Illusions like the cups-and-ball routine can make simple trickery seem like the total suspension of space and time. Here's an insider's guide to the tools of the trade.

Distraction is key. "That's the game: getting people to focus attention in the wrong place, though you're doing it in front of their eyes," says Dan Simons, a visual cognition and perception expert at the University of Illinois at Urbana-Champaign. Attention is like a spotlight: We notice only what it's focused on.

Because people instinctively look where other people are looking, the magician gazes where he wants you to look, and your eyes follow.

A steady stream of verbal patter also provides camouflage. People have limited attention: Fill it with fast talk, and they're less likely to notice other details.

People have a tendency to see what they expect to see. "The magician pretends to throw a ball up in the air. People perceive the ball moving up, even though it never left his hand," explains Gustav Kuhn, a magician and research psychologist at the University of Durham in England. The harder you look, the less likely you are to spot the sleight.

For years, magicians have been a step ahead of the rest of us—including psychologists. But science is catching up. A sideshow benefit: seeing the hidden strings in everyday life. According to Kuhn, people should take care not to be tricked in more insidious ways, such as by salespeople who talk so fast that the fine print is forgotten. "There's a close link between magic and advertising."