Geoffrey’s research tends to be methodologically similar to the work carried out by Hans Eysenck in that it usually involves examining large amounts of data in search of the patterns predicted by astrology. This is not, however, the only way to test the accuracy of planetary predictions. Other researchers have examined the claims made by individual astrologers. One of the most unusual, and striking, examples of this approach was reported by an American researcher in the late 1980s, in the provocatively titled article “Astrology on Death Row
.”
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The researchers first found out the birth time, date, and place of the notorious serial murderer John Gacy. Gacy was a sadistic killer who received twelve death sentences and twenty-one life terms for the torture and killing of thirty-three men and boys. Dressing up as
Pogo the Clown,
and performing at children’s birthday parties in his spare time, Gacy may have given rise to the notion of the “evil” clown. One of the researchers visited five professional astrologers and presented Gacy’s details as his own. The researcher explained to each astrologer that he was interested in working with young people and asked for a general personality reading and some career advice. The astrologers got it badly wrong. One encouraged the researcher to work with young people because he could “bring out their best qualities.” Another analyzed the information provided and confidently predicted that the researcher’s life would be “very, very, positive.” A third said that he was “kind, gentle, and considerate of others’ needs.”
The work of Hans Eysenck, Geoffrey Dean, and others show that heavenly predictions often fall far short of the mark. In doing so, they leave us with a bigger mystery: Why do so many people believe in astrology?
BERTRAM FORER AND THE NIGHTCLUB GRAPHOLOGIST
In the late 1940s, Bertram Forer was busy devising novel ways of measuring personality. One evening he visited a nightclub, where he was approached by a graphologist who offered to determine his personality on the basis of his handwriting. Forer declined the offer, but the chance encounter made him wonder why so many people were impressed with astrologers and graphologists. Forer could have carried on with his normal academic research. But curiosity got the better of him, and he decided to conduct an experiment. Long after his mainstream work on personality had faded into obscurity, he would still be famous for this unusual study.
Forer had the students in his introductory psychology class complete a personality test.
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One week later, each student was handed a sheet of paper and told that it contained a short description of his or her personality based on test scores. Forer asked the students to examine the descriptions carefully, assign them an accuracy rating by circling a number between 0 (poor) and 5 (perfect), and then raise their hands if they thought the test had done a good job of measuring their personalities.
Let’s turn back the hands of time and restage the experiment. Here is part of a description that was handed to students in Forer’s study. Read it through and see whether you think it a fairly accurate description of your own personality:
You have a need for other people to like and admire you. You have a tendency to be critical of yourself. You have considerable unused capacity that you have not turned to your advantage. While you have some personality weaknesses you are generally able to compensate for them. Disciplined and self-controlled on the outside, you tend to be worrisome and insecure on the inside. At times you have serious doubts as to whether you have made the right decision or done the right thing. You prefer a certain amount of change and variety and become dissatisfied when hemmed in by restrictions and limitations. You pride yourself as an independent thinker, and do not accept others’ statements without satisfactory proof. But you have found it unwise to be too frank in revealing yourself to others. At times you are extroverted, affable, and sociable, while at other times you are introverted, wary, and reserved. Some of your aspirations tend to be rather unrealistic.
Forer’s students read the description, made their ratings, and, one by one, raised their hands. After a few moments, he was surprised to see that virtually all the students had their hands up. Why was Forer so amazed?
As is sometimes the case with psychology experiments, Forer had not been entirely honest with his guinea pigs. The personality description he had handed them was not based on their test scores. Instead, it came from a newsstand astrology book that he had picked up a few days before. More important,
every student had received exactly the same personality description
—similar to the one that you read a few moments ago.
Forer had simply gone through the astrology book, selected about ten or so sentences from different astrological readings, and pasted them together to make one description. Even though they were all given the same personality description, 87 percent of students had circled either the number 4 or 5 on the rating scale, indicating that they were extremely impressed with the accuracy of what they had read. The reading Forer created has become world famous and has been used in thousands of psychology experiments and television shows.
Forer’s results solved the mystery that had been bugging him since his chance meeting with the graphologist. To be
seen
as accurate, astrology and graphology do not have to
be
accurate. Instead, you simply give people a general statement about personality and their brains will trick them into believing that it is insightful and individual.
Immediately after conducting his study, Forer told his students that they had all received the same personality description, explained that the exercise had been “an object lesson to demonstrate the tendency to be overly impressed by vague statements,” and pointed out the “similarities between the demonstration and the activities of charlatans.” Apparently, most of Forer’s students were not upset about being exposed as a tad gullible. Many of them bestowed on the psychology experiment the greatest honor that a student can give: They asked Forer for a copy of the personality description so that they could play the same trick on their friends. Most psychologists would have left it there, but Forer devised one last twist in a final attempt to inflict further humiliation on his long-suffering class.
Forer wondered whether his students would want to see themselves as astute, streetwise, and smart. If so, would their acceptance of vague personality statements have presented a challenge to this aspect of their self-identity? Moreover, rather than go through the painful process of seeing themselves as they really are, would they take the easy option of simply denying to themselves that they were taken in by the demonstration?
