on the table, blue sides towards the audience. Hold
the deck from above in a right hand end grip. Move the left hand
underneath, as to square the deck, but the left fingers push the
bottom card to a slightly right-jogged position.
Say: -”One of these cards are different from the others. Can you
guess which one?” and spread the deck face-down from left to
right (Figure 8). My theory here is that if I provide the single face-
up Joker as a point of interest, it will lessen the risk that anyone
accidentally consider the color of the backs to be a point of interest.
When the spectator point out the Joker, push it out of the spread
and gather the rest of the deck, taking care not to expose the
redbacked card at the bottom.
As you say: -”But the Joker is not the only card that is different”,
you turn the deck over and spread it face-up, while the left hand

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simultaneously turn over the card case so that only red sides are return to the case, their memory will be revised so that they believe
towards the audience (Figure 9 to 11). The movement of the right that the case has always been red.
hand should begin from a position near you, and move forward. If you at this point would exclaim ”The whole deck has turned blue!”
The movement of the left hand, as the case is turned over, should and begin to turn the cards face down, I estimate that only about
retract away from the audience. This is based on Slydini’s ideas 10-25% of the audience would perceive it as a magic effect and
of coordinated actions, and will have the same role as the mud- become surprised. Therefore, we need to strengthen the situation.
splashes mentioned earlier. If you look at Figure 10 and 11, you In my June 2009 column, I also talked about patterns and that
will notice that the red sides of the case comes into view, just as if we had three examples of something, it becomes seductively
all the blue backs goes out of view. This sudden and improbable tempting for our brains to assume that those three examples are
change of the case’s color is masked out by the forward movement a representative pattern for a larger set. Here, we have just one
of the right hand in Figure 10. And now, when the audiences’ gaze

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reference point that indicate that the deck, presumably, is red- from the right end of the spread, and use it to scoop up the spread
backed; the case. Let’s add some more reference points. (Figure 12). Square the deck and place it face down right in front
The deck has just been turned face up and spread. Continue: of the case and the Joker. We now have three points of reference,
-”There is another card here in the spread that also is somewhat and the pattern is firmly established. Now, we can let the effects
different...” Pick up the joker, and turn it face down as you move it play out.
backwards. Casually point with the red-backed Joker towards the Tell the spectator: -”Great! Keep your finger onto the card, and
spread card and say: -”... and I know that you will find it. Just put say ‘change’!” When the spectator has done as asked, you say:
your finger onto the card you believe to be different!” Then, place -”Amazing! The card have changed color to blue!” and turn the card
the Joker face down next to the card case, which gives us two face down (Figure 13). Wait a few seconds for this to sink in, then
reference points that indicate that the whole deck is red. conclude: -”Of course, I just messed with you. All the cards work
The spectator puts a finger onto a card, let’s say 4 of Spades. Push like that. Change!” On the last word, you slap the face-down card
it out of the spread, then take the face card (which is red backed) onto the deck, and immediately spread them, making sure to keep
the top two cards together (Fig 14 and 15), which is an impressive
color change.

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As we set out to do, we have now showed a blue-backed deck further instructions or rules. It was an artistic experiment to see how
to be blue, and have caused the audience to perceive that to be people would classify themselves - and sure enough, the majority
an impressive magic effect. While this might seem like a great started to line up, queuing at the door for “Ordinary people”,
application of change blindness, remember that even this is just while looking with envy at the small minority who just glided past
a scratch on the surface of a huge field. There are a lot of more without queuing at the door for “Important people”. The latter group
applications that has not been discovered yet. This is fertile virgin consisted not only of the ones you’d expect, but also included a
grounds for experiments and development. very small number of “rebels”, individuals from about all social
classes, who had begun queuing among the “Ordinary people” but
Will the color-changing effect I described always work? The short soon decided that “Damned it, I’m important too!” and switched line,
answer is no. My experience with this effect has shown me that it while receiving dark glances from the majority who remained.
doesn’t always work if the observer is a card expert who find it a This should be fuel for some serious pondering. What kind of
point of interest to check out the brand of cards that the performer mechanism causes a majority of people, when they have a free
is using. The success rate is also lower, if the observer is a choice, to decide that they are “ordinary” and not “important”? What
magician who perform, or have performed, any color-changing deck else do they stop themselves from? Or rather, since we, you and I,
routine. Hands-on experience seem to affect perception more than are people - what do we stop ourselves from?
theoretical knowledge. About 25% of magicians in general will not I’ve got a friend who claimed that he wasn’t creative, and by
fall for this effect. And so far, I have not failed once for laypeople. looking at his performances, you’d assume he was right. But then
I happened to hear him tell a bedtime story to his kids... And it
My friend Tomas Blomberg alerted me that my routine shares some was amazingly innovative. Seems he’d just decided that he lacked
similarities with Paul Harris’ ”Amnesia Switch” (Magic Magazine, the creative potential within all areas that mattered, but forgot his
September 2001). Thanks to Josh Jay, I recently got hold of that decision when it came to an “unimportant” task like putting the kids
description, and fortunately, there are also significant differences. to bed.
Feel free to study and compare the two. At times I’ve been asked to direct other magicians. Both those
considered “good” and those considered “lousy”. And the work has
You are brilliant! been the same, because in both cases there have been original
thoughts hidden behind a bunch of crap - invariably stuff that have
There are a lot of misconceptions about creativity and intelligence. been picked up from DVDs and from old obsolete traditions, things
Many people seem to think that they are esoteric traits that you are that just detract. So it has just been a matter of chopping away
either born with or not, but I know from experience that it is a craft the things that detract, and get the person to trust his own ideas.
that anyone can learn. Anyone has the potential for greatness, but Because they are always there - the great, personal and original
the sad thing is that many people are taught to believe otherwise by ideas. Sometimes they are just a faint glimmer behind a big wall of
the social environment. crap - but they are always there. Always! Creativity can never been
I remember a striking example of this, from the opening of an art eradicated, it can only be hidden or forgotten.
exposition here in Sweden in the 1990’s. They had made two doors So when we meet, you and I, at some convention in the future - I
for the entrance. On one door the entrance sign said “For important want you to show me something you’ve come up with. Because, let
people” and on the other it said “For ordinary people”, with no me assure you, that, even though I don’t know you, I know that you
will be brilliant!

