# Three Objects

This is a neat trick that can be performed with one victim and any three objects on a table.

The magician places an iPad, a mobile phone, and a media player on the table in front of a victim. He then secretly writes something on a piece of paper, and turns it over.

The magician invites the victim to choose two objects by placing her index fingers on them. The victim chooses the phone and media player. The magician then asks her to say 'right' or 'left'. The victim says 'right', and the magician tells the victim to pick up the media player her right finger is on, while he picks up the phone which had her left finger on.

The magician smiles smugly*, and hands the piece of paper to the victim, who reads: "I am holding the media player, you are holding the mobile phone, and the iPad is on the table".

#### The Maths

The effect of this trick is quite impressive. It seems that the magician can see the future, because apparently there could be no way he could have known how the victim would choose.

The probability of guessing correctly each of the three final locations is one-third. We might be tempted to leap to the conclusion that the probability of guessing all three is (1/3)3 = 1/27. However, the probability of guessing the first correctly is 1/3. The probability of guessing the second object is then 1/2. The final object held by the magician is 1/1. The probability therefore is not 1/27, but 1/3 x 1/2 x 1/1 = 1/6

That is still a long shot, so how does the magician do it time and time again?

The illusion is in the fact that although the choice of the victim is random, or may as well be, how it is interpreted is manipulable. The magician does not tell the victim what her hands are indicating when she chooses the two objects.

Let the objects be tab, vict and mago, named after their final positions. If the victim chooses vict and mago, the magician simply asks her to name one, and takes it if it is mago, and tells her to take it if it is vict.

If the victim instead chooses tab and vict, he takes the remaining mago. He then tells her to name one of the objects she is holding, and according to the choice he places that aside or invites her to take it. Either way, the victim ends up with vict.

I will leave it to you to work out how he manipulates the final possible combination.

##### Extension

It might be interesting to speculate how many objects it might be possible to do this for, and how many steps are possible. It also does not have to be just objects, but may involve any number of combinations and matching, such as envelopes with colours, containing messages to specific people who believe they are choosing freely. The effect is always stunning. Makes us wonder how many things in our daily lives are preordained, while leaving us the illusion of free choice?

*optional

# Chased

The magician invites the victim to stop him while he rifles through the card deck. The victim stops him, and takes the chosen card. The magician takes the card back into the deck, sandwiching it between the two halves of the deck he is holding, and hands the deck to the victim for safekeeping. He then proceeds to make a show of reading the victim's mind, asking some leading questions such as 'It is red, isn't it?', 'Higher than a 6', at each of which the victim confirms his visionary skill. Finally, the magician reveals he knows the card.

This trick is effective because immediately after the card is replaced in the deck, the victim has possession of the whole deck, so the usual suspect, of the magician using sleight of hand to bring it to the top or bottom cannot be the cause of his knowing the card. So, how does he do it?

#### Solution

You might be wondering why the trick is called 'chased'. Well, that is a clue to how it is done. The deck is prepared ahead of time in a certain sequence. A glance at the preceding card, on the bottom of the top half of the deck once the victim has selected her card, is enough for the trickster to work out what the next (chosen) card is.

The sequence we have chosen is the following: 'Chased' is an acronym to remember 'C - H - S - D', or 'clubs - hearts - spades - diamonds'. All the cards are placed in this sequence of suits. If a heart is seen as the bottom card of the first half of the deck, then the mago knows the chosen card must be the next suit in sequence, or spades.

So far, so good. But what about the number value of the chosen card? Well, that is done in any ascending arithmetric sequence. We think '3' is a good interval, and if the trickster shows the deck face up, the cards look random, despite the strict order, especially because the picture cards do not cluster, which they would do with 1 or 2 as the interval number. 4 would work just as well, but don't get too ambitious for the mental arithmetric requirements, unless you are a Ramanujan!

Each subsequent card is 3 higher than the previous card. For example, the deck would be arranged starting with a random choice: 4Hearts, this would be followed by 7Spades, then 10Diamonds, KingClubs, etc. The Ace counts as '1' and jack, queen, king as 11, 12, 13.

Note that the deck may be cut, but the cards may not be mixed. To make the trick totally baffling, the trickster can either switch a prepared deck for a victim shuffled deck, or he demonstrates his mastery of false shuffling, or both.

The knowledge of a chosen card can be utilised in many ways, of course. So 'Chased' is both a trick in itself and a technique to be used within a greater illusion. Enjoy!

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### Quote of the day...

"Zer trick," said Einstein, "ist to realise zat space-time ist not vat we dink it ist: it ist not fixed und immovable, but flopping about like ... ein big floppy ding."
"A rubber mattress?" suggested Sean.
"If zat ist your idea of a good time, ja."