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Not to be confused with Astronomy.
Hey, baby! What's your sign?
The fault in our stars
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Adding epicycles
There are two ways to view the stars: as they really are; and as we might wish them to be.
Carl Sagan[1]

Astrology, sometimes called astromancy by its opponents, is an archaic pseudoscience that purports that the apparent position of the sun and planets relative to arbitrarily defined "star signs" at the time of your birth affect your personality and future.[2] It has somehow stood the test of time and has remained relatively popular.

According to the Faculty of Astrological Studies, astrology "explores the meaningful connection between mankind and the wider cosmos, the relationship between the movements of the planets and the inner world of human consciousness and motivation."[3] Some supporters like to emphasise that astrology is complex, and goes beyond just the simple "Sun Signs" people are used to[4] and others like to add amusing little rationales such as “Every human being contains every sign and every planet.”[5] Stripped of any fancier and woo-like terms, it is the belief that huge balls of rocks, liquids, gases, and nuclear fusion reactions billions or trillions of miles away from Earth can affect the financial, sexual, emotional, and employment situations of individual carbon-based life forms on one specific planet. Put like that, it sounds absurd, yet unlike many practitioners of alternative medicine who like to hide the absurdities behind complex terminology or assertions of mysterious energies, even fairly "advanced" astrology is still pretty open about the fact it's predicting the future based on staring into the sky.[6]

This widely believed idea has never produced any worthwhile and conclusive predictions, in spite of having several different formulations across disparate cultures. As far as astrology produces falsifiable predictions, it has been thoroughly falsified as no better than guesswork. As all the "evidence" that it is true is only anecdotal, selectively reported, or made up, it is an excellent example of a woo explanation for something quite mundane. To sum up, astrology can be described in a few words: the Forer effect in action.


A birth chart, as used by astrologers.

Because astrology is an ancient pseudoscience, its historical form can differ from the modern-day version. Indeed, there are many astrological traditions that vary from culture to culture, many associated with religions. Wide definitions of what constitutes astrology have been provided by historians and anthropologists. Patrick Curry defines astrology most broadly as:[7]

The practice of relating the heavenly bodies to lives and events on earth, and the tradition that has thus been generated.

Astrology today is the common computation and consultation system used by modern astrologers to explain personality types and factual events of today in terms of planetary movements and positions in their system. This is slightly more complicated than using birth month (which is used in horoscopes, as many people are familiar with), although it is no more accurate. Indeed, thanks to a few seasonal factors (see birth month, below) this may actually be less useful. However, it allows astrologers to sell personalised readings and give the impression that they've actually put some work into it.

Astrology's name[edit]

From astrology — Wiktionary, astronomy — Wiktionary, and the Liddell-Scott Lexicon, both words are derived from Classical Greek ones, astrologia and astronomia, and both words were used back then for discussions of celestial entities. It is only later that "astrology" got specialized to star divination and "astronomy" to star science. Its name thus looks much like the names of numerous reputable scientific and technical disciplines, names that end with -logy. A more appropriate name for astrology would be "astromancy", in analogy with the numerous forms of divination named with the suffix -mancy.


Astrological belief systems have existed for millennia and can be found all over the world. Early astrology often had a tight correlation with what is now called astronomy, and the line between the two was frequently quite blurry, if not completely non-existent. In fact, for a time, astronomy was known as "natural astrology".[citation needed] As such, a great deal of what we would call astronomy now was enmeshed with what we would call astrology. Astrology also made bedfellows with religion (celestial bodies often being compared or viewed as deities), a combination that is sometimes called astrotheology.

The earliest known form of astrology, Babylonian astrologyWikipedia, was present in Mesopotamia in the 2nd millenium BCE, where the stars were seen as revealing omens and the intentions of the gods. Evidence of astrology in the Olmec society also exists. Almost a millennium later, a form of astrology, likely influenced by the Babylonian sort, was developed in Egypt during the Hellenistic period. Hellenistic astrology, as it's called, was practiced for centuries, even after the Hellenistic period ended, and it remains one of the most influential forms of astrology to this day. Meanwhile, astrological systems were also developed in China during the Han Dynasty, in India during the Vedic period, and in numerous Mesoamerican civilizations across history. Judaism has had a long history of wrestling with astrology, with many differing opinions. Medieval Islamic astrology was in many ways a continuation of Hellenistic astrology influenced by various traditions. Later, astrology took flight in Renaissance Europe. While astrology fell out of favor during the Enlightenment, where around that time astrology and astronomy began to split off from each other in the Western world,[citation needed] the revival of spritualism led to a renewed interest in it. In the 1920s, Carl Jung developed theories that later became the foundation for psychological astrology (a.k.a. astropsychology). The presence of horoscopes in newspapers popularized astrology in the modern era greatly, and the New Age era has brought astrology to its current place in society.