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Slow and slower does the trick

Look at your watch (Figure 1). rate is around 60-90 slides per second, but if there is motion blur in
See how the seconds hand the photos you get the illusion of movement already at 15-18 slides
rush around the face. It’s per second. That is, if you look straight at the photos - the sides
speed is very noticeable. Keep of the eyes are more sensitive to flicker, which you can check out
your eyes glued to the watch, yourself next time you go to the cinema. During a bright scene, look
and let the seconds hand make up into the ceiling instead, and you’ll be surprised over the amount
five complete revolutions. Dur- of flicker from the screen that you, up to then, had missed.
ing those five revolutions, the ”Time resolution” is not quite a proper term to use in a discussion
minutes hand turned a whop- like this, since our eyes provide us with a continuous visual feed,
ping 30 degrees, and moved rather than serving us time-slices of information - still, it can be an
from one digit to the following useful analogy. During certain conditions, the human eye perceives
digit. The distance it traversed rapidly changing images to be a continuous movement, already at
is considerable - on a wall 20-30 images per second. A house fly, for example, have a higher
clock, the distance the minutes time resolution than humans - flies would still only see a rapid se-
hand moves during five minutes can very well be three inches. Isn’t quence of still images, where we would see continuous motion. I
it pretty strange that, even though you stared at the watch, you guess that is why flies never got hooked by ”Lost”.
never saw the minutes hand move?

My father, the farmer, had an uncanny knack of being able to As you might remember, last time, in March, I talked about change
catch house flies with his finger tips. With a steady movement, he blindness and how to apply it in a magic trick. This time, I’m going
very slowly reached out and picked up the fly when it was strolling to venture out onto a less solid firmament. The underlying theory
around. Knowing how fast a fly can be, his movement were incon- and science is solid, but the theories on how to apply it will be
gruously slow, yet he caught the fly more often than not. I’ve got highly theoretical since I lack empirical data to support any of it. But
no idea how he did it. His explanation was that a quick movement long-time readers of Genii will fortunately be no strangers to pipe-
seldom worked; the fly away instantly. So he decided to try the op- dreams and wishful thinking.
posite approach. Tried to find a speed that would cause the fly to Most people, when talking about time resolution, are focusing on
misjudge the potential danger until it was too late. Apparently, there the upper range; the point where motionless images suddenly gives
is a such speed. the illusion of movement. On the other hand, the lower range has
Let’s say you are watching a slide show of photos taken in se- hardly been explored at all, and that area is equally fascinating. I
quence, and you begin to increase the pace of the slides. At a cer- mean the point where we perceive something to be static and mo-
tain rate, it will cease to look like separate still images, and begin to tionless, even though it actually is moving. As in the watch example
look as a continuous motion. If the photos are sharp, the required at the beginning of this column - where we knew that the minutes

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hand were moving, and yet were incapable to see it. Or with my every viewer will notice that the car changes color from blue to red.
father’s curious knack - if the upper boundary of a house fly’s time The increment per second is too large. But if the duration is in-
resolution is higher than ours, then maybe it’s conceivable that the creased to 30-40 seconds, very few will notice that the car changes
lower end is higher as well? Humans perceive the minutes hand color, even when they are looking right at it. As with regular change
on a watch to be motionless, and maybe the seconds hand appear blindness (see March issue), it works best if the change is slightly
motionless to a fly? And maybe my father had found the perfect ra- outside the center of attention, and if it is an unpredictable change.
tio between time resolution and increment of position, for the fly to (Also, see the links at the end). Interesting, right? But how does
perceive the approaching fingers of doom to be motionless? one apply such an abstract idea on a magic piece?
Yes, I am well aware that this is pretty weird stuff to think about, let The first idea I got was interesting, but patently unpractical. The
alone to write about. But sometimes it is necessary to venture out idea was to mess with the set design. To begin with a normal-look-
into uncharted territory to find new riches, and I believe that is what ing stage (Figure 4), and then gradually during half an hours show
we have here. First, let us delve into what is known. cause the perspective and proportions of the set to go all weird and
Let’s imagine that you make a video cross-fade between the pho- strange (Figure 5) - with the intention that no one would notice that
tos in Figure 2 and 3. If the duration of the cross-fade is 5 seconds, the set actually changes, and hopefully cause the audience to get
a vague feeling that their grasp of the reality is slipping.