Three weeks later, Forer told his class that he had inadvertently erased their names from the rating sheets and asked them to jot down honestly the ratings they had assigned the original description. He had not lost the names at all, and so he was able to compare the ratings the students had originally given the description with the ratings they subsequently claimed they had given it. Half the students who had
originally
indicated that they thought the description was “perfect” (assigning it the maximum score of 5) subsequently claimed that they had given it a lower rating. It seems that the most gullible people would rather fool themselves than face up to their gullibility.
ENTER PHINEAS TAYLOR BARNUM
In the 1950s, the psychologist Paul Meehl christened Forer’s original finding the “Barnum Effect,” after the American showman Phineas Taylor Barnum, who once famously said that any good circus should have something for everyone.
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Years of research have shown that almost everyone is susceptible to the Barnum Effect—men and women, young and old, believers in astrology and skeptics alike, students, and even human resources managers.
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One of the most interesting follow-up studies was conducted by the French researcher Michel Gauquelin.
21
Gauquelin sent the birth details of Dr. Marcel Petiot, a notorious French mass murderer, to a firm that used high-tech computers to generate allegedly accurate horoscopes. During World War II, Petiot told his victims that he was able to help them escape from Nazi-occupied France, but instead administered a lethal injection and watched them slowly die. Petiot, who later pleaded guilty to nineteen murders, was guillotined in 1946. The computerized horoscope managed to miss all the grisly aspects of Petiot’s life and instead generated the same type of bland Barnum statements that had been used to such great effect by Forer, including:
His adaptable and pliant character expresses itself through skill and efficiency; his dynamism finds support in a tendency towards order, control, balance. He is an organized and organizing person socially, materially and intellectually. He may appear as someone who submits to social norms, fond of propriety and endowed with a moral sense which is comforting—that of a worthy, right-thinking, middle-class citizen.
Although Petiot was executed in 1946, the horoscope predicted that between 1970 and 1972 he would experience “a tendency to make commitments regarding his romantic life.”
Inspired, Gauquelin then offered free, computer-generated horoscopes through an advertisement he placed in a well-known newspaper. More than 150 people from all over France responded, and Gauquelin sent each one the reading based on the birth details of Petiot. He also asked them to rate the degree to which the horoscope presented an accurate description of their personalities. Ninety-four percent of recipients said that it was accurate. One person wrote to Gauquelin, noting: “The work done by this machine is marvellous . . . I would go so far as to say extraordinary.” Another wrote, “It is absolutely bewildering that an electronic machine is able to probe people’s character and future.” Some people were so impressed that they offered to pay Gauquelin for a more detailed analysis.
So why are so many people taken in by these types of readings?
People endorse many of the statements because they are true for the vast majority of the population. After all, who hasn’t had serious doubts about an important decision, would deny wanting other people to admire them, or doesn’t strive for a sense of security? Even specific-sounding statements can be true of a surprisingly large percentage of the population. A few years ago, Susan Blackmore, a psychologist and a colleague of mine, conducted a survey in which she asked approximately 6,000 people about the sorts of seemingly specific statements that crop up in psychic readings, such as, “You have someone in your family named Jack.”
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She discovered that about a third of her subjects had a scar on the left knee, another third owned a tape or CD of Handel’s
Water Music,
a fifth had a “Jack” in the family, and about one in ten had spent the previous night dreaming about someone they hadn’t seen for years. It seems that many Barnum statements appear accurate because most people tend to think and behave in surprisingly predictable ways.
Then there is the “flattery effect.” Most people are more than willing to believe anything that puts them in a positive light, and thus they endorse statements suggesting that they have a great deal of unused capacity or are independent thinkers. This effect explains why half the population is especially accepting of astrology. The twelve signs of the zodiac are traditionally split into the six “positive” signs (Aries, Gemini, Leo, Libra, Sagittarius, and Aquarius) and six “negative” signs (Taurus, Cancer, Virgo, Scorpio, Capricorn, and Pisces). The traits associated with the positive signs tend to be more favorable than those associated with the negative signs. Those born into Libra are traditionally seen as the type of people who seek peace and beauty, but Taureans are viewed as more materialistic and easily upset. Margaret Hamilton, a psychologist from the University of Wisconsin, asked her subjects to give their dates of birth and to rate the degree to which they believed in astrology on a seven-point scale. As predicted by the “flattery effect,” those born under “positive” signs were significantly more likely to believe in astrology than those born under “negative” signs.
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The work of Forer, and those who have followed in his footsteps, demonstrates how horoscopes have fooled millions of people over thousands of years. Astrologers can produce any old rubbish and, providing it is sufficiently vague and flattering, most people will tick the “highly accurate” box. So, given that the scientific evidence in favor of astrology is less than overwhelming, it would be tempting to conclude that there is no real science associated with a person’s date of birth.
Tempting, but wrong.
THE SCIENTIFIC STUDY OF TIME AND MIND
Chronopsychology is a new, and still relatively obscure, scientific discipline devoted to the study of time and mind. Much of the work in this area is concerned with circadian rhythms, shift work, and jet lag.