Astrology as correlative cosmology[edit]

Professor Steve Farmer has argued[8] that several premodern belief systems may reasonably be described as "correlative cosmologies", belief systems that associate members of various sets of entities and events with each other, like celestial and terrestrial ones. He notes that in the West, they reached their height in the Renaissance, but soon went into decline. He describes his paper, coauthored with John B. Henderson and Michael Witzel, as "The first published paper to seriously link neurobiology and the evolution of religious and philosophical traditions, in a cross-cultural study of so-called correlative systems (in China), bandhus or upanishads (in India), and systems of correspondence (in the West)."

Astrology is an obvious example of a correlative cosmology. Astrology is based on correlations of celestial and terrestrial entities and events. Some of these have been worked out in incredibly gory detail by various astrologers. Renaissance Astrology has a collection of some writings of medieval and early-modern Western astrologers like al-Biruni and William Lilly, writings where one can find some of these correlations. Looking elsewhere, the medieval Western doctrine of signaturesWikipedia states that medicinal plants resemble parts of the body that they most useful for. Thus, liverwort got its name because its resemblance to livers suggested that it would be good for liver diseases. Meanwhile, in China, the WuxingWikipedia was developed. It is variously described as the Five Elements, the Five Phases, the Five Agents, the Five Movements, the Five Processes, and the Five Stages. It is a correspondence of sets of five materials, elements, planets, cardinal directions, colors, shapes, seasons, etc. Astrology is thus the main survivor of a lost world of woo-woo.

The single grain of reality[edit]

Movement of the vernal equinox across the years

A person's sign is supposed to be whichever constellation the Sun was in when they were born. However, it almost never is; only if your birthday is near the end of a specific range might that constellation actually be right. There are two reasons that the typical dates are inaccurate.

  1. Constellations vary in size: each sign occupies the dates for a thirty-degree range along the ecliptic, the path the sign appears to travel. This is at odds with reality, where each constellation has a different size and is never exactly 30° along the ecliptic. It means that constellations that barely touch the ecliptic, like Scorpio, get a 30-day range just because they happen to lie on one of the 30° increments. It also results in Ophiuchus, which is larger than and takes up almost twice as much space on the ecliptic as Scorpio, getting completely skipped. (This is, of course, ignoring the fact that constellations are defined arbitrarily by means of tradition, not any physical boundaries, and the boundaries currently in use were published by the IAU in 1930.)
  2. Earth's axis precesses: the typical dates have stayed exactly the same over thousands of years, even though the seasons and solstices have been gradually shifting over that time. The end result is that, while the Sun might have been in Capricorn during the beginning of January in the past, January has since moved to start when the Sun is in Sagittarius.

The actual dates[edit]

Since it's still fun to pretend, you might want to know what your actual arbitrary constellation is. Using the IAU-defined constellation boundaries, the current dates are:[9]

Constellation Usual dates Actual dates
Aries ♈︎ 21 March – 20 April 19 April – 13 May (25 days)
Taurus ♉︎ 21 April – 21 May 14 May – 19 June (37 days)
Gemini ♊︎ 22 May – 21 June 20 June – 20 July (31 days)
Cancer ♋︎ 22 June – 22 July 21 July – 9 August (20 days)
Leo ♌︎ 23 July – 22 August 10 August – 15 September (37 days)
Virgo ♍︎ 23 August – 23 September 16 September – 30 October (45 days)
Libra ♎︎ 24 September – 23 October 31 October – 22 November (23 days)
Scorpio ♏︎ 24 October – 22 November 23 November – 29 November (7 days)
Ophiuchus ⛎ N/A 30 November – 17 December (18 days)
Sagittarius ♐︎ 23 November – 21 December 18 December – 18 January (32 days)
Capricorn ♑︎ 22 December – 20 January 19 January – 15 February (28 days)
Aquarius ♒︎ 21 January – 19 February 16 February – 11 March (24 days)
Pisces ♓︎ 20 February – 20 March 12 March – 18 April (38 days)

Note that the dates for Libra and Scorpio do not overlap at all; anyone who thinks they are one of those is definitely something else.