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Just to be clear - I am discussing theory and unexplored areas So, I thought, maybe a slow change would be a solution? That is,
here, and to make it less abstract, I am illustrating it with my own firmly establish that a frame is open and empty, then put it slightly
unfinished work, because there exists no other work to refer to. The outside the center of attention, where the opening is very slowly
examples here are not up for grabs (you are welcome to ask for closed up right in front of everyone, and then the Flash Appearance
permission, though). is performed. Or perhaps as in Figure 6? You have a slim and open
The next idea came about when I was pondering the fact that I’ve cabinet, like a wardrobe, where the inside back wall is the frame
never ever seen a convincing Flash Appearance illusion. Can it with the roller-blinds (noted A in the illustration). Behind this frame,
even be done convincingly? There seems to be two versions of it a person is hidden (B: the outside back is just stretch material).
- the first is usually performed in complete darkness, and then the As soon as it has been firmly established that the cabinet is empty,
audience is blinded with a flash pot, and half a minute later when the roller-blind frame slides forward at a slow constant pace, until it
the eye-sight returns, you find that the performer have entered reaches the front. Now, the blinds can be released, whereupon the
the stage and started the show. In the other version, the audience cabinet looks like it did from the start again.
see a frame that is closed up with a black curtain. Then the curtain The simplest way to establish that something is empty, is to have
is pulled away, and the performer that was hidden behind steps something in it and then empty it out. So, let’s say that you have
through. For some reason, this is usually performed in front of a red two folding chairs and a folding table (and more) in the cabinet to
or blue backdrop. begin with (Figure 7). You take them out and while you arrange the

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chairs and the table, magically producing coffee and biscuits etc., I’m quite sure that the principles and theories will work - the only
the roller-blind frame takes a 90 second journey from the back of tricky part is to figure out exactly how slow a change should be.
the cabinet to the front (Figure 8 - 10). Then you turn around and In the piece above, the slow change can probably be done rather
magically produce a guest from the cabinet - and after the produc- quickly (90-100 seconds), since it works in combination with black
tion, the cabinet looks just as it did at the start again. art in a trick cabinet. But each new piece is likely to require different
(The interior is dark gray in the illustrations, to show what is hap- time lengths to be deceptive. Best way is to do computer anima-
pening - but it should be black). tions and try out various time lengths.

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The next idea is derived from a piece by Tyler Wilson (plot used by the performer says that this is a good analogy for magic, as a white
Tyler’s kind permission), which I’m currently experimenting with, for sheet is picked up from a stand on a small table nearby, and is held
my own use. The idea is to use a slow change, to openly but covert- behind the cut-out (Figure 12) -”And look, suddenly you can see a
ly exchange one item for another. white vase instead of the faces - but the faces are still here. The
The audience is show a black plastic sheet, with a cut-out of the two are the same thing, vase and faces, at the same time! As in
optical illusion known as ”Rubin’s Vase”, but it is handled to only magic - a red silk can be a white egg, and vice versa. Keep this in
focus on the two faces - make them talk or kiss (Figure 11). Then mind!”

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Put the white sheet and the black cut-out back in the stand on the
table at the side (Figure 13). Now, go into any three-minute routine,
and during that time, the stand on the table slowly rotate 180 de-
grees, and the cut-out is replaced with a real vase (Figure 14-18).
The switch happens out in the open, but it will still not be noticed -
so it will be a huge surprise, when the routine ends with the produc-
tion of a flower, that is put into a real vase that just a moment ago
was a 2D cut-out.
The same idea could be used for other kinds of switches. Let’s
say the audience checks two empty tubes that will be used later -
and they are slowly switched for two tubes loaded with Multiplying
Bottles. My estimation is that it requires 3 minutes for a 180 degree
turn to go unnoticed - maybe a tad shorter or a tad longer.

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The Dunning-Kruger Effect
(for fun and profit)

According to Wikipedia, this wonderful source of facts and
disinformation, the Dunning–Kruger effect is a cognitive bias in
which “people reach erroneous conclusions and make unfortunate
choices but their incompetence robs them of the metacognitive
ability to realize it.” The unskilled therefore suffer from illusory
superiority, rating their own ability as above average, much higher
than in actuality; by contrast, the highly skilled underrate their
abilities, suffering from illusory inferiority. This leads to a perverse
result where less competent people will rate their own ability higher
than more competent people.

19 Isn’t that wonderful? There has actually been made a scientific
study on the old knowledge that nothing bolsters confidence as
I could go on and on... You take 4 billiard balls from a Thayer Ball much as total incompetence. And I’m quite happy that it works like
Stand (figure 19) and make a trick with them - suddenly they all dis- that, otherwise I would never have accomplished anything in my
appear, and when you look at the stand, you find that all the balls life.
have returned home. There’s plenty more that can be done. Feel For example, in 1999 I made a computer animation, using the
free to discuss this at the forum at www.geniimagazine.com . POV-Ray software, that had some birds flying in the background,
For more on slow gradual changes, take a peek at these links: but was dissatisfied since the birds flied in strict formation like they
http://nivea.psycho.univ-paris5.fr/Slowchanges/index.html were tied to an invisible railroad track. So, despite not knowing
viscog.psych.northwestern.edu/publications/Simons_etal_gradual. anything about computer programming, I decided to write a piece
pdf of software myself, that would generate a more natural looking
flock of birds, thinking; -”There are 15-year olds out there who are
writing advanced computer viruses, so how difficult can it be to
write a small thing like this? I can probably do it over the weekend.”
Well, it took me close to three years to write it, and besides learning
programming, I also had to study slow-motion footage of birds to
figure out how they actually move their wings, taught myself a bit
about artificial intelligence so the virtual birds could make decisions,
learnt ray-tracing algorithms to give each bird some limited eye-
sight and figured out how to use four-dimensional quaternions to
make the birds bank along the flight without ending up in a gimbal
lock... I finally made it work, and it works well, despite that it is

