92 P H V SIC S OF THE IMPOSSIBLE
of the Parapsychology Association, she was fascinated by ESP and conducted many studies on her own students at the college. She used to
scour cocktail parties where famous psychics would perform psychic
tricks in front of the dinner guests, in order to recruit more subjects for
her experiments. But after analyzing hundreds of students and scores
of mentalists and psychics, she once confided to me that she was unable to find a single person who could perform these psychokinetic
feats on demand, under controlled conditions.
She once spread around a room tiny thermistors that could measure changes in temperature to fractions of a degree. One mentalist
was able, after strenuous mental effort, to raise the temperature of a
thermistor by a tenth of a degree. Schmeidler was proud that she could
perform this experiment under rigorous conditions. But it was a far cry
from being able to move large objects on demand by the force of one's
mind.
One of the most rigorous, but also controversial, studies on psychokinesis was done at the Princeton Engineering Anomalies Research (PEAR) Program at Princeton University, founded by Robert G.
Jahn in 1979 when he was serving as dean of the School of Engineering and Applied Science. The PEAR engineers were exploring whether
or not the human mind by thought alone was capable of affecting the
results of random events. For example, we know that when we flip a
coin, there is a 50 percent probability of getting heads or tails. But the
scientists at PEAR claimed that human thought alone was capable of
affecting the results of these random events. Over a twenty-eight-year
period, until the program was finally closed in 2007, engineers at
PEAR conducted thousands of experiments, involving over 1.7 million
trials and 340 million coin tosses. The results seemed to confirm that
the effects of psychokinesis exist-but the effects are quite tiny, no more
than a few parts per ten thousand, on average. And even these meager
results have been disputed by other scientists who claim that the researchers had subtle, hidden biases in their data.
(In 1988 the U.S. Army asked the National Research Council to investigate claims of paranormal activity. The U.S. Army was anxious to
explore any possible advantage it could offer its troops, including psy-
of the Parapsychology Association, she was fascinated by ESP and conducted many studies on her own students at the college. She used to
scour cocktail parties where famous psychics would perform psychic
tricks in front of the dinner guests, in order to recruit more subjects for
her experiments. But after analyzing hundreds of students and scores
of mentalists and psychics, she once confided to me that she was unable to find a single person who could perform these psychokinetic
feats on demand, under controlled conditions.
She once spread around a room tiny thermistors that could measure changes in temperature to fractions of a degree. One mentalist
was able, after strenuous mental effort, to raise the temperature of a
thermistor by a tenth of a degree. Schmeidler was proud that she could
perform this experiment under rigorous conditions. But it was a far cry
from being able to move large objects on demand by the force of one's
mind.
One of the most rigorous, but also controversial, studies on psychokinesis was done at the Princeton Engineering Anomalies Research (PEAR) Program at Princeton University, founded by Robert G.
Jahn in 1979 when he was serving as dean of the School of Engineering and Applied Science. The PEAR engineers were exploring whether
or not the human mind by thought alone was capable of affecting the
results of random events. For example, we know that when we flip a
coin, there is a 50 percent probability of getting heads or tails. But the
scientists at PEAR claimed that human thought alone was capable of
affecting the results of these random events. Over a twenty-eight-year
period, until the program was finally closed in 2007, engineers at
PEAR conducted thousands of experiments, involving over 1.7 million
trials and 340 million coin tosses. The results seemed to confirm that
the effects of psychokinesis exist-but the effects are quite tiny, no more
than a few parts per ten thousand, on average. And even these meager
results have been disputed by other scientists who claim that the researchers had subtle, hidden biases in their data.
(In 1988 the U.S. Army asked the National Research Council to investigate claims of paranormal activity. The U.S. Army was anxious to
explore any possible advantage it could offer its troops, including psy-