Magic works because our brains are constantly filling in the gaps presented by the stimuli in our environment. If you're forced to look away during one of those gaps due to a distracting event or person for even half a second, by the time you look back, the magician will have created the illusion.
Most of us will never become talented enough to perform these sleights of hand in the fraction of a second necessary to carry them out successfully. Instead, you can put psychology to work for you to create effects that are guaranteed to work after one or two tries.
These tricks not only can amaze your friends, family, and co-workers or fellow students, but provide excellent classroom examples for teachers of high school or college psychology. You'll be amazed not only at their effectiveness, but by their simplicity. I'll show you how to perform each trick and, if you're interested, how the trick can be used for a psychology or science classroom demonstration.
Trick #1: Pick the Cards
Prepare 3 piles of cards:
Pile 1: 3 cards (any cards)
Pile 2: Four 3's (from all 4 suits)
Pile 3: 5 cards (any cards)
Put all these cards together IN THIS ORDER at the top of a deck to create the illusion that you are going to be randomly taking them off the top (though they will have been prearranged). Now tell your subject that you will use your magical psychic powers to predict which pile the volunteer will pick because your psychic powers are so strong. In fact, you're so good that you will write down your prediction ahead of time (stated as dramatically as possible). Without allowing the volunteer to see what you are doing, write down the number 3 on a large sheet of paper, fold it up, and then turn to the task at hand. Instruct the volunteer to think of a number and really concentrate. Close your eyes and pretend to be "sensing" what the volunteer is thinking. Then instruct the volunteer to point at the pile she or he has chosen. After pointing to any of the piles, say, "Yes, that is what I predicted! I have written down the number 3!!"
You have no chance of being wrong. Pile #1 had 3 cards, Pile #2 has all 3's, and the third pile is "Pile #3." Obviously, you don't reveal what your plan was or the effect will be spoiled.
For a class demonstration, you can, however, use this trick for educational purposes. After the applause dies down, ask the students if you have proven you are truly psychic. Of course they won't think you are, but now you can ask them to generate hypotheses about the secret of the trick. Through this process, you will be demonstrating the scientific method, the value of considering alternative hypotheses and being ready to critique a result even if it seems to be dramatically proving a point. Incidentally, hardly any one of the hundreds of students I have performed this trick in front of has ever guessed the secret. ( I want to thank my college Robert Feldman for showing me this trick)
Trick #2: Guess the Object
This trick involves a little more active deception and is best performed in front of several people. You will also need a "volunteer" (who you've chosen) to assist you. You can honestly ask this person in front of your audience whether you arranged ahead of time regarding which object was selected, and the honest answer will be "No." You will not have arranged ahead of time which object will be selected, but you did make another arrangement. You will arrange ahead of time which object the assistant will point to before whatever object the audience selects. This will be a black object. Any object that the volunteer points to after the black one will be the object chosen by the audience. As you can see, nothing is really left to chance at all, nor have you been dishonest.
Tell the class that you will step out of the room and they will have up until the time you count to 30 to choose the object. The assistant will be in the room during this time. Even if the object is black, you're still safe because it's the object after the black object that will be the correct one.
Return to the room and now tell the audience that you will need to have the volunteer point to several objects in the room. You will use your psychic powers to determine which object they have chosen. During this time, the volunteer will point to three or four objects, then to an object that is black. The object after the black one should be what the class selected.
It's even better if you ham this up. For each object, carefully inspect it, put your hands on it, look as though you are concentrating, and then announce in a loud voice, "No, this is definitely not the object." For one or two of the objects, you can start to say "yes," but then shake your head and say no. Chide the class and tell them to concentrate harder because you are getting confusing signals. For the object after the black one, first start to say no, then say very loudly, "YES! THIS IS THE OBJECT." Look at the audience and take a well-deserved bow.
For the class demonstration, you can inform the students that this experiment was a version of the so-called "Ganzfield procedure" procedure used in parapsychology labs to test the existence of ESP. As in the previous trick, encourage the students to think of alternative hypotheses.
Trick #3: Blink!
There is very little deception involved in this trick, just a little eye-hand coordination and the correct choice of a subject.
Collect these props: a small whistle and a squeezable "puff" maker (as is sold in ear wax cleaner kits).
Preferably, your volunteer should be a female, about your height, and she should not be wearing contacts. Have the volunteer stand squarely facing you, about one foot away. Set this up so that your audience can see her eyes. Announce that you will now show that you can use classical conditioning to make the volunteer blink her eyes in response to the whistle.
First, show that she will not blink when you blow the whistle alone but don't blow on the puff maker yet.
Then start the conditioning phase. Squeeze the puff maker while you blow the whistle. Make sure that you aim directly for her eyes each time. Pair the whistle with the air puff about five or six times. On the next trial, just blow the whistle. Have the observers verify that she blinked, and then take your bows and applause!
The classical conditioning effect is fairly reliable but you're covering your bets by creating the expectation that you will get a successful result. I prefer using a female volunteer because I find that they don't seem to resist the urge to blink quite as much as my male volunteers have in the past.
If you're using this as a class demonstration, you can then ask your students to review the relevant concepts by asking them to name the unconditioned stimulus (air puff), the conditioned stimulus (whistle), the unconditioned response (eye blink) and the conditioned response (also the eye blink!).
Trick #4: The Phenomenal Behavior Shaping Effect
Announce that you will now train a volunteer to do whatever it is you want without providing any instructions or directions. The behavior you will train in the volunteer should involve something silly but "clean" (no X-ratings here!).
Decide ahead of time what the behavior will be and have a prop ready. My favorite examples involve umbrellas, hula hoops, bicycles, or funny hats but almost anything will work. Whatever you choose, have the object sitting unobtrusively in the room so that it doesn't draw suspicion.