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Magic, as I think of it, is not theater. It is related, like a cousin to
theater, but it is an art and a craft on its own merits. I think of the
relationship as in the diagram here (Figure 1). Magic and theater
as two separate circles, with a small overlap - the theater sometime
use magic techniques to enhance a drama, and magicians can use
theater techniques to enhance our deceptions. But expertise within
one circle does not bestow anyone with automatic competence
within the other circle. And I have found that, at least for my own
purposes, that the most important things I’ve drawn from the
overlap does not come from acting, but from playwriting, theater
direction, stagecraft and from the Keith Johnstone style of theater
improvisation, which is a hybrid between acting and real-time
1 playwriting (i.e. the theater’s version of “The Trick that can not be
Explained” ).

written with horrible spaghetti code - but at the same time, I’ve What is good about the Dunning-Kruger effect is that it can,
learnt about how utterly incompetent I was for the task. Today, after with practice, be called upon at will. For example, when Richard
learning how difficult it is, I would never attempt it at all. Kaufman asked me to write a bi-monthly column for Genii, I
When I was younger, I was quite fond of the Robert-Houdin quote knew that it was impossible, because my past experiences as a
“a conjurer is an actor playing the part of a magician”. It seemed magazine editor have taught me that I can’t handle deadlines,
very reasonable to me... I thought, “acting... how hard can it be, since they give me a writer’s block. But since I enjoy to give myself
really?” Then I joined an amateur theater group and discovered challenges, I was able to make myself ignorant of my shortcomings,
that not only is acting very different from magic, it’s also bloody to the degree that I could say. -”Yes, of course, I can write a bi-
damn difficult as well. I might be a good magician, but I know monthly column. How hard can it be?”
from experience that I can’t act myself out of a wet paper bag. I’m You can try to do the same. Give yourself a task that you know is
now also pretty convinced that the ones most fond of the quote, beyond you, then just ignore the obstacles and keep on saying
simultaneously are the ones that knows the least about acting. And “How hard can it be, really?”, and you will surprise yourself on what
that would be perfectly all right, if they took action on the quote and you can accomplish if you are stubborn enough.
actually tried to apply some acting techniques on their magic - but
for some reason that seldom happens. Myself, I’ve learnt enough
about acting to know to be careful to profess competence within
that craft.

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Wonders of a fragmented vision

The thing we call “Change blindness” these days isn’t a very should anyone notice it - so what? It has no relevance at this point,
new thing for us magicians. There has been plenty of effects that and will be quickly forgotten.
makes use of the phenomena. But what’s new is that we, thanks to Let a spectator choose and sign a card. Tell the spectator to show
cognitive sciences, now have a more exact knowledge about how it around. Lean forward and indicate someone -”Show it to her as
and when it works. And we also have access to a better language well!” and at that exact point, calmly steal away the ”spare” card.
to express ideas of that nature. However, we are still just scratching Easiest is to to lower the deck on top of it, and then pick the card
on the surface when it comes to how we might apply this new up underneath the deck.
knowledge in our performances. That goes for me as well. I might Take the card back from the spectator and show it around a
sound confident in this column, but I’m struggling with the concepts bit more. Then make a top change and place the switched-in
just as much as anyone else. indifferent card face down on the table. Palm the top card of the
So, let’s explore the potential possibilities together. I guess that the deck (the selection). Now, load the card underneath the glass in the
simplest way of getting the hang of it, is to take tricks where change standard manner, as the other hand make a table spread with the
blindness already is a factor, and see if we can take it a little bit deck: -”You could have chosen any of these...”
further. Everything is now set up for the ending. Vanish the card that the
Heba Haba Al’s “Card under Glass” and variants are excellent spectators believe is the selection, in an as clean and strong
examples on where change blindness is a factor. We know that manner as possible. The Rub-a-dub-dub vanish (Expert Card
is is possible to load the card under the glass and leave it there in Technique, Hugard & Braue, 1944) might work but I think it might
plain sight, over and over again, without getting caught. If you go be a tad too weak (see ”Too Perfect - Imperfect” in the October
back to the Genii issues June 2009 and March 2011, you’ll see that issue of Genii 2001). A card flap box might be better, or a black art
it is those mechanisms that are in work in ”Card under Glass”. So, vanish against a black close-up pad, or a lapping vanish... anyway,
just as an experiment, let’s see if we can fuse that trick with Bro. the card vanishes completely. End the mash-up by saying: -”Oh,
John Hamman’s ”The Signed Card”. it vanished! And with your signature, it was the only one of its kind
Place a card openly underneath a glass on the table. Refer to it as in the whole world. What a pity! I wish we had a spare...” Wait until
a spare, in case you loose a card later on. This card will later be the audience makes the connections, then let the spectator lift the
stolen, so it’s good if the card has a bridge in it, or is shimmed or glass and turn over the card.
something. Yes, it is on purpose that I’m vague on the details above. If you
At some point later on, arrange a situation where you have to reach want to find out the possibilities and limitations of making use of
forward with one hand - simultaneously, with the other hand, nudge change blindness, you really have to think a lot on where and when
the glass off the ”spare” card. There’s no heat at that point, and to make the moves, and find out by yourself. Serving the exact
details on a platter will only result in limiting the techniques to this
specific trick, when it can be used more universally.

