Humans are meaning-hungry animals. We've spent centuries building intellectual edifices and metaphysical systems to try to make sense of the universe. But sometimes science, myth, religion, and philosophy don't suffice. They feel too remote, or inadequate. Besides, it's quite unlikely that any of them will tell you whether that guy was being rude or just oblivious.
Enter astrology, the belief that the positions of celestial bodies at certain key moments (like the time of one's birth) can predict or explain personality traits, historical tendencies, and world events.
A modern audience, bolstered by young people and vulnerable social groups, has embraced the ancient art of astrology. This global phenomenon is projected to be valued at about $23 billion (756.2 billion baht) in the next five years.
It's easy to see the appeal. The practice is highly customisable. The simplest are bald-faced sun-sign descriptions: stubborn Aries, dependable Taurus. Full astrological charts may contain tens or even hundreds of signifiers -- the position of the planets, the angles between them, the ascendant, asteroids, houses, etc. Each one adds a new layer of nuance to explore, a new story to tell: the sun in Capricorn suggests conservatism, but the ascendant in Aquarius creates a tendency to the unconventional.
If only those stories described real things in the real world. But they don't. At best, they're projective, and at worst, they're completely false and misleading, even dangerous.
When researching my new book, What Science Says About Astrology, I found that the usual objections to astrology tended to appeal to considerations that are astronomical (the stars aren't where astrologers say they are), astrophysical (there's no force in nature capable of creating the effects astrology demands), or logical (how can people with identical birth charts have different lives and personalities?). But I discovered that there's also a strong empirical argument to be made: When we try to use dispassionate data to support astrological predictions, we come out empty-handed.
As a teenager, I tried calculating my birth chart -- twice, because I used some incorrect data the first time. To my surprise, though, both readings made perfect sense. This was my introduction to the "empty vessel" effect, where one can pour one's own preexisting intuitions, prejudices, opinions, and self-image into any reading.
I found countless documentations of this "empty vessel" effect throughout the history of astrology. One especially egregious example occurred in 1968, when the psychologist and astrology researcher Michel Gauquelin posted an advertisement in the French magazine Ici Paris. Posing as the fictitious Astral Electronics, Gauquelin promised to send free, computer-generated astrological profiles to anyone who would agree to furnish their name, address, and place, date, and time of birth.
Gauquelin sent each of the respondents the same reading: the birth chart of Marcel Petiot, one of the most infamous serial killers in French history. He also included a questionnaire that asked for feedback. To the questions "Did you recognise yourself in the psychological portrait sent you? Did you recognise any of your personal problems?", 94% of responses were positive. To "Is your opinion shared by your family and friends?", 90% answered "yes".
The survey confirmed what Gauquelin and other psychologists had suspected for decades. Astrological pronouncements tend to use language in a way that is objectively quite open-ended and generic, to the point of tautology or even meaninglessness. But they also can be read, subjectively, as very pointed and personal.
One example, collected from an astrology book by psychologist Bertram Forer in the 1940s, is the statement, "You have a great deal of unused capacity which you have not turned to your advantage." The line not only applies to almost everyone, but it also applies to everyone specifically: my "unused capacity" is probably not the same as yours, and our concepts of what it would mean to "turn [it] to [my] advantage" may also diverge quite a lot: to find a romantic partner? to make money? to launch or advance a career? The reader fills in the gaps almost unconsciously and feels a personal touch that, in reality, never existed.
That's a process called subjective validation. Closely associated with subjective validation is confirmation bias, the psychological tendency to give more weight and attention to events that seem to validate our beliefs and intuitions, and to disregard, ignore, or explain away any counterexamples.
Both scientists and tech-savvy astrologers made prodigious attempts to use statistics to validate astrology throughout the computerised 20th century. If astrological tenets have a basis in reality, there should be observable effects in the world -- an excess of married couples with compatible astrological configurations, for instance, or a predominance of people from assertive and sanguine signs in more risk-taking careers. Also, astrologers should be able to associate biographies with birth charts correctly more often than not. Distinguishing the horoscopes of ordinary citizens from those of serial killers should be as straightforward as medical doctors correctly connecting lab test results to patients' symptoms.
But of the hundreds of studies conducted in the last 120 years, the data does not show any legitimate astrological effect in the world. Not every single test comes back negative, but there's a pattern that is common to pseudosciences in general: the better the quality of the study, the more stringent the controls against delusion or fraud, the less impressive the results. Astrologers tend to cling to the few, flawed results that seem to show some effect, or to just cop out, saying that astrological claims are somehow beyond science's reach.
It is only fair to add that there are studies, usually consisting of interviews with astrology enthusiasts, that point to perceived psychological and emotional benefits for users -- like enhanced self-cohesion, and a sense of community, belonging, and identity. But it is important to note that even such works warn against "excessive use".
Yet astrology has maintained its relevance for centuries. It offers a mythic overlay to be superimposed on the humdrum of our ordinary lives, a map for meaning that may comfort and reassure us. Back in ancient Rome, when the fate of the empire often hung in the balance of palace conspiracies and assassination plots, astrologers' pronouncements could strengthen the resolve of a conspirator or assuage the paranoid feelings of the ruling emperor. But their advice was often more misleading than helpful. History shows us that astrology's maps of meaning have always been spurious, leading down fantasy trails and hiding very real pitfalls. Today, we have the science to prove it. Zócalo Public Square
Carlos Orsi is a prize-winning science journalist with a career of more than 30 years and author of 'What Science Says About Astrology'.
