Astrological beliefs in correspondences between celestial observations and terrestrial events have influenced various aspects of human history, including world-views, language and many elements of social culture.
Among Indo-European peoples, astrology has been dated to the 3rd millennium BC, with roots in calendrical systems used to predict seasonal shifts and to interpret celestial cycles as signs of divine communications. Until the 17th century, astrology was considered a scholarly tradition, and it helped drive the development of astronomy. It was commonly accepted in political and cultural circles, and some of its concepts were used in other traditional studies, such as alchemy, meteorology and medicine. By the end of the 17th century, emerging scientific concepts in astronomy, such as heliocentrism, were irrevocably undermining the theoretical basis of astrology, which subsequently lost its academic standing.
In the 20th century, astrology gained broader consumer popularity through the influence of regular mass media products, such as newspaper horoscopes.
Astrology, in its broadest sense, is the search for human meaning in the sky; it seeks to understand general and specific human behavior through the influence of planets and other celestial objects. It has been argued that astrology began as a study as soon as human beings made conscious attempts to measure, record, and predict seasonal changes by reference to astronomical cycles.
Early evidence of such practices appears as markings on bones and cave walls, which show that lunar cycles were being noted as early as 25,000 years ago; the first step towards recording the Moon’s influence upon tides and rivers, and towards organizing a communal calendar. With the Neolithic agricultural revolution new needs were also met by increasing knowledge of constellations, whose appearances in the night-time sky change with the seasons, allowing the rising of particular star-groups to herald annual floods or seasonal activities. By the 3rd millennium BC, widespread civilisations had developed sophisticated awareness of celestial cycles, and are believed to have consciously oriented their temples to create alignment with the heliacal risings of the stars.
There is scattered evidence to suggest that the oldest known astrological references are copies of texts made during this period, particularly in Mesopotamia (Sumer, Akkad, Assyria and Babylonia). Two, from the Venus tablet of Ammisaduqa (compiled in Babylon round 1700 BC) are reported to have been made during the reign of king Sargon of Akkad (2334-2279 BC). Another, showing an early use of electional astrology, is ascribed to the reign of the Sumerian ruler Gudea of Lagash (c. 2144 - 2124 BC). This describes how the gods revealed to him in a dream the constellations that would be most favourable for the planned construction of a temple. However, controversy attends the question of whether they were genuinely recorded at the time or merely ascribed to ancient rulers by posterity. The oldest undisputed evidence of the use of astrology as an integrated system of knowledge is therefore attributed to the records that emerge from the first dynasty of Mesopotamia (1950-1651 BC).
Babylonian astrology was the first organized system of astrology, arising in the 2nd millennium BC. There is speculation that astrology of some form appeared in the Sumerian period in the 3rd millennium BC, but the isolated references to ancient celestial omens dated to this period are not considered sufficient evidence to demonstrate an integrated theory of astrology. The history of scholarly celestial divination is therefore generally reported to begin with late Old Babylonian texts (c. 1800 BC), continuing through the Middle Babylonian and Middle Assyrian periods (c. 1200 BC).
By the 16th century BC the extensive employment of omen-based astrology can be evidenced in the compilation of a comprehensive reference work known as Enuma Anu Enlil. Its contents consisted of 70 cuneiform tablets comprising 7,000 celestial omens. Texts from this time also refer to an oral tradition - the origin and content of which can only be speculated upon. At this time Babylonian astrology was solely mundane, concerned with the prediction of weather and political matters, and prior to the 7th century BC the practitioners' understanding of astronomy was fairly rudimentary. Astrological symbols likely represented seasonal tasks, and were used as a yearly almanac of listed activities to remind a community to do things appropriate to the season or weather (such as symbols representing times for harvesting, gathering shell-fish, fishing by net or line, sowing crops, collecting or managing water reserves, hunting, and seasonal tasks critical in ensuring the survival of children and young animals for the larger group). By the 4th century, their mathematical methods had progressed enough to calculate future planetary positions with reasonable accuracy, at which point extensive ephemerides began to appear.