16

12

More examples? Another routine where change blindness already is the load is off to the side, the less reason they will have to keep track
a factor is Tommy Wonder’s famous Cups and Balls routine (p. 105, of it later. Instead of actually looking straight at the load, they will look
The Books of Wonder vol 2, Tommy Wonder & Stephen Minch, 1996). at other places and just fill in the image of the load from memory. To
In that routine, the final loads are in plain sight on the table, already accomplish this, we make use of John Ramsay’s adage ”If you want
from the start - yet, no one notice it when the loads are grabbed someone to look at something, look at it yourself...” So, right after
and shoved into the cups, it isn’t even noticed that the final loads placing the load to the side, after its sudden appearance, look up at
suddenly are missing from the table. Let’s attempt taking that a small the audience as if you are going to say something, but stop and look
step further. For this example, let’s assume that the final loads are at the load again, as if you are still wondering where the wretched
hidden in a servante behind the table. Right at the start, load one of thing came from. Repeat that two times more (Figure 1) - that will be
the loads into one of the cups, using a standard Cups and Balls load. enough to firmly establish the image in the minds of all the spectators.
It is possible to make a whole phase of a routine without revealing Then just ignore it and continue with the routine. A while later, you
the load, by blocking it from falling out with a little finger. After the first have one cup in each hand. The third cup has secretly been loaded
phase, lift the loaded cup and reveal the load. Act surprised yourself, with a small ball, and another small ball is on the table next to the
as if this was something unexpected. Move the load off to your left cup. Reach over, diagonally, with the left hand and point at the visible
side. Now, you want to really stress and establish this image firmly in small ball. The mouth of the cup in the left hand should be aimed
the minds of the audience. Because, the more certain they are that straight at the load on the left side (Figure 2). As it is done, you say

17

3
4

5

something like -”Keep an eye on this ball...” same distance from the inner table edge. The right hand picks up
Immediately, drag the left hand back towards the load the visible small ball (Figure 4-5).
simultaneously as the right hand moves forward to indicate the third So far, we are still following the ideas expressed in Tommy
cup: -”...and this cup”. The movements of both hands should start Wonder’s routine. The load has been stolen from the table, into a
and stop at the same time (as expressed by Slydini), and the mouth cup, and no one has noticed that the load is missing. We all know
of the left-hand cup should end up covering the load on the table. that this works in practice, so there should be no doubts this far.
The left little finger assist in getting the load into the cup (Figure 3). But let us now add a new idea. The load is gone from the table, but
Move the cups in both hands over to the right side of the table. no one knows it yet. The spectators are still filling in the existence
When doing this, make sure that the movement of the left hand of the load from memory. So, what if we secretly place another
doesn’t get a forward vector, but is moved along maintaining the identical load on the spot where the first load was located? Then

18

6
7

8

we would get yet another step further ahead of the audience... (check your old physics books from school). So let’s try it.
...You have the visible small ball in your right hand. Make a false Your left hand has just grabbed a load in the servante, and the right
transfer to the left hand and let the ball vanish. As the right hand hand has taken hold of the third cup (Figure 6). Now, both hands
moves forward to grab the third cup, the left hand drops down into will move in unison, and the movements will start and stop at the
the servante and grabs a load (Figure 6). Now comes a slightly same time. The right hand lift the third cup upwards, a tad higher
tricky bit. than usual. At the same time, the left hand with its load is raised up
According to Slydini’s theories, one movement can be cancelled from the servante and onto the table where the first load used to be
out by doing another movement. Most examples deal with (Figure 7).
canceling out movements downwards or away from the spectators, This is a sensitive moment. The slightest movement with the left
by using movements upwards or towards the spectators - as the hand might tell the audience that something has happened. To
latter are prioritized in our primal reflexes. But to lift a load up from avoid that, ”lock” the positions of the left hand and arm with the
the servante is a movement along the up-vector, so how do we muscles, then shift our body weight over towards the right, so that
cancel out that? My theory is that a movement like that can be the whole body and the left arm moves in unison. This is done
cancelled out with another movement along the up-vector, provided as the right hand swivel the mouth of the cup over towards the
that the second movement has higher kinetic and potential energy audience, to show the inside of the cup empty (Figure 8). Now, as

