This is a variation of David Parr's Proof Positive which is a variation of Max Maven's Positive/Negative. It uses equivoque as well as a method of turning a coin between heads or tails within a clenched hand.
The Dime is in the hand.
Script:
Andy, would you say that you have a vivid imagination?
Yes.
Good, that will come in handy.
In a moment I will place an object in my left hand. The reason I'm telling you this is that later you might wonder if there really was an object under my left hand or you might wonder if there was actually more than one object. So, to dispel any suspicions you might have, I promise to keep my hand here until it is time to reveal what is in it. Does that seem fair?
Yes
Good. Now here is where your imagination comes in. I want you to imagine there are three coins on the table in front of you. There's a nickle, there's a dime and there's a quarter. Nickle, dime, quarter. With your right hand I want you to pick up one of those coins.
(picks up coin)
Scenario 1
Which is that? The dime. Ok, now flip it into the air so that lands on the table. Now you tell me, did the dime land tails up or heads up? (tails/heads) Did you say (tails/heads)? That's amazing! You'r absolutely right. The dime is (tails/heads) side up!
Scenario 2
Which is that? The nickle. And with your left hand pick up a second coin. And which is that. The quarter. Ok, those coins are yours to keep. I will take the dime and flip it so that it lands on the table. Now you tell me, did the dime land tails up or heads up? (tails/heads) Did you say (tails/heads)? That's amazing! You'r absolutely right. The dime is (tails/heads) side up!
Scenario 3
Which is that? The nickle/quarter. And with your left hand pick up a second coin. And which is that. The dime. Hand one of the coins to me. (if he hands you the nickle/quarter) Now take the dime and flip it ...
(if he hand you the dime) and I will flip it...
David Parr traps the coin vertically between his hand and the table. When the side of the coin is revealed by the participant, he simply lets the coin fall flat either heads or tails up. The problem that I have with this is that the falling of the coin is noisy, even if the table has a table cloth. In a quiet room this is a dead giveaway. To deal with this problem I simple place the coin in my hand so that it is held vertically between the fold of my palm and middle finger. I can then open my hand controlling whether the coin is heads or tails.