Babylonian astrology developed within the context of divination. A collection of 32 tablets with inscribed liver models, dating from about 1875 BC, are the oldest known detailed texts of Babylonian divination, and these demonstrate the same interpretational format as that employed in celestial omen analysis. Blemishes and marks found on the liver of the sacrificial animal were interpreted as symbolic signs which presented messages from the gods to the king.
The gods were also believed to present themselves in the celestial images of the planets or stars with whom they were associated. Evil celestial omens attached to any particular planet were therefore seen as indications of dissatisfaction or disturbance of the god that planet represented. Such indications were met with attempts to appease the god and find manageable ways by which the god’s expression could be realised without significant harm to the king and his nation. An astronomical report to the king Esarhaddon concerning a lunar eclipse of January 673 BC shows how the ritualistic use of substitute kings, or substitute events, combined an unquestioning belief in magic and omens with a purely mechanical view that the astrological event must have some kind of correlate within the natural world:
... In the beginning of the year a flood will come and break the dikes. When the Moon has made the eclipse, the king, my lord, should write to me. As a substitute for the king, I will cut through a dike, here in Babylonia, in the middle of the night. No one will know about it.
Ulla Koch-Westenholz, in her 1995 book Mesopotamian Astrology, argues that this ambivalence between a theistic and mechanic worldview defines the Babylonian concept of celestial divination as one which, despite its heavy reliance on magic, remains free of implications of targeted punishment with the purpose of revenge, and so “shares some of the defining traits of modern science: it is objective and value-free, it operates according to known rules, and its data are considered universally valid and can be looked up in written tabulations”. Koch-Westenholz also establishes the most important distinction between ancient Babylonian astrology and other divinatory disciplines as being that the former was originally exclusively concerned with mundane astrology, being geographically oriented and specifically applied to countries cities and nations, and almost wholly concerned with the welfare of the state and the king as the governing head of the nation.Mundane astrology is therefore known to be one of the oldest branches of astrology. It was only with the gradual emergence of horoscopic astrology, from the 6th century BC, that astrology developed the techniques and practice of natal astrology.
Main article: Hellenistic astrology
In 525 BC Egypt was conquered by the Persians so there is likely to have been some Mesopotamian influence on Egyptian astrology. Arguing in favour of this, historian Tamsyn Barton gives an example of what appears to be Mesopotamian influence on the Egyptian zodiac, which shared two signs – the Balance and the Scorpion, as evidenced in the Dendera Zodiac (in the Greek version the Balance was known as the Scorpion’s Claws).
After the occupation by Alexander the Great in 332 BC, Egypt came under Hellenistic rule and influence. The city of Alexandria was founded by Alexander after the conquest and during the 3rd and 2nd centuries BC, the scholars of Alexandria were prolific writers. It was in Ptolemaic Alexandria that Babylonian astrology was mixed with the Egyptian tradition of Decanic astrology to create Horoscopic astrology. This contained the Babylonian zodiac with its system of planetary exaltations, the triplicities of the signs and the importance of eclipses. Along with this it incorporated the Egyptian concept of dividing the zodiac into thirty-six decans of ten degrees each, with an emphasis on the rising decan, the Greek system of planetary Gods, sign rulership and four elements.
The decans were a system of time measurement according to the constellations. They were led by the constellation Sothis or Sirius. The risings of the decans in the night were used to divide the night into ‘hours’. The rising of a constellation just before sunrise (its heliacal rising) was considered the last hour of the night. Over the course of the year, each constellation rose just before sunrise for ten days. When they became part of the astrology of the Hellenistic Age, each decan was associated with ten degrees of the zodiac. Texts from the 2nd century BC list predictions relating to the positions of planets in zodiac signs at the time of the rising of certain decans, particularly Sothis. The earliest Zodiac found in Egypt dates to the 1st century BC, the Dendera Zodiac.