When defending this discrepancy, astrologers claim that signs and constellations are two different things. Indeed, the modern tropical zodiac was created by taking the equinoxes and solstices and corresponding them to the four "cardinal" signs, and finding the rest of the signs by dividing the four seasons into three signs each for a grand total of 12. The modern Western zodiac has little to do with the constellations its 12 signs are named after, and more to do with the sun's cycle between the Tropic of Cancer and the Tropic of Capricorn.[note 1] It's not technically astrology, it's season-ology.

Another argument commonly used by astrologers is the idea that it goes deeper than your sun sign. The problem is that by this logic, the whole birth chart itself is still an extension of the Forer effect, since it still describes extremely similar personalities for many people around the world. It also becomes so vague to the point where you could just randomly describe someone by their Mercury sign or whatever. This idea also breaks down when a set of twins is brought into play. When using astrology logic, all twins around the world have exactly the same personality between each other. It's obvious that this is not the case.

Sidereal astrology[edit]

That being said, Vedic Astrology is sidereal, meaning that is based on where the constellations are now rather than where they were in antiquity the way Western or tropical astrology is. They still, however, do not use Ophiuchus. Because again, this stuff is arbitrary.

The scientific point of view[edit]

The scientific view, in the most candid form, is that astrology is a load of ancient nonsense that is, these days, perpetrated by ignorant fools or those wishing to exploit others. It is, for lack of a better word, crap. In the interest of being factual, honest, and accurate rather than merely rhetorical, the scientific point of view will be spread out in more detail below, but it will come to the same conclusion: astrology is crap.

Potential forces[edit]

Some of the celestial objects that supposedly rule our lives as seen through the Hubble Space Telescope

Fundamentally, astrology is the assertion that stuff happening in space affects us here — astrologers may suggest that it allows for predictions, but such predictions would not be possible if a connection did not somehow exist. This section explores whether such forces could exist. Astrologers may claim straw man here, but if there was a theoretically possible way to determine future events (or dictate personality types), there would be some connection whether they like it or not.

There is no known mechanism whereby a person could be significantly influenced by distant celestial bodies. A psychological explanation - where pretty shapes in the sky sub-consciously alter people's moods, perceptions or desires, like an accidental form of advertising or brainwashing — is unlikely as stars and celestial objects don't tend to be visible during the day and, with the exception of very dramatic events such as eclipses, all look the same to the untrained eye. In addition, viewing the stars (in order to be psychologically influenced by them) isn't a prerequisite for astrology, as a predictive mechanism, working.

More "physical" explanations are equally unlikely — this requires briefly looking into the physics that could possibly be behind it. The fundamental natural forces in nature are the strong and weak nuclear forces, the electromagnetic force, and the gravitational force. The strong and weak forces are nuclear forces, and are not applicable to interactions between people and objects such as planets or stars — their strengths tail off so dramatically with distance that they barely have any effect outside the nucleus of an atom, let alone at the macroscopic scale. Similarly, the electrostatic force — while acting at greater distances than nuclear forces — becomes completely negligible at modest distance, and does not act in any way over astronomical distance.

This leaves us with the one remaining "long-distance" force, gravity. However, despite working over far vaster distances than other forces, it is still practically impossible for planets to influence actions on Earth. Gravity follows the inverse square law, that is, that gravitational strength is proportional to the inverse of the square of the distance. As distance increases, gravitational pull decreases very dramatically; something that moves to twice as far away exerts a quarter of the gravitational pull, something three times further away exerts a ninth of the gravitational pull. Newton's law of gravitation can be used to show that, at its closest approach to Earth, the planet Mars exerts approximately the same gravitational force on a person as a 50-ton fully-loaded big rig placed 15 yards from that same person. The star Alpha Centauri A has a mass of 1.1 solar masses and is one of the three stars closest to Earth, yet its gravitational pull on a person is comparable to that of a 100-gram cellphone at 9 meters. The moon and sun, being closer, exert more force on the earth and result in the changing of tides (although this system is a little more complex than "the moon pulls water towards it"). Astrology is often not limited to just these two objects with the highest degree of gravitational interference and even so, these should — like with water in the tides — affect everyone equally.[10] It's fair to say, for an average newborn baby, that every person and piece of medical equipment in the delivery room has a much stronger gravitational influence than any of the stars or planets.

