At the core of every magic trick is a lie. When the silk has changed its color, when the chosen card has appeared, when the billiard balls have multiplied, rest assured that some lie has been told. The silk, the card, the balls--they do not tell the lie. The lie is not in the performance, but in the observation.

The hand is not quicker than the eye. On the contrary, it is the eye that is too quick, that jumps to conclusions. The hand moves quite deliberately, progressing step by step in patterns that the eye recognizes, until at last the eye supplies some steps of its own--steps that the hand never executes. Some motion is observed that is never made.

Any magician will tell you that the easiest audience to fool is the most intelligent one, the most well-educated. They have the quickest eyes, and make the most assumptions.