Particularly important in the development of horoscopic astrology was the astrologer and astronomer Ptolemy, who lived in Alexandria in Egypt. Ptolemy's work the Tetrabiblos laid the basis of the Western astrological tradition, and as a source of later reference is said to have "enjoyed almost the authority of a Bible among the astrological writers of a thousand years or more". It was one of the first astrological texts to be circulated in Medieval  Europe after being translated from Arabic into Latin by Plato of Tivoli (Tiburtinus) in Spain, 1138.
According to Firmicus Maternus (4th century), the system of horoscopic astrology was given early on to an Egyptian pharaoh named Nechepso and his priest Petosiris. The Hermetic texts were also put together during this period and Clement of Alexandria, writing in the Roman era, demonstrates the degree to which astrologers were expected to have knowledge of the texts in his description of Egyptian sacred rites:
This is principally shown by their sacred ceremonial. For first advances the Singer, bearing some one of the symbols of music. For they say that he must learn two of the books of Hermes, the one of which contains the hymns of the gods, the second the regulations for the king's life. And after the Singer advances the Astrologer, with a horologe in his hand, and a palm, the symbols of astrology. He must have the astrological books of Hermes, which are four in number, always in his mouth.
Greece and Rome
The conquest of Asia by Alexander the Great exposed the Greeks to the cultures and cosmological ideas of Syria, Babylon, Persia and central Asia. Greek overtook cuneiform script as the international language of intellectual communication and part of this process was the transmission of astrology from cuneiform to Greek. Sometime around 280 BC, Berossus, a priest of Bel from Babylon, moved to the Greek island of Kos in order to teach astrology and Babylonian culture to the Greeks. With this, what historican Nicholas Campion calls, "the innovative energy" in astrology moved west to the Hellenistic world of Greece and Egypt. According to Campion, the astrology that arrived from the Eastern World was marked by its complexity, with different forms of astrology emerging. By the 1st century BC two varieties of astrology were in existence, one that required the reading of horoscopes in order to establish precise details about the past, present and future; the other being theurgic (literally meaning 'god-work'), which emphasised the soul's ascent to the stars. While they were not mutually exclusive, the former sought information about the life, while the latter was concerned with personal transformation, where astrology served as a form of dialogue with the Divine.
As with much else, Greek influence played a crucial role in the transmission of astrological theory to Rome. However, our earliest references to demonstrate its arrival in Rome reveal its initial influence upon the lower orders of society, and display concern about uncritical recourse to the ideas of Babylonian 'star-gazers'. Among the Greeks and Romans, Babylonia (also known as Chaldea) became so identified with astrology that 'Chaldean wisdom' came to be a common synonym for divination using planets and stars.
The first definite reference to astrology comes from the work of the orator Cato, who in 160 BC composed a treatise warning farm overseers against consulting with Chaldeans. The 2nd-century Roman poet Juvenal, in his satirical attack on the habits of Roman women, also complains about the pervasive influence of Chaldeans, despite their lowly social status, saying "Still more trusted are the Chaldaeans; every word uttered by the astrologer they will believe has come from Hammon's fountain, ... nowadays no astrologer has credit unless he has been imprisoned in some distant camp, with chains clanking on either arm".
One of the first astrologers to bring Hermetic astrology to Rome was Thrasyllus, who, in the first century CE, acted as the astrologer for the emperorTiberius. Tiberius was the first emperor reported to have had a court astrologer, although his predecessor Augustus had also used astrology to help legitimise his Imperial rights. In the second century CE, the astrologer Claudius Ptolemy was so obsessed with getting horoscopes accurate that he began the first attempt to make an accurate world map (maps before this were more relativistic or allegorical) so that he could chart the relationship between the person's birthplace and the heavenly bodies. While doing so, he coined the term "geography".
Even though some use of astrology by the emperors appears to have happened, there was also a prohibition on astrology to a certain extent as well. In the 1st century CE, Publius Rufus Anteius was accused of the crime of funding the banished astrologer Pammenes, and requesting his own horoscope and that of then emperor Nero. For this crime, Nero forced Anteius to commit suicide. At this time, astrology was likely to result in charges of magic and treason.