19

the left hand is away from the second load, you can relax and move for their level of thinking myself. I, myself, started out stupid, but
as usual again. with the realization that anyone could be a tad smarter tomorrow
So, what has happened? One cup has been loaded with a final than yesterday, and that has been my path ever since. Small steps!
load, without the hands getting out of sight, and everything looks Never giving up! My only real talent is stubbornness.
like it should. You can throw a quick glance towards the load on However, there’s nothing wrong in sharing good advise, as long
the left side on the table, to reinforce the mental image - and then as it is received as just that - good advice - and not as big sacred
repeat with a variant of the same loading sequence again. If anyone truths. And one piece of advice is the slogan I referred to earlier:
would mask out everything but the area where the visible loads are “No presentation is also a presentation”.
on the table, they would see something similar to the Stonehenge You should be aware that the spectators see more than you think,
example in the March 2011 issue of Genii - a load that blinks in and and that everything eventually turns into a story - therefore, it can
out of view repeatably, without anyone else noticing it. be useful to know and understand the mechanics of a story. The
natural assumption is that your performance begin when you start
No Script is also a Script the first trick, but the story usually begins much earlier. The item
you might refer to as “my funny presentation for Cards Across”
Something I early learnt from Max Milton, one of my first role might become the story of:
models in magic, was that everything is a part of the performance. -”I was at a restaurant with my wife last week, where we
This was not some sage wisdom he imparted to me verbally experienced a most curious thing. There was a guy standing in the
- rather, it was something that dawned on me when I tried to corner. At first, I thought it was a new waiter, because he looked
understand and emulate the way Max approached different at every table with a kind of nervous expression. But then, after
performance related problems. Through the years, I’ve eventually we had ordered, he suddenly looked our way and started to walk
distilled this down to a few simple slogans that I tend to hit my towards us, and I thought ‘uh-uh, what have we’ve done now?’
acolytes over the head with. At times, I’m approached by other Then he seemed to switch personality, smiled, and began doing the
magicians who are seeking advice for a piece, and in many most incredible card tricks I’ve ever seen. I tell you, the tricks was
cases, it is prefaced with the comment: -”I’ve got no presentation so amazing that I almost didn’t notice how he kept staring at my
for this yet.”, to which I immediately reply: -”That’s an intriguing wife’s chest. I guess I should have become angry over it, but there
presentation! Please go on!” The response to that is usually a blank was something non-threatening about it - like he was watching
expression of incomprehension, so I don my best guru-like visage science-fiction or something. Then suddenly, he stopped and said,
and say: -”No presentation is also a presentation!” very politely; ‘thank you for your kind attention’, and went back to
his corner and looked nervous again. I still don’t know what to think
I know, it’s not a nice thing to do, but I consider it to be self- of it. Weird huh?”
defense. Considering the vast amount of time I’ve spent I could go on and on about this, as I’ve done in the past and will
deconstructing and questioning the authorities within our craft, do in the future, but for now, I’ll just remind you that everything is
it is pretty cruel of others to try to make me into one. I’m not an a part of the performance, from the first second the spectators see
authority on anything. And while I don’t want to be ignored, I do you until the last second you are in view. Everything is a part of the
want to be questioned and refuted. I want you to trust your own story. No script is also a script.
mind, because that’s what I do. Had I ever believed that the giants
in our field were geniuses, I would certainly never dared to aspire

20

Vision & Velocity Vectors

You might want to hang on to something, because since this is exceedingly 1
difficult to write about, I assume it will be equally difficult to read. Don’t say that
I didn’t warn you! 2
Earlier this year I came across the work of Stephen Macknik and Susana Martinez-
Conde through a television episode of Nova ScienceNOW titled “Magic and the my hands-on field tests are in complete opposition to their hypothesis. What I
Brain” (which I watched as I wrongly assumed it would be related to “Pinky and the find is that, inexplicably, 2A draws a lot more attention than 2B. Not only that,
Brain” from the cartoon Animaniacs). I then found their article of the same name in since the straight path in 2A is a somewhat unnatural motion for the hand, it is
the December 2008 issue of Scientific American. In both instances I came across easily remembered by the spectator afterward. What is going on? Despite their
intriguing information that was in opposition to my own observations from real- immensely complicated descriptions about pursuit and saccadic control systems
life performances. Now, I fully admit that I am far from being a neuroscientist, in the brain, suppressed vision, neural activity, and whatnot that the authors have
but I pride myself on knowing a thing or two about misdirection (which, of course, published during the last three years—it turns out that it takes less than a minute
can be a case of self-deception—an area in which I also have considerable expertise).
Since Macknik and Martinez-Conde have also written a book on the same theme,
Sleights of Mind (2010), it is fair to say that their theories have received wide-
spread distribution. If these theories are flawed, or wrong, I feel that it is important
to refute them, and that is what I will attempt here. In particular, I will focus on
the hypothesis of “curved hand motions.”
In their work, Macknik and Martinez-Conde, together with their research
collaborator Apollo Robbins, bring forth the hypothesis that a hand that moves
along a curved trajectory will attract significantly more attention than if a hand
that moves along a straight path. Well, that sounds simple enough so let’s try it
and see.
In figure 1 we have two examples of hand motion along curved trajectories. Both
examples are natural movements of the kind with which we have experience in
magic. According to the hypothesis, as I understand it, both example 1A and
1B should attract an equal amount of attention. But, as it turns out, my own
observations do not fully agree with the hypothesis—example 1A seems to draw
considerably more attention than example 1B. I might be wrong, so try it out
yourself and see whether the theory fully agrees with your own observations.
Let’s bring it up a notch with figure 2. In example 2A, the hand is moved along
a perfectly straight path, while the hand in 2B follows a curved trajectory.
According to Macknik and Martinez-Conde’s hypothesis, example 2B should
attract significantly more attention than example 2A. Yet, observations from

