An illusion is a malformation of the senses, disclosing how the brain normally organizes and interprets sensory stimulation.Illusions may occur with any of the human senses, but visual illusions (optical illusions) are the best-known and understood. The emphasis on visual illusions occurs because vision often governs the other senses. Other illusions occur because of biological sensory structures within the human body or conditions outside of the body within one’s physical environment.
The term illusion refers to a specific form of sensory distortion. Unlike a hallucination, which is a distortion in the absence of a stimulus, an illusion describes a misinterpretation of a true sensation. For example, hearing voices regardless of the environment would be a hallucination, whereas hearing voices in the sound of running water (or other auditory source) would be an illusion.
Magic is a performing art that entertains an audience by creating illusions of impossible or supernatural feats, using purely natural means. These feats are called “magic tricks,” “effects,” or “illusions.” An artist who performs magic as illusion or entertainment is called an illusionist or a magician, just as those who perform sorcery also are called magicians.
Illusionists have been popular as entertainers throughout history. They have maintained great secrecy about their art, revealing their tricks only to trusted apprentices. The illusionists’ strict code appears justified by the fact that there exists some danger in their acts, as evidenced by many of their number suffering serious, even fatal, accidents. Equally, misuse of their secrets for personal gain with little entertainment value cheapens their craft.
In ancient times, Greeks and Persians had been at war for centuries, and the Persian priests, called magosh in Persian, came to be known as magoi in Greek. The first book containing explanations of magic tricks appeared in 1584. During the 17th century, many similar books were published that described magic tricks. Until the 18th century, magic shows were a common source of entertainment at fairs. A founding figure of modern entertainment magic was Jean Eugene Robert-Houdin, originally a clockmaker, who had a magic theatre in Paris in 1845. John Henry Anderson was pioneering the same transition in London in the 1840s. Towards the end of the 19th century, large magic shows permanently staged at big theatre venues became the norm. During the 19th and 20th centuries, many stage magicians even capitalized on this notion in their advertisements. The same level of ingenuity that was used to produce famous ancient deceptions such as the Trojan Horse would also have been used for entertainment, or at least for cheating in money games. However, the profession of the illusionist gained strength only in the 18th century, and has enjoyed several popular vogues since. generally agreed that there are very few different types of illusions. Perhaps because it is considered a magic number, it has often been said that there are only seven types of illusion:
The magician pulls a rabbit from an empty hat; a fan of cards from “thin air;” a shower of coins from an empty bucket; or appears in a puff of smoke on an empty stage; all of these effects are “productions,” where the magician produces “something from nothing.”
The magician snaps his fingers and a coin disappears; places a dove in a cage, claps his hands, and the bird vanishes including the cage; stuffs a silk into his fist and opens his hands revealing nothing, or waves a magic wand and the Statue of Liberty magically “goes away.” A “vanish,” being the reverse of a production, may use a similar technique, in reverse.
The illusionist pulls a red handkerchief through his fist twice, which suddenly turns blue on the third pass. A spectator is shown a penny to hold in a closed fist. After squeezing it tightly, it miraculously becomes a dime in the spectator’s hand. A magician requests a volunteer to “pick a card, any card” from a deck. With a flourish the magician shows the card to the volunteer and asks “is this your card?” It is not the right card, but the magician tells the volunteer, “here, hold it for a second,” handing them the card and then picking card after card from the deck, none of which is the card the volunteer picked. The magician asks, “Will you look at that first card again?” whereupon the volunteer finds the card in their hand to have magically become their card.
A rope is cut into two pieces, the two pieces are tied together, and the knot mysteriously vanishes, leaving one unbroken piece of rope. A newspaper is torn to bits. The magician rubs the pieces together and the newspaper becomes whole. A woman is sawn into two separate parts and then magically rejoined. A card is torn in fourths and then restored piece by piece to a normal state. “Restorations” put something back into the state it once was.
A “teleportation” transfers an object from one place to another. A coin is vanished, then later found inside a tightly bound bag, which is inside a box that is tied shut, inside “another” box, which is in a locked box,all of which were on the other side of the stage. The magician locks his assistant in a cage, then locks himself in another. Both cages are uncovered and the pair have magically exchanged places, creating a “transposition”: a simultaneous, double teleportation.
The magician “puts his assistant into a trance” and then floats him or her up and into the air, passing a ring around his or her body as proof that there are ‘no wires’ supporting them. A close-up artist wads up your dollar bill and then floats it in the air. A playing card hovers over a deck of cards. A penny on an open palm rises onto its edge on command. A scarf dances in a sealed bottle. “Levitations” are illusions where the conjurer “magically” raises something into the air.
“Penetration” is when one solid object passes through another, as in such old standbys as “the Linking Rings” (a magical effect the magician creates by seemingly passing solid steel rings through one another) and “Cups and Balls” (in which the balls appear to pass through the bottom of an inverted cup to the table below).