The great distances of these objects produce a further problem. Their pull on us is very close to their pull on the Earth as a whole. This differential pull is the tidal force, and it goes as the inverse cube of the distance. Not surprisingly, tidal forces are even smaller than overall gravitational ones. The planet Mars produces as much tidal effect on us as a small sand grain (diameter: 0.1 millimeters) at 1 yard or meter, and Alpha Centauri as much as a small virus (diameter: 30 nanometers) at that distance.

Astrological forces, furthermore, are allegedly powerful enough that they cannot be escaped by shielding or descent underground. It is possible to evade electromagnetic radiation of all kinds. Although it is possible to protect oneself from electromagnetic radiation (radio waves, infrared and ultraviolet radiation, visible light, X-rays) and ionizing radiation by shielding or going underground, astrological 'forces' supposedly can pass through lead-lined shielding or several meters of rock or hundreds of meters of water — the latter not creating its own astrological effects. Going into a mine, tunnel, cave, or submarine in an effort to avoid 'unfavorable' influences in one's horoscope gives one no protection (not that mines, tunnels, caves, and submarines are without their own dangers).

Whatever the mysterious force may be that astrologists claim causes the effects of the positions and movements of celestial bodies on human physiology, it is not backed up by any current knowledge or research and certainly isn't real. If there is a force, it can't be detected, and woo pushers tend to like that sort of thing — but this raises an important question; if it can't be detected in any way, shape or form, then how can it actually affect anything? However, we can still be open to so-called "supernatural" explanations and only look at the efficacy of astrology, treating it as a purely empirical question.

Birth month and other natural correlations[edit]

I don't believe in astrology; I'm a Sagittarius and we're skeptical.
Arthur C. Clarke

One force that almost certainly has an effect on people is the month they were born — though this has nothing to do with sun or star signs. Research at the Queensland University of Technology showed that in the Australian Football League (AFL) there were 33% more players born in January and 25% fewer in December.[11] A sign that the solar cycles can affect your sports playing ability? Not at all; it's simply a case of when the Australian school year begins. Those born in January are nearly 12 months older than peers born in the following December but are placed in the same school year, and the older ones are at a significant advantage at sports. When replicated in other countries with different distributions for the school year, the months where this trend appears shift accordingly.[12] This at least highlights some of the (very naturalistic) effects that need to be controlled for when assessing things like astrology; it is almost trivial to guess some trends but misread what causes them. In this case, the relative age effect is shown to have a cultural and location dependence, which would not be consistent with astrological predictions based on stars. The complexities involved in seasonal cycles of weather patterns, sunspots, and food production mean that time and date almost certainly correlate with a multitude of factors that can appear as very real trends. The development of astrology may have been tapping into these observations, but then overextended the effect to things that were just plain wrong. What is certain, however, is that attributing these simple correlations to quasi-magical forces and star signs is wrong.[13]

Testing of predictive value[edit]

Assuming astrology does work, then we should be able to get a reliable definition of what "astrology works" means. In this case, it should provide a reliable source of accurate predictions and statements, and these should be better than randomly guessing once naturalistic explanations for any successes (or in less politically correct terms, cheating) has been controlled for. This is an important aspect of testing astrology, as practitioners are highly likely to worm out of such conditions.[14] The American Federation of Astrologers suggest that astrology is "all in the timing",[15] which can be read as a tacit admission that a prediction that happens to be wrong was just badly timed, and therefore shouldn't count. One of the great successes of woo movements is convincing people that it's legitimate to ignore such misses and to think that a technique works except for the times that it doesn't. As a very good "technique works except for the times that it doesn't" is perfectly naturalistic guesswork, then holding up astrology to this standard is a perfectly valid way — indeed, it is the valid way — of testing its veracity.

