Tech UPTechnologyThese are the tests that show that astrology does...

These are the tests that show that astrology does not predict anything

Since the 1960s it has been systematically proven that astrologers are unable to discern the most obvious personality traits in the charts they produce. In 1961 Vernon Clark demonstrated, in a test involving some of the world’s best astrologers, that they failed to match the charts of patients with their medical records . In 1975 Macharg found that same inability analyzing letters from alcoholics.

At least 10 scientific studies show that astrologers don’t even agree on what a birth chart means. The most striking test is from 1986, when German psychologists U. Timm and T. Koberl analyzed data from a study conducted with 178 German astrologers (the largest sample of astrologers ever tested) between 1952 and 1955 by a center dedicated to research in parapsychology, Hans Bender’s Institute for Frontier Areas in Psychology .

The study was never published by this pro-paranormal organization, and it is not difficult to understand why: the analysis, carried out 3 decades later, showed that astrologers, studying an average of five charts, did not show any agreement in their interpretations . If all the studies carried out to date show, without a margin of doubt, that astrologers do not agree on anything when interpreting a birth chart, what value does astrology have ?

In 1990, psychologists from Indiana University led by John McGrew and Richard McFall asked 6 astrologers from the Indiana Astrological Association to study the birth chart of 23 subjects, all aged between 30 and 32 years, to choose the psychological profile that better suited her. On a scale of 0 to 100, each participating astrologer was 75% sure of getting it right: the truth was that they got very little right than expected by chance. And more interesting still, the agreement between the astrologers was nil ; that is, there was not even a coincidence when assigning a certain astral chart to a psychological profile, something to be expected if astrology were really coherent. In a subsequent study, five groups of between 5 and 6 astrologers studied a subset of 5 charts and achieved 2 successes, worse than the 5 expected by chance alone.

In 1996 Rob Nanninga did something similar with 60 astrologers: they had to choose the correct psychological profile of 7 volunteers born “around 1958”. This was determined through a classic personality test to which was added a series of questions about their education, vocations, hobbies, health and religion proposed by the astrologers themselves. Once again the results put astrology back in a bind. Finally, in 2009 Stuart Wise and AJ Wyman asked 52 psychology students to identify between two psychological profiles (made with the NEO Five-Factor Inventory) which was theirs and, furthermore, to distinguish the correct profile from a false one obtained through a program business that made astrological charts. In this last case, the researchers suppressed all reference to astrological terms such as sign, house, planet… The students had no problem finding their correct psychological profile but systematically failed when choosing the astrological one.

But there is no doubt that the most famous and detailed research that put astrology to the test was that carried out by Michel Gauquelin between 1949 and 1991. This French psychologist used large samples, sometimes reaching more than 100,000 people, all them with the time, place and date of birth obtained from birth certificates. His work resulted in several books and almost 150 scientific articles: all attempts made to test astrological claims about signs, aspects and transits were invariably negative.

Gauquelin also put astrologers to the test in what he called “the experiment of opposite destinies.” He provided astrologers with the dates of birth of 40 people, 20 criminals and 20 peaceful citizens: none were able to differentiate between them from their birth chart. In 1983 Gauquelin wrote: “astrologers fail these tests and are sometimes so disappointed that they accuse me of rigging the results.”

And what about his public predictions? Astrologers claim that they are capable of predicting the political and economic future of countries, companies, wars… But is it true? In 1978 two members of the US Geological Survey, Hunter and Derr, invited the population to send in their earthquake predictions as part of a general evaluation of the different prediction systems. Astrologers responded to this invitation in the largest number: 240 earthquake predictions made by 27 astrologers. His hits were much lower than those obtained by chance . The following year Roger Culver and Philip Ianna analyzed 3,011 specific predictions made during 1974-1979 in American astrological journals such as American Astrology , and found that only 338 (11%) were correct. “Many of these could be attributed to ‘astute’ guesses (East-West tension will continue), vagueness (a tragedy will rock the eastern United States this spring), or social information (star A will marry director B).” commented critical astrologer Geoffrey Dean. Chatillon found the same thing in 1985 when he studied 30 specific predictions for North America made in 1984 by Huguette Hirsing, one of Montreal’s most famous astrologers. He only got two right (7%).

The clearest example of astrology’s inability to see the future is that no astrologer predicted the fall of the Berlin Wall, 9/11, 3/11, or the war in Ukraine. But one of the great fiascoes of astrology is in the hands of one of the most prestigious European astrologers of the 20th century, André Barbault, a specialist in ‘political astrology’: he predicted the end of the Franco-Algerian war 11 times (at the end was right) and his predictions for a dozen world leaders included many major blunders, such as that Kennedy would be re-elected in 1964 (he was assassinated in 1963), Khrushchev would remain in power until 1966 (he was deposed in 1964), de Gaulle would resign in 1965 (he was re-elected)… As one critic put it, “what was announced did not happen, what happened was not announced.”

What has been the response of astrologers to the enormous accumulation of studies that debunk any pretense of validity of their discipline? Most are silent for an answer and look the other way. A few try to find ‘ad hoc’ reasons to explain the debacle: the astrologers used in the studies were not ‘good’, the sample was not large enough for a clear assessment, astrology is very complicated, that is, it is impossible scientifically proven…

Now, if, as happened when Geoffrey Dean showed that astrologers are unable to predict whether someone is an introvert or an extrovert (an aspect that is very easy to determine through astrological study), how dare they claim to be able to predict more subtle aspects of the human personality? Others use the argument from authority to justify astrology. And what authority! According to the Astrology News Service , the Kryon spirit, ‘channeled’ by Lee Carroll, an entrepreneur with a sound engineering business who discovered the New Age in 1989, has recently said that “astrology is one of the least understood sciences.” For those who do not know him, Kryon is a half-angelic being who belongs to the Magnetic Service and is dedicated to adjusting the “electromagnetic grid of the Earth to facilitate the evolution of humanity”. With such support it is hard to understand why scientists are still reluctant to take astrology seriously…

The clearest proof of the arbitrariness of this pseudoscience is found in the supposed influences they have on us, Neptune and Pluto. Leaving aside the peculiar case of the latter, which astrologers included in their horoscopes because astronomers said it was a planet (what happens now that it isn’t? Why don’t they include the rest of the dwarf planets discovered in the recent years?), these augurs of the heavens have been able to assign a complete list of astrological properties to each of these planets despite the fact that Neptune completed its first orbit after its discovery in 2010 and Pluto has only traveled a sixth of its . The latter is funny: “astrologers say that Pluto is the astrological ruler of Scorpio even though, since its discovery, the planet has yet to enter that sign,” say Culver and Ianna. If astrology is an empirical science, how can they know what effect these planets have on each sign before they pass through them?


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