Excerpted with permission from Michael Shermer, "How We Believe: The Search for God in an Age of Science." New York: W. H. Freeman, from Chapter 3. The Belief Engine.

Throughout much of 1998 and 1999, the best-selling book in America was by aman who says he can talk to the dead (and so can you, if you buy his book).It turns out that our loved ones who have passed over are not really dead,just on another spiritual plane.

I am referring to James Van Praagh, the famous medium. According to his own web page

, "Van Praagh is a survival evidence medium, meaning that he is able to bridge the gap between two planes of existence, that of the living and that of the dead, by providing evidential proof of life after death via detailed messages." VanPraagh calls himself a "clairsentient," or "clear feeling," where he canallegedly "feel the emotions and personalities of the deceased." He claims that the "spirits communicate by their emotions," and even though they do not speakEnglish or any other language, they can tell you, for example, "that youchanged your pants because of a hole in the left seam or that you couldn'tmail letters today because the stamps weren't in the bottom right deskdrawer."

He readily admits that he makes mistakes in his readings (there areso many he could hardly deny it), rationalizing it this way: "If I conveyrecognizable evidence along with even a fraction of the loving energy behindthe message, I consider the reading successful."

I once sat in on a day of readings with Van Praagh and kept a running tallyof his ratio of hits and misses for each of ten subjects (one of whom was me,all filmed for NBC's "Unsolved Mysteries"). Being generous with what kind ofinformation counted as a "hit," Van Praagh averaged 5-10 hits for every 30questions/statements, or 16-33 percent. But because Van Praagh's payoffis the hope of life after death and a chance to speak with a lost loved one,people are exceptionally forgiving of his many misses.

Watching James Van Praagh work a crowd or do a one-on-one reading is aneducational experience in human psychology. Make no mistake about it, this isone clever man. Van Praagh masterfully uses his ability and learned skills in three basic techniques he uses to "talk" to the dead:

1. Cold Reading. Most of what Van Praagh does is what is known in thementalism trade as cold reading, where you literally "read" someone "cold,"knowing nothing about them. He asks lots of questions and make numerousstatements, some general and some specific, and sees what sticks. Most of thetime he is wrong. His subjects visibly nod their heads "no." But he onlyneeds an occasional strike to convince his clientele he is genuine.

2. Warm Reading. This is utilizing known principles of psychology that applyto nearly everyone. For example, most grieving people will wear a piece ofjewelry that has a connection to their loved one. Katie Couric on The TodayShow, for example, after her husband died, wore his ring on a necklace whenshe returned to the show. Van Praagh knows this about mourning people andwill say something like "do you have a ring or a piece of jewelry on you,please?" His subject cannot believe her ears and nods enthusiastically in theaffirmative. He says "thank you," and moves on as if he had just divinedthis from heaven. Most people also keep a photograph of their loved oneeither on them or near their bed, and Van Praagh will take credit for thisspecific hit that actually applies to most people.

Van Praagh is facile at determining the cause of death by focusing either onthe chest or head areas, and then exploring whether it was a slow or suddenend. He works his way down through these possibilities as if he werefollowing a computer flow chart and then fills in the blanks. "I'm feeling apain in the chest." If he gets a positive nod, he continues. "Did he havecancer, please? Because I'm seeing a slow death here." If he gets the nod,he takes the hit. If the subject hesitates at all, he will quickly shift toheart attack. If it is the head, he goes for stroke or head injury from anautomobile accident or fall. Statistically speaking there are only half adozen ways most of us die, so with just a little probing, and the verbal andnonverbal cues of his subject, he can appear to get far more hits than he isreally getting.

3. Hot Reading. Mentalist Max Maven informs me that some mentalists andpsychics also do "hot" readings, where they obtain information on a subjectahead of time. I do not know if Van Praagh does research or uses privatedetectives to get information on people, but I have discovered from numeroustelevision producers that he consciously and deliberately pumps them forinformation about his subjects ahead of time, then uses that information todeceive the viewing public that he got it from heaven.