Simple tests of horoscopes can be made by cutting out the predictions and scrambling what signs they refer to — or perhaps asking astrologers and/or amateurs to match the description with the sign. As people happily read what they like into statements as vague as horoscopes, this never ends in astrology's favour.[16] A test titled "A Scientific Inquiry into the Validity of Astrology"[17] had this to say in its abstract, demonstrating a fairly easy test protocol that should differentiate astrology being reliable and being bullshit:

Six expert astrologers independently attempted to match 23 astrological birth charts to the corresponding case files of 4 male and 19 female volunteers. Case files contained information on the volunteers' life histories, full-face and profile photographs, and test profiles from the Strong-Campbell Vocational Interest Blank and the Cattell 16-P.F. Personality Inventory. Astrologers did no better than chance or than a nonastrologer control subject at matching the birth charts to the personal data; this result was independent of astrologers' confidence ratings for their predicted matches. Astrologers also failed to agree with one another's predictions.

While astrologers and believers may accuse science of being quite dogmatic over the "astrology is bullshit" line, rest assured it has been tested. If astrology was anywhere near as potent a tool as believers and astrologers suggest, results from even small-scale tests should end positively. One of the more famous and better-controlled studies is the one performed by Shawn Carlson and published in Nature in 1985.[18][19] Here astrology was "given every reasonable chance to succeed", according to the author, but it failed. Astrologers were given the task of matching birth charts to personality types — a fairly simple task for a discipline that claims that your birth chart is "as unique as you are" and "reveals your potential in this lifetime and also where you are in that journey". Indeed, what would those phrases even mean if such a task couldn't be performed by an expert astrologer? However, astrologers themselves weren't best pleased with such a negative result, citing various issues with the apparently simple test. An article in the Astrology News Service is a curious example of kettle logicWikipedia as it seems to simultaneously assert that the test was unfair and skewed, and so unlikely to show any effect, and that reanalysis of the data suggests the astrologers were correct.[20]

Francesco Sizzi on Jupiter's Moons[edit]

At the beginning of 1610, Galileo Galilei looked at Jupiter with his telescope. The planet was resolved as a disk, and it had three faint stars nearby. A day or so later, he looked again, and the stars had moved. He continued to observe the planet, and he noticed that these three stars, and a fourth one also, were moving back and forth relative to Jupiter. He concluded that here were four objects that orbit Jupiter. The next year, a certain Francesco Sizzi of Florence made an astrological sort of argument that those moons cannot possibly exist. He wrote Dianoia astronomica, optica, physica, qua Syderei Nuncij rumor de quatuor planetis à Galilaeo Galilaeo mathematico celeberrimo recens perspicillì cuiusdam ope conspectis, vanus redditur. Auctore Francisco Sitio Florentino (in Latin; lpetrich's translation of its title: "Understanding of astronomy, optics, and physics, about a rumor in Sidereus Nuncius about the four planets seen by the very celebrated mathematician Galileo Galilei with his telescope, shown to be unfounded.") Here is his main argument (book page 16). In the macrocosm, there are seven planets: two favorable (beneficas) ones, two unfavorable (maleficas) ones, two luminaries, and unique Mercury, erratic and indifferent (vagum & indifferens). In the microcosm, the human head has seven openings: two nostrils, two eyes, two ears, and one mouth. He also noted that there are seven days in the week, seven metals, etc. Given all these corresponding sets of seven, there was clearly no place for the extra planets that Galileo had claimed to have discovered. So they do not exist.

Conversely one has to wonder why astrologers did not discover the existence of Uranus, Neptune, and Pluto -among other Solar System bodies not known to the developers of astrology- based on how their predictions were messed by the influences of several unknown bodies, before astronomers discovered them.[note 2]

There's something wrong with constellations[edit]

This is what happens to a constellation when you go to another star.

And not just that the resemblance between them and what they are said to represent is very debatable in most cases. Except on a few as OrionWikipedia, Ursa MajorWikipedia, or ScorpiusWikipedia, where some of the brightest stars that form a constellation are physically associated and at relatively similar distances to us[note 3], typically said stars are at very different separations from Earth and appear to form a pattern just from our vantage point.[note 4] In addition to this, as stars -the Sun included- orbit through the Milky Way said patterns change in a scale of many thousands of years becoming distinct with time.[note 5]

In addition to that, not only the twelve zodiacal constellations are the ones that are visited by the Sun, the Moon, and the planets (OphiuchusWikipedia is the best example, having been left out by the Babylonians as they had a twelve-month lunar calendar) but if one includes others the (western) Zodiac would have up to twenty-fiveWikipedia ones.[note 6]


Apart from Pluto, astrology does not take into account the dwarf planets - yet their gravity does have small perturbative effects on the orbits of other planets and the sun itself.