A Latin translation of Abū Maʿshar's De Magnis Coniunctionibus ("Of the great conjunctions"), Venice, 1515.
|Native name||Abū Maʿshar, Jaʿfar ibn Muḥammad al-Balkhī|
|Era||Islamic Golden Age|
|Main interests||Astrology, Astronomy|
|Influenced||Al-Sijzi, Albertus Magnus, Roger Bacon, Pierre d'Ailly, Pico della Mirandola.|
Further information: Astrology in medieval Islam
Astrology was taken up enthusiastically by Islamic scholars following the collapse of Alexandria to the Arabs in the 7th century, and the founding of the Abbasid empire in the 8th century. The second Abbasid caliph, Al Mansur (754-775) founded the city of Baghdad to act as a centre of learning, and included in its design a library-translation centre known as Bayt al-Hikma ‘Storehouse of Wisdom’, which continued to receive development from his heirs and was to provide a major impetus for Arabic translations of Hellenistic astrological texts. The early translators included Mashallah, who helped to elect the time for the foundation of Baghdad, and Sahl ibn Bishr (a.k.a. Zael), whose texts were directly influential upon later European astrologers such as Guido Bonatti in the 13th century, and William Lilly in the 17th century. Knowledge of Arabic texts started to become imported into Europe during the Latin translations of the 12th century.
Amongst the important names of Arabic astrologers, one of the most influential was Albumasur, whose work Introductorium in Astronomiam later became a popular treatise in medieval Europe. Another was the Persian mathematician, astronomer, astrologer and geographer Al Khwarizmi. The Arabs greatly increased the knowledge of astronomy, and many of the star names that are commonly known today, such as Aldebaran, Altair, Betelgeuse, Rigel and Vega retain the legacy of their language. They also developed the list of Hellenistic lots to the extent that they became historically known as Arabic parts, for which reason it is often wrongly claimed that the Arabic astrologers invented their use, whereas they are clearly known to have been an important feature of Hellenistic astrology.
During the advance of Islamic science some of the practices of astrology were refuted on theological grounds by astronomers such as Al-Farabi (Alpharabius), Ibn al-Haytham (Alhazen) and Avicenna. Their criticisms argued that the methods of astrologers were conjectural rather than empirical, and conflicted with orthodox religious views of Islamic scholars through the suggestion that the Will of God can be precisely known and predicted in advance. Such refutations mainly concerned 'judicial branches' (such as horary astrology), rather than the more 'natural branches' such as medical and meteorological astrology, these being seen as part of the natural sciences of the time.
For example, Avicenna’s 'Refutation against astrology' Resāla fī ebṭāl aḥkām al-nojūm, argues against the practice of astrology while supporting the principle of planets acting as the agents of divine causation which express God's absolute power over creation. Avicenna considered that the movement of the planets influenced life on earth in a deterministic way, but argued against the capability of determining the exact influence of the stars. In essence, Avicenna did not refute the essential dogma of astrology, but denied our ability to understand it to the extent that precise and fatalistic predictions could be made from it.
Medieval and Renaissance Europe
Further information: Renaissance magic
Whilst astrology in the East flourished following the break up of the Roman world, with Indian, Persian and Islamic influences coming together and undergoing intellectual review through an active investment in translation projects, Western astrology in the same period had become “fragmented and unsophisticated ... partly due to the loss of Greek scientific astronomy and partly due to condemnations by the Church.” Translations of Arabic works into Latin started to make their way to Spain by the late 10th century, and in the 12th century the transmission of astrological works from Arabia to Europe “acquired great impetus”.
By the 13th century astrology had become a part of everyday medical practice in Europe. Doctors combined Galenic medicine (inherited from the Greek physiologist Galen - AD 129-216) with studies of the stars. By the end of the 1500s, physicians across Europe were required by law to calculate the position of the Moon before carrying out complicated medical procedures, such as surgery or bleeding.