21

to conduct a primitive field test which strongly indicates that the hypothesis 45
is severely flawed. That’s not a good indicator for the scientific validity of the
hypothesis. Neither is it a good indicator for the artistic applicability of it. Extrapolating from what Slydini gave us, we get:
Actually, it is enough for me to form a hypothesis of my own: That Macknik A movement in +z direction (toward the spectator) will get more attention than a
and Martinez-Conde have not done any proper research, but have simply taken movement in -z direction (away from the spectator) as shown in figure 4.
subjective guesswork and dressed it up with neuroscience-sounding pop-language A movement in +y direction (upward) will get more attention than a movement
to falsely make it look like it has merit. And that, in turn, should be enough for in -y direction (downward) as shown in figure 5.
you to form the hypothesis that I get pretty pissed off by people who use shoddy
research within “my” area as a shortcut to fame. That probably isn’t a very scientific
attitude, but fortunately I am not a scientist. but an artist—I am supposed to be
vehemently passionate about this stuff, and I am.
The strongest indicator that something is flawed with the hypothesis of curved
motions is the omission of the name Slydini—whose work in this context is
extremely important. So let’s add some of Slydini’s thoughts here. And since
it seems to be the way to do it, I will also dress it up to make it sound more
“scientific.” I’ve recently started to think along the lines of a force-field analogy,
but that model is still incomplete so instead I will refer to vectors within a left-
handed coordinate system. What “left-handed” means is illustrated in figure 3.

67
3

Extend your left thumb, first, and second finger, all at a 90 degree angle to one However, a movement in +x direction (right) will get equal attention as a
another, and point the first finger straight at the supposed audience. The second movement in -x direction (left) (fig.6). When the movement stays on the same
finger is now pointing in the direction of the positive x-axis (to the right), the plane from the spectator’s point of view, it doesn’t seem to create any discernable
thumb is in the direction of the positive y-axis (straight up) and the first finger difference in attention between a leftward and a rightward movement, except—
is in the direction of the positive z-axis (forward). For easy reference, keep your and here I venture out into my own theories—when one movement (positive or
hand held like that for a while. negative) along the x-axis is at a higher z-plane (i.e., closer to the spectator) than
the other (fig.7). Then the former will get more attention. The same is true if the

22

two movements along the x-axis are at So why does this work? Well, inside our brains are neurons that flare up when we
the same z-plane, but one of them is at a see certain things. The same thing is true of animals—there have been experiments
higher y-plane (fig.8)—one movement where they have hooked up a speaker to a cat’s brain, then shown the cat different
occurs higher than the other. things. For example, nothing happens when the cat is shown a line, but when the
The same seems to be true for two cat is shown a line which ends abruptly, a barrage of signals is heard in the speaker.
positive y-vectors; if one of them is Obviously, the end of a line is important to a cat’s brain. And that it affects the
at a higher z-plane, it will get more cat’s behavior is easy to see. They are interested in corners of furniture, where lines
attention. Likewise, if the positive meet and end. Keep a stick aligned with the x-axis and hold it out for the cat,
y-vectors are at the same z-plane, but trying to get him to sniff the middle of the stick—but the cat will always ignore
one of them begins and ends at higher the middle and go instantly to one of the ends (there’s bound to be a force in this).
y-planes than the other. An example If you point at something, the cat will only look at the end of your finger, not at
8 of this can be found in my July 2011 the item you’re pointing to.
installment of “Lodestones.” Our neurons also flare up based on various visual stimuli, but judged by our
Surprisingly, the +y vector (moving higher) seems to be a tad more important behavior, it seem a bit more complex. As if the signal from each neuron is moderated
than the +z vector (moving forward). Since this is a purely subjective observation and adjusted by the signals from another group of neurons. For example, when
from a very small number of field tests, I might be mistaken. But it is probably not someone points at something, we also look at the end of the finger—but only for
completely wrong. One winter, as a kid, I discovered that if I held two snowballs in as long as it takes to extrapolate the direction in which it’s pointing, then we move
my hand, I could—in rapid succession—throw the first one with a high and slow our gaze along that vector, searching for something interesting in its path. That
lob, and then throw the second in a fast and low trajectory, and hit my brother also goes for velocity vectors. Let’s say that I’m going to reach forward to grab
right in the puss while his attention still was on the first high snowball. And you something on the table. The velocity of the hand has a +z vector component, so
the hand will attract the spectator’s attention (fig.10). The spectator will look at

10 11 12 13

9 the hand just as long as is needed to extrapolate its speed and direction, then the
gaze will jump ahead to see where the hand is going (fig.11). After the target has
can try the following yourself: Face a friend as in figure 9A, then move both hands been identified, the eye is receptive to other visual stimuli and, if that is lacking,
simultaneously in a moderately rapid movement—one hand straight forward and the tendency is to look at the performer’s face (fig.12). Then, by the time the
one hand diagonally upward as in figure 9B. Try to make sure that the bottom spectator has extrapolated that the hand and its target will meet, his gaze returns
hand is vertically aligned with the top hand. Note which hand draws the most to the object (fig.13).
attention. And remember, try it on a friend, not on a stranger. Let’s go back to the hypothesis of curved motions again. The idea sprang from
an observation by Apollo Robbins, who certainly is no fool. While Macknik and
Martinez-Conde’s hypothesis is way off, Apollo’s initial observation is actually

23

correct—in some cases. And those cases are when the curved motion has a
positive y or z vector component, as in figure 1A, but not in the cases where the
y or z vector component is negative, as in figure 1B. To make this more clear, let
us simplify a curved trajectory by dividing it into three straight segments (fig.14).

