AS A MAGICIAN, James "The Amazing" Randi works hard to deceive his audience.
"I am a professional liar. A cheat. A charlatan. I am an actor who plays the part of a wizard," he says.
What, then, could he possibly offer scientists at the National Institute of Standards and Technology in Gaithersburg, more than 700 of whom packed an auditorium on government time recently to hear him.
Scientists, after all, are devout seekers of truth.
Not always, Randi told them.
And who better than a cheat and a charlatan to lecture on fraud and self-delusion in science?
"All scientists look at their lives and see a Nobel Prize just over the horizon," Randi says. Most are honest. But science is extremely competitive, and scientists "are just like anybody else -- they are capable of temporarily blinding themselves."
Many will be tempted, and a few will succumb to cutting corners, fudging the data or overlooking flaws in their experiments "because the end justifies the means, and they're defending some basic discovery," he says.
On the premise that it takes one to know one, Randi has made it his business in recent years to help expose bad science, as well as the practitioners of the supernatural, paranormal and occult.
"And I've made a good living at it," he says.
When German scientists recently persuaded their government to hire dowsers to search government buildings for "E-rays," supposed cancer-causing radiation of unknown origin that can only be detected by forked sticks, Randi turned up and showed that the dowsers couldn't find the same spot twice.
"Dowsing is one of the oldest forms of claptrap around, and it will always be with us," he said.
In France, a group of scientists announced that, to their own astonishment, they had confirmed the claims of homeopathic medicine that water retains the "memory" of substances that are no longer there.
By placing key documents on the laboratory ceiling, Randi says, he demonstrated that someone in the lab was secretly peeking at the codes that were supposed to keep the experiments honest, and then spiking the brew.
On TV and in books like "Flim Flam!" about the paranormal, and "The Faith Healers," Randi has exposed dowsers, faith-healers, ESP, UFOs, "psychic surgeons" and his favorite target, the spoon-bending psychic Uri Geller.
Randi's investigations and lectures before numerous scientific organizations have won him the respect of the scientific community. In 1986 he was awarded the MacArthur Foundation Prize for his investigation of supernatural claims, and in 1989 he won the Forum Award of the American Physical Society.
His ability to spot deception, he says, comes from decades of scheming to deceive.
In magic, he explains, "I have to use a trick. I have to be very much aware of how people's minds work. I have to know what they will expect, and how to misdirect their attention and lead them to a conclusion that is false."
It works, he says, because we all make assumptions every day that allow us to function. We assume that when the light is green, it's safe to go. And if the road looks like hard asphalt, we assume it probably won't swallow us up.
We develop these assumptions through a constant search for patterns in the things we observe, he says. But the patterns can be deceiving. And our willingness, even eagerness to read meaning into them can lead us astray, even get us into trouble.
Scientists in the crowd at NIST acknowledged privately, and a little self-consciously, how easy it is for researchers to run an experiment until they see the results -- the pattern -- they're looking for, and to dismiss all data that don't follow the pattern as the results of some experimental error.
On the whole, though, bad science is self-correcting. When the faulty work is published, and other scientists can't reproduce the results, they are dismissed as flawed.
But claims of the paranormal are less frequently subject to scientific scrutiny, and even when they are debunked, people are still all too willing to believe.
"People look for real magic because they're not satisfied with the answers they get" to the uncertainties in their lives, Randi says. "They spend most of their life trying to gain some advantage over things as they are . . . trying to remedy some vacancy in their life."
In the paranormal or the occult, they find comfort in a body of "knowledge" that most people don't have, and a long-sought clarity in their lives.
"Life is never that clear," Randi said. And he finds such gullibility "frightening."
"If somebody believes in something as apparently harmless as a horoscope," he says, "then that can be the edge of a very dangerous wedge."
Presidents such as Ronald Reagan who allow themselves to be guided by astrologers may make bad decisions, and sick people who rely on "psychic" healers may die. One of the latter was actor Peter Sellers, who chose psychic "surgeons" in the Philippines over a recommended heart bypass operation. By the time he finally consented to real surgery in 1980, it was too late. He died of heart disease.
More worrisome, Randi says, is the political power of people eager to accept easy explanations for events they can't understand, and unproven solutions for problems they can't control.
"Those people vote, and I want to have more people on my side who will not vote for the [David] Dukes or others who operate from principles that can be very harmful."