Influential works of the 13th century include those of the British monk Johannes de Sacrobosco (c. 1195–1256) and the Italian astrologer Guido Bonatti from Forlì (Italy). Bonatti served the communal governments of Florence, Siena and Forlì and acted as advisor to Frederick II, Holy Roman Emperor. His astrological text-book Liber Astronomiae ('Book of Astronomy'), written around 1277, was reputed to be "the most important astrological work produced in Latin in the 13th century".Dante Alighieri immortalised Bonatti in his Divine Comedy (early 14th century) by placing him in the eighth Circle of Hell, a place where those who would divine the future are forced to have their heads turned around (to look backwards instead of forwards).
In medieval Europe, a university education was divided into seven distinct areas, each represented by a particular planet and known as the seven liberal arts. Dante attributed these arts to the planets. As the arts were seen as operating in ascending order, so were the planets in decreasing order of planetary speed: grammar was assigned to the Moon, the quickest moving celestial body, dialectic was assigned to Mercury, rhetoric to Venus, music to the Sun, arithmetic to Mars, geometry to Jupiter and astrology/astronomy to the slowest moving body, Saturn.
Medieval writers used astrological symbolism in their literary themes. For example, Dante's Divine Comedy builds varied references to planetary associations within his described architecture of Hell, Purgatory and Paradise, (such as the seven layers of Purgatory's mountain purging the seven cardinal sins that correspond to astrology's seven classical planets). Similar astrological allegories and planetary themes are pursued through the works of Geoffrey Chaucer.
Chaucer's astrological passages are particularly frequent and knowledge of astrological basics is often assumed through his work. He knew enough of his period's astrology and astronomy to write a Treatise on the Astrolabe for his son. He pinpoints the early spring season of the Canterbury Tales in the opening verses of the prologue by noting that the Sun "hath in the Ram his halfe cours yronne". He makes the Wife of Bath refer to "sturdy hardiness" as an attribute of Mars, and associates Mercury with "clerkes". In the early modern period, astrological references are also to be found in the works of William Shakespeare and John Milton.
One of the earliest English astrologers to leave details of his practice was Richard Trewythian (b. 1393). His notebook demonstrates that he had a wide range of clients, from all walks of life, and indicates that engagement with astrology in 15th-century England was not confined to those within learned, theological or political circles.
During the Renaissance, court astrologers would complement their use of horoscopes with astronomical observations and discoveries. Many individuals now credited with having overturned the old astrological order, such as Tycho Brahe, Galileo Galilei and Johannes Kepler, were themselves practicing astrologers.
At the end of the Renaissance the confidence placed in astrology diminished, with the breakdown of Aristotelian Physics and rejection of the distinction between the celestial and sublunar realms, which had historically acted as the foundation of astrological theory. Keith Thomas writes that although heliocentrism is consistent with astrology theory, 16th and 17th century astronomical advances meant that "the world could no longer be envisaged as a compact inter-locking organism; it was now a mechanism of infinite dimensions, from which the hierarchical subordination of earth to heaven had irrefutably disappeared". Initially, amongst the astronomers of the time, "scarcely anyone attempted a serious refutation in the light of the new principles" and in fact astronomers "were reluctant to give up the emotional satisfaction provided by a coherent and interrelated universe". By the 18th century the intellectual investment which had previously maintained astrology's standing was largely abandoned. Historian of science Ann Geneva writes:
Astrology in seventeenth century England was not a science. It was not a Religion. It was not magic. Nor was it astronomy, mathematics, puritanism, neo Platism, psychology, meteorology, alchemy or witchcraft. It used some of these as tools; it held tenets in common with others; and some people were adept at several of these skills. But in the final analysis it was only itself: a unique divinatory and prognostic art embodying centuries of accreted methodology and tradition.
Main articles: Indian astronomy and Hindu astrology
The earliest use of the term jyotiṣa is in the sense of a Vedanga, an auxiliary discipline of Vedic religion. The only work of this class to have survived is the Vedanga Jyotisha, which contains rules for tracking the motions of the sun and the moon in the context of a five-year intercalation cycle. The date of this work is uncertain, as its late style of language and composition, consistent with the last centuries BC, albeit pre-Mauryan, conflicts with some internal evidence of a much earlier date in the 2nd millennium BC.