Predictions made by astrologers vary wildly from the vague to the specific — though most often they are extremely vague or at least vaguely in line with what most people think based on looking at the world around them, rather than the sky above. For instance, one prediction suggests "With Neptune in Pisces until 2024, we’ll see issues coming up in politics around water. There will be more flooding than ever before, unexpected hurricanes, tornadoes, typhoons and storms and towns and cities will disappear in the twinkling of an eye"[21] — which most climatologists suggest may well occur due to global warming. Indeed, other items mentioned in that prediction include "more products using nanotechnology", as if the increased use of a scientific buzzword was somehow only predictable through reading the stars and "expect to see huge growth in digital information clouds. At some point we’ll be able to stream all our music, TV, movies and books through subscription services. We’ll start to connect in new ways and we’ll know much more about each other" is bordering on self parody.

Generally, the more vague a prediction, the higher the chance it has of coming true. More accurately, the higher the chance that it can be interpreted as having been true after the fact, or retroactively reinterpreted as having not occurred because of some good graces. This can be seen most easily in the form of astrology that most people are familiar with; the horoscope. A horoscope is a prediction or advice based only on someone's date of birth, or more commonly (in newspapers and magazines, for instance) their zodiac sign, of which there are 12. Given that there are more than 6 billion people on Earth, at least one horoscope in every publication applies to more than 500 million people from the pigeonhole principle.[note 7] This gives more than enough room for even specific predictions to come true for a large number of people purely by accident. It is a clear fact that half a billion people do not have the same experiences each day, so the power of these predictions cannot be as widely and universally applied as is claimed.

Forer effect[edit]

See the main article on this topic: Forer effect

The Forer effect is where an over-generalised reading can be interpreted as very accurate by many people simultaneously. Often, Forer-type readings are very flattering or complimentary, but they can also mention hidden criticisms and insecurities that people realise they experience, but might not attribute to others and certainly like to hide. Therefore, by including statements like "you try to be bold, but worry about what other people might think of your actions and hesitate" you can give the impression you really did figure out new knowledge.

While astrologers often present birth charts as a deeper, more focused alternative to simple sun sign horoscopes, they actually make the Forer effect even vaguer by allowing contradictions. If you are a Capricorn (an introverted sign) but you have a Leo moon (very extroverted), you can relate to one or the other depending on whether you feel more extroverted or introverted. Mercury and Jupiter in opposite signs could make someone "an independent thinker who puts a lot of stock into others' opinions." People are incredibly complex, so throwing out more adjectives for every planet position will certainly make people think that their birth charts mean anything. If they disagree with any of the adjectives, the astrologer will (at best) simply say that a certain aspect of their chart causes them to differ, or (at worst) gaslight the victim into agreeing, possibly even encouraging highly social Taureans to cut ties with the majority of their friends – because some balls of gas wanted you to keep your circle small.

James Randi once replicated an experiment to demonstrate how people can basically be "tricked" into thinking a horoscope is accurate. A number of students were asked their zodiac and given the appropriate horoscope to read. They were then asked to grade how accurate they felt the horoscope was regarding their selves and a significant number, if not the majority, gave their horoscopes scores ranging from 4 to 5 (the maximum). Later they were asked to pass along their personal horoscope to the person behind them where the "trick" was revealed; they had all been given the same horoscope.[note 8] This is a demonstration of the Forer effect and how the language used in horoscopes can be vague and widely applicable to many people yet still give the illusion of being very specific. With a careful selection of language, phrases and tone, it is almost impossible for a horoscope to not to be applicable to someone.[22]

Value to science[edit]

Like many protosciences, astrology provided the original foundation of a modern science, in its case astronomy. As scientists started trying to understand what the bright things we see in the sky are, where they are, and their relationship to each other, astrology was able to provide some thousands of years of observations to develop hypotheses from. After all, mystics spent so much time gazing at the sky that it was inevitable some useful information would slip into human knowledge.

