In the 1990s it was "Touched by an Angel." Then it was John Edward's "Crossing Over." Now it's the increasingly popular "Medium" and "The Ghost Whisperer." Americans have always seemed fascinated by the idea of communicating with spirits in another world. According to a recent study by the Baylor Institute for Studies of Religion, 20 percent of Americans believe that the living can communicate with the dead. In an online survey of 10,000 Beliefnet members, 77 percent said they'd felt the presence of a spirit, angel or dead soul.

Both the survey results and the TV statistics indicate that women are more likely to believe it's possible to interact with the spirit world. Forty-six percent of women surveyed believed that "the souls of the dead protect the living as spirit guides," compared with 27 percent of men. Women were also more likely than men to believe that "the dead can hear our prayers or intercede with God on our behalf."

Most interesting, people tend to view these spirits as protectors who may intervene to help in their daily lives. Forty-two percent in the Beliefnet survey said the souls protect the living by acting as guardian angels or spirit guides. Can you communicate with the dead only if you're a psychic—or a TV star? Thirty-six percent of Beliefnet poll respondents believed that talking to the dead is "something that everyone has potential for."

All this interest in communicating with the dead comes despite the fact that Jews and Christians have prohibitions against it.

The Bible says, "There shall not be found among you any one that consulteth a ghost or familiar spirit, or a necromancer" (Deut. 18:10). One respondent captured a common Christian view when he said the appearance of a loved one is "the Devil in disguise." These spirits are "simply a way to try to move us away from our close relationship with God."

Not everyone buys the idea that the living and the dead can connect. Atheist Michael Shermer believes people are so eager to communicate with those beyond the grave that they're willing to interpret signs creatively. Deborah Blum, professor of science journalism at the University of Wisconsin, suggests that science might do better to try to explain paranormal activity rather than dismiss it. "We should never be so arrogant as to assume that one group knows everything," she cautions. "I don't think this interest [in talking to the dead] is ever going away."