The documented history of Jyotish in the subsequent newer sense of modern horoscopic astrology is associated with the interaction of Indian and Hellenistic cultures in the Indo-Greek period. Greek became a lingua franca of the Indus valley region following the military conquests of Alexander the Great and the Bactrian Greeks. The oldest surviving treatises, such as the Yavanajataka or the Brihat-Samhita, date to the early centuries AD. The oldest astrological treatise in Sanskrit is the Yavanajataka ("Sayings of the Greeks"), a versification by Sphujidhvaja in 269/270 AD of a now lost translation of a Greek treatise by Yavanesvara during the 2nd century AD under the patronage of the Western SatrapSaka king Rudradaman I.
Indian astronomy and astrology developed together. The earliest treatise on jyotish, the Bhrigu Samhita, dates from the Vedic era. The sage Bhrigu is one of the Saptarshi, the seven sages who assisted in the creation of the universe. Written on pages of tree bark, the Samhita (Compilation) is said to contain five million horoscopes comprising all who have lived in the past or will live in the future. The first named authors writing treatises on astronomy are from the 5th century AD, the date when the classical period of Indian astronomy can be said to begin. Besides the theories of Aryabhata in the Aryabhatiya and the lost Arya-siddhānta, there is the Pancha-Siddhāntika of Varahamihira.
Main article: Chinese astrology
Chinese system is based on astronomy and calendars and its significant development is tied to that of astronomy, which came to flourish during the Han Dynasty (2nd century BC to 2nd century AD).
Chinese astrology has a close relation with Chinese philosophy (theory of the three harmony, heaven, earth and water) and uses the principles of yin and yang and concepts that are not found in Western astrology, such as the wu xing teachings, the 10 Celestial stems, the 12 Earthly Branches, the lunisolar calendar (moon calendar and sun calendar), and the time calculation after year, month, day and shichen (時辰).
Astrology was traditionally regarded highly in China, and Confucius is said to have treated astrology with respect saying: "Heaven sends down its good or evil symbols and wise men act accordingly". The 60-year cycle combining the five elements with the twelve animal signs of the zodiac has been documented in China since at least the time of the Shang (Shing or Yin) dynasty (ca 1766 BC – ca 1050 BC). Oracles bones have been found dating from that period with the date according to the 60-year cycle inscribed on them, along with the name of the diviner and the topic being divined about. One of the most famous astrologers in China was Tsou Yen who lived in around 300 BC, and who wrote: "When some new dynasty is going to arise, heaven exhibits auspicious signs for the people".
Main articles: Maya calendar and Aztec calendar
The calendars of Pre-Columbian Mesoamerica are based upon a system which had been in common use throughout the region, dating back to at least the 6th century BC. The earliest calendars were employed by peoples such as the Zapotecs and Olmecs, and later by such peoples as the Maya, Mixtec and Aztecs. Although the Mesoamerican calendar did not originate with the Maya, their subsequent extensions and refinements to it were the most sophisticated. Along with those of the Aztecs, the Maya calendars are the best-documented and most completely understood.
The distinctive Mayan calendar used two main systems, one plotting the solar year of 360 days, which governed the planting of crops and other domestic matters; the other called the Tzolkin of 260 days, which governed ritual use. Each was linked to an elaborate astrological system to cover every facet of life. On the fifth day after the birth of a boy, the Mayan astrologer-priests would cast his horoscope to see what his profession was to be: soldier, priest, civil servant or sacrificial victim. A 584-day Venus cycle was also maintained, which tracked the appearance and conjunctions of Venus. Venus was seen as a generally inauspicious and baleful influence, and Mayan rulers often planned the beginning of warfare to coincide with when Venus rose. There is evidence that the Maya also tracked the movements of Mercury, Mars and Jupiter, and possessed a zodiac of some kind. The Mayan name for the constellation Scorpio was also 'scorpion', while the name of the constellation Gemini was 'peccary'. There is some evidence for other constellations being named after various beasts. The most famous Mayan astrological observatory still intact is the Caracol observatory in the ancient Mayan city of Chichen Itza in modern-day Mexico.
