Over 2300 years ago, the Babylonians came up with the idea that the gods lived among the stars and other celestial objects, and were able to impose their will on humanity by controlling the destinies of individuals and nations alike. The Babylonians divided the sky into 12 “slices”: which we now know as the signs of the zodiac… Taurus, Pisces, etc. There are many variations of astrology, but they are all founded upon the idea that celestial objects can influence a person’s personality and destiny.
Today, according to a Gallup poll, 25% of American believes in Astrology. In this article, we’ll investigate why horoscopes and astrology sometimesappear to be correct by reviewing the concept of subjective validation, the Forer Effect, and Gauquelin’s famous horoscope experiment; we’ll take a look at what an astronomer has to say about astrology; we’ll review some of the logical issues with astrology; and finally, we’ll take a look at how easy it is to debunk horoscopes yourself.
Subjective Validation and the Forer Effect
“Subjective validation” occurs when two unrelated or random events are perceived to be related because a belief, expectancy, or hypothesis demands a relationship. Thus, people find a connection between the perception of their personality and the contents of their horoscope.
The concept of subjective validation was put to the test in 1948 by psychologist Bertram R. Forer. Forer gave a personality test to each of his students. Afterward, he told his students they were each receiving aunique personality analysis that was based on the test’s results, and to rate their analysis on a scale of 0 (very poor) to 5 (excellent) on how well it applied to themselves.
The analysis presented to the students was as follows:
You have a great need for other people to like and admire you. You have a tendency to be critical of yourself. You have a great deal of unused capacity which 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 outside, you tend to be worrisome and insecure 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. You have found it unwise to be too frank in revealing yourself to others. At times you are extroverted, affable, sociable, while at other times you are introverted, wary, reserved. Some of your aspirations tend to be pretty unrealistic. Security is one of your major goals in life.
The trick? In reality, each student received the exact same analysis: On average, the rating was 4.26/5(that is, the students found their “personal” analysis to be 85% accurate). It was only after the ratings were turned in was it revealed that each student had received identical copies assembled by Forer from various horoscopes.
As can be seen from the profile analysis, there are a number of statements that are vague and could apply equally to anyone. These statements later became known as Barnum statements, after P.T. Barnum, who used them in his performances, allegedly stating “there’s a sucker born every minute.”
Later studies have found that subjects give higher accuracy ratings if the following are true:
- the subject believes that the analysis applies only to him or her (for example, a horoscope)
- the subject believes in the authority of the evaluator (for example, a psychic)
- the analysis lists mainly positive traits (for example, most daily horoscopes)
Guaquelin’s Horoscope Experiment
In another experiment, the famous French Astrologer, Michael Gauquelin, offered free horoscopes to any reader of Ici Paris, if they would give feedback on the accuracy of his supposedly “individual” analysis. He wanted to scientifically test the profession of astrology. As with Forer’s experiment, there was a trick: he sent out thousands of copies of the same horoscope to people of various astrological signs – and 94% of the readers replied that his reading was very accurate and insightful.
What they didn’t know was that the horoscope was that of a local mass murderer, Dr. Petiot, who had admitted during his trial that he had killed 63 people. This is clearly another case of subjective validation where subjects focus on the hits of some general analysis that’s supposed to be unique to them.
An Astronomer’s Opinion
So what does science have to say about astrology?