17

14 15

Next, let us draw out the vector components (fig.15) and take a peek at what 18
we have. At the starting point of the trajectory, the +y vector component is very
prominent, which means that it will quickly catch the spectator’s attention. In Photo 17-19: John Nordling
the next segment, the +y vector component is less prominent, and in the third 19

segment it is hardly noticeable. In other The Russian group strikes a pose (fig.18), then walks over to the side of the stage
words, during the motion, the +y vector where they hold up a net to catch Charlie when he is fired out of the cannon. The
component is decelerating while +x plot is that he is going to catch a previously selected card in mid-flight, from a deck
vector component is accelerating. The of cards that is hoisted into the air just when the cannon goes off. The celebrity
velocity is in constant change, which guest lights the fuse (fig.19—by the way, the beautiful cannon was designed and
makes the motion less predictable built by Scott Penrose), but then something goes horribly wrong. Everyone rushes
and it takes longer for the spectator to forward to check for signs of life among the projected remains. One of the nurses
extrapolate what direction in which takes a closer step, then removes her surgical mask, flashing a wide grin—it is
they should look. As a comparison, I’ve Charlie in a nurse outfit.
16 divided a straight trajectory into three
segments (fig.16). As you can see, it is
enough to look at the first segment in order to extrapolate the next two segments.
So, what can this theorizing be used for? Well, instead of illustrating it with a
sleight-of-hand trick, let’s use a larger example. This summer I was a magic
consultant for Charlie Caper, who was one of the three magicians in Helt Magiskt
(the Swedish version of BBC’s The Magicians). One of the pieces he had decided to
perform went, in short, like this:
Charlie, dressed in a daredevil suit, is picked up by a Russian circus group and
loaded into a cannon (fig.17). Nearby there are two nurses, in case of an accident.

24

The basic idea that Charlie first thought of is illustrated in figure 20. Charlie has
somehow sneaked out of the cannon and is hidden in the wings (marked “C” in the
illustration). When the Russian team runs forward to see what has gone wrong,
they are used as cover for the leg drop switch between Charlie and the nurse
(marked “N” in the illustration). As it turned out, that didn’t work at all. Before the
Russian team had moved half the distance, the spectators had already extrapolated
the velocity of their movement and their eyes were open for other stimuli—for
20 example, the head of the nurse who moved in a different direction. The switch
was very noticeable. Since the switch would be framed out by the cameras, I knew
that a solution didn’t have to be YouTube proof. It just had to work for the studio
audience. So I decided to solve the problem with just movement vectors.
The first step was to apply Jonathan Pendragon’s “superimpose” improvement of
the leg drop switch. That is, instead of having the nurse simultaneously walk out
while Charlie walks in, the nurse stays put while Charlie walks out in front of her,
synchronized with the movements of the Russian team (figs.21 and 22). This is an
example of what was illustrated in figure 7 earlier.
21 To let the nurse exit unnoticed, we make use of Ramsay’s principle. The nurse
starts to walk (fig.23) the instant the Russian team turns to face the audience (“if
you want them to look at you, look at them”), and then they looked at the disaster
at the cannon (“if you want them to look at something, look at it yourself ”). This
would have been a beautiful solution, but unfortunately the set design worked
against us. Had it been a set with straight vertical leg drops, the switch would have
worked perfectly. But there was not a single straight angle in the set design of this
production (fig.24).

22
24

23

25

26

25

So, instead of instantly walking out of view after the switch, you could see the legs 27
of the nurse as she left (fig.25). Crap!
So, what to do? Simple! Add more vectors. Fortunately, the nurse moved along 28
the x-axis, meaning that it is simple to find vectors that are more attention-
grabbing. As the plot allowed for some unrest among the performers, I instructed Before leaving you, I want to take the opportunity to plug a new book I’ve written.
two people in the Russian team to exchange positions (fig.26). This provided two It is titled Maelstrom and I’m quite proud of it. That was the plug!
x-vectors on a higher z-plane than the nurse, just as in the example in figure 7. As usual, I often visit the Genii forum (www.geniimagazine.com/forums), so feel
That covered yet a part of the nurse’s exit, but not completely. Her feet were still free to comment and ask questions there.
in view. More vectors!
I directed a third person in the Russian team to take a step forward, directly after
the two other people had swapped positions (fig.27), getting a +z vector, and then
to raise her hands to her head in horror over the accident with the cannon—and
the hands gave us a +y vector. And by that time, the nurse had completed her exit
and was out of view. It was quite beautiful—even when I looked directly at it I
could not see the switch.
Sadly, this elegant solution got scrapped the day before the taping. A new director
decided to change the position of the Russian team with the net, moving them
closer and forward. I had to agree that it was a good change, as it made the overall
picture tighter and gave a better flow to the performance—but the vectors got all
screwy (fig.28) and I was not able to get 10 minutes of rehearsal time to analyze
and fix the new vectors. No real problem for the production, since the switch was
out of frame for the viewing audience anyway, but most of the studio audience
caught the switch. Pity.

26

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27

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