To a lesser extent, horoscopes - which would include fairly accurate astronomical data - of figures in the past and clear mentions of what were then "astrological" events may help modern historians with efforts to assign accurate dates to the past.

Whatever you do, however, do NOT confuse astrology with astronomy when talking to an astronomer—you will be soundly rebutted and possibly insulted.

Social consequences of astrology beliefs[edit]

Job advertisements in China have been known to discriminate against certain star-signs. If you are a Scorpio, good luck finding a job there – and that's not even getting into Chinese astrology. We wish we were making this up.[23]

Prominent critical theorist Theodor Adorno criticized astrology, and particularly what was found in the astrological columns of the LA Times, as "pseudo-rationality" that promoted complacency in his essay "The Stars Down to Earth":

What drives people into the arms of the various kinds of “prophets of deceit” is not only their sense of dependence and their wish to attribute this dependence to some “higher” and ultimately more justifiable sources, but it is also their wish to reinforce their own dependence, not to have to take matters into their own hands - a wish, true, which is ultimately engendered by the pressure under which they live... This is pretty well reflected by astrology as well by the two brands of totalitarian states which also claim to have a key for everything, know all the answers, reduce the complex to simple and mechanical inferences, doing away with anything that is strange and unknown and at the same time fail to explain anything.[24]

Age of Aquarius[edit]

The earth rotates on an axis tilted about 23.4° in position to the sun; the exact direction of the tilt slowly rotates over time, and it takes about 26,000 years to complete one round. This is called Axial precessionWikipedia. Astrologers maintain that there are twelve 2,160 year "ages", one for each sign of the zodiac (26,000 ÷ 12 = 2,160).

According to the astrologers, the change from one age to the other can cause the rise and fall of civilizations, cultural changes, and all sorts of shit. There is disagreement among astrologers over whether this "age" has already started, or is forthcoming.

For example David Williams claimed that the Age of Aquarius started in 1844 and attributes the rise of socialism, communism, and fascism to it[25] and Marcia Moore & Mark Douglas credit the American Revolution, the Industrial Revolution, and the discovery of electricity to it.[26] There are about as many variants as astrologers, as it's all simply asserted with no empirical evidence.

Some of them interoperated astrology and 2012 apocalypse theories and claimed that Age of Aquarius would occur in 2012, leading to all sorts of spectacular good shit such as free energy and "spiritual growth".[27][28] Well, it seems they were as wrong as the doomsayers...

The age of Aquarius was further cemented in pop culture by being sung about in the 1967 musical HairWikipedia, which was also covered and became a radio hitWikipedia.

Quote mining[edit]

What utter madness in these astrologers, in considering the effect of the vast, slow movements and change in the heavens, to assume that wind and rain have no effect at birth!
—Marcus Tullius Cicero, 44 B.C.E
I don't know how many of you people believe in astrology.... (Girl in audience: You're a Sagittarius!) Yes that's right, that's right baby... (I love you.) I'm a Sagittarius. (I know. I read up on you....) The most philosophical of all the signs. (So am I.) But anyway, I don't believe in it. (I don't either) I think it's a bunch of bullshit, myself. But I tell you this man...I don't know what's gonna happen, man, but I'm gonna have my kicks before all the whole shithouse goes up in flames.
—Jim Morrison
Now you may find it inconceivable or at the very least a bit unlikely that the relative position of the planets and the stars could have a special deep significance or meaning that exclusively applies to only you, but let me give you my assurance that these forecasts and predictions are all based on solid scientific documented evidence, so you would have to be some kind of moron not to realize that every single one of them is absolutely true. Where was I?
—"Weird Al" Yankovic, "Your Horoscope For Today"[29]
Astronomy is an exact science... Astrology is superstition.
Patrick Moore
I don't believe in astrology. The only stars I can blame for my failures are those that walk about the stage.
—Noel Coward
Jupiter's passed through Orion
And coming to conjunction with Mars
Saturn is wheeling through infinite space
To its pre-ordained place in the stars
And I gaze at the planets in wonder
At the trouble and time they expend
Just to warn me to be careful
In dealings involving a friend
—Flanders and Swann, "My Horoscope"[30]

One last thing[edit]

Round and round and round they go. Where they stop, nobody knows.

