Knock On Wood

"...magical thinking underlies a vast, often unseen universe of small rituals that accompany people through every waking hour of a day.

The appetite for such beliefs appears to be rooted in the circuitry of the brain, and for good reason. The sense of having special powers buoys people in threatening situations, and helps soothe everyday fears and ward off mental distress. In excess, it can lead to compulsive or delusional behavior. This emerging portrait of magical thinking helps explain why people who fashion themselves skeptics cling to odd rituals that seem to make no sense, and how apparently harmless superstition may become disabling."

The New York Times discusses the psychological study of "magical thinking." Read all about it here.