One clever thing astrologers have done is make each zodiac sign have a flaw that could lead to not believing in astrology.[31]

Our resident astrologer has this to say about your flaws:

  • Aquarius: Stubborn, and would hold on to their opinion of astrology.
  • Pisces: Takes on other people's problems, and would thus meddle in someone's belief in astrology.
  • Aries: Dismissive, and would thus dismiss astrology without knowing much about it.
  • Taurus: Cautious, and would thus be too careful in adopting a new belief.
  • Gemini: Poor Listeners, and would thus just shut out information on astrology.
  • Cancer: Moody, and would let this get ahead of the "logic" of astrology.
  • Leo: Vain, and would deny that such a system exists, as they must be perfect.
  • Virgo: Overly logical, and would refuse astrology for, well, the complete lack of logic in deciding stars decide your personality.
  • Libra: Indecisive, and would be unable to decide on astrology.
  • Scorpio: Hostile, and would not accept this new information if it was brought up by someone they disliked.
  • Sagittarius: Unpredictable, and would not accept this "True" information for god knows why.
  • Capricorn: Judgemental, and would not accept this hippie belief.

The problem with all of this is that it gives astrologers an easy way to get out of an argument about astrology's legitimacy — "Oh, of course you don't believe! You're a _________, and they are __________."

See also[edit]

Want to read this in another language?[edit]

Русскоязычным вариантом данной статьи является статья Астрология

External links[edit]

Completely bullshit external links[edit]

None of these links are endorsed by RationalWiki but are presented (for your amusement only) as examples of the genre.


  1. Can you guess how the tropics got their names?
  2. Note that Neptune was at first indirectly discoveredWikipedia due to the perturbations it caused on Uranus' orbit
  3. Of the examples given, note that just Scorpius is typically considered zodiacal. Note also that "relatively similar" still means differences in distances of up to hundreds of light-years between their brighest ones
  4. You can see how such patterns change and become unrecognizable as seen from another star (it's also fun to go to another star and see how our Sun would appear from there), even nearby ones, using the open source program CelestiaWikipedia. With StellariumWikipedia, also open source, you can see too how the night sky changes as millennia go by due to the effects of precession and even stars moving due to their motions around the galactic center.
  5. This without including in a few cases the effects of stellar evolution (ask Betelgeuse)
  6. If you use modern constellation boundaries, things that did not exist back in the day
  7. Barring any birth timing irregularities, on average every horoscope should be applicable to around 500 million people.
  8. Astrological scammers sometimes give a very basic reading that's likely to be true for most people. They offer more detailed readings for a fee, spamming then goes on and on.


  1. A Personal Voyage — Harmony of the Worlds
  2. According to Dr. Sheldon Cooper
  3. Faculty of Astrological Studies - Why study astrology?
  4. Cafe Astrology — What is astrology?
  5. Astrology Energy
  6. American Federation of Astrologers — AFA Advanced Course in Relationships
  8. Steve Farmer, Neurobiology, layered texts, and correlative cosmologies: A cross-cultural framework for premodern history.
  9. The Real Constellations of the Zodiac, Dr. Lee T. Shapiro
  10. Scientific American — Lunacy and the Full Moon
  11. Science Daily — Month of Birth Determines Who Becomes a Sports Star
  12. BBC News — How to build a champion: Be born at the right time
  13. Nature News — Astrology's Myopia
  14. The Double-Blind Astrology Experiment — see comments on this blog entry, for example.]
  15. American Federation of Astrologers — main page
  16. Paranormal Encylopedia — Astrology Experiment (spoiler alert; it just presents you with the standard Forer test. Like you didn't see that one coming, right?)
  17. Journal Scientific Exploration. Vol. 4, No. I, pp. 75-83, 1990 (PDF file)
  18. A double-blind test of astrology, Nature 318, 419 - 425
  19. Skeptical Studies in Astrology
  20. Astrology News Service - Support for Astrology from the Carlson Double-Blind Experiment
  21. Astrological Predictions 2012-2013, Barbara Goldsmith
  22. YouTube: James Randi on Astrology
  23. China Job Ads Discriminate Against Scorpio and Virgo, The Telegraph
  25. David Williams, Simplified Astronomy for Astrologers, 1969, American Federation of Astrologers, pp. 45–56
  26. Marcia Moore & Mark Douglas, Astrology, The Divine Science, 1971, p. 677