The Aztec calendar shares the same basic structure as the Mayan calendar, with two main cycles of 360 days and 260 days. The 260-day calendar was called Tonalpohualli and was used primarily for divinatory purposes. Like the Mayan calendar, these two cycles formed a 52-year 'century', sometimes called the Calendar Round.
- ^Koch-Westenholz (1995) Foreword and p.11.
- ^Kassell and Ralley (2010) ‘Stars, spirits, signs: towards a history of astrology 1100–1800'; pp.67–69.
- ^Campion (2009) pp.259–263, for the popularizing influence of newspaper astrology; pp. 239–249: for association with New Age philosophies.
- ^Campion (2008) pp.1-3.
- ^Marshack (1972) p.81ff.
- ^Hesiod (c. 8th century BC). Hesiod’s poem Works and Days demonstrates how the heliacal rising and setting of constellations were used as a calendrical guide to agricultural events, from which were drawn mundane astrological predictions, e.g.: “Fifty days after the solstice, when the season of wearisome heat is come to an end, is the right time to go sailing. Then you will not wreck your ship, nor will the sea destroy the sailors, unless Poseidon the Earth-Shaker be set upon it, or Zeus, the king of the deathless gods” (II. 663-677).
- ^Kelley and Milone (2005) p.268.
- ^Two texts which refer to the 'omens of Sargon' are reported in E. F. Weidner, ‘Historiches Material in der Babyonischen Omina-Literatur’ Altorientalische Studien, ed. Bruno Meissner, (Leipzig, 1928-9), v. 231 and 236.
- ^From scroll A of the ruler Gudea of Lagash, I 17 – VI 13. O. Kaiser, Texte aus der Umwelt des Alten Testaments, Bd. 2, 1-3. Gütersloh, 1986-1991. Also quoted in A. Falkenstein, ‘Wahrsagung in der sumerischen Überlieferung’, La divination en Mésopotamie ancienne et dans les régions voisines. Paris, 1966.
- ^Rochberg-Halton, F. (1988). "Elements of the Babylonian Contribution to Hellenistic Astrology". Journal of the American Oriental Society. 108 (1): 51–62. doi:10.2307/603245. JSTOR 603245.
- ^Holden (1996) p.1.
- ^Rochberg (1998) p.ix. See also, Neugebauer (1969)pp.29-30.
- ^Rochberg (1998) p.x.
- ^Baigent (1994) p.71.
- ^Holden (1996) p.9.
- ^Koch-Westenholz (1995) p.16.
- ^Koch-Westenholz (1995) p.11.
- ^Koch-Westenholz (1995) p.12. Tablet source given as: State Archives of Assyria 8 250.
- ^Koch-Westenholz (1995) p.13.
- ^Koch-Westenholz (1995) p.19.
- ^Michael Baigent (1994). From the Omens of Babylon: Astrology and Ancient Mesopotamia. Arkana.
- ^Michael Baigent, Nicholas Campion and Charles Harvey (1984). Mundane astrology. Thorsons.
- ^Steven Vanden Broecke (2003). The limits of influence: Pico, Louvain, and the crisis of Renaissance astrology. BRILL. pp. 185–. ISBN 978-90-04-13169-9. Retrieved 5 April 2012.
- ^Barton (1994) p. 24.
- ^Holden (1996) pp. 11-13.
- ^Barton (1994) p. 20.
- ^Robbins, Ptolemy Tetrabiblos, 'Introduction' p. xii.
- ^"The History of Astrology". Retrieved 2016-12-28.
- ^FA Robbins, 1940; Thorndike 1923)
- ^Firmicus (4th century) (III.4) 'Proemium'.
- ^Roberts (1906)p.488.
- ^Campion (2008) p. 173.
- ^Campion (2008) p. 84.
- ^Campion (2008) pp.173-174.
- ^ abcBarton (1994) p.32.
- ^Campion (2008) pp.227-228.
- ^Parkers (1983) p.16.
- ^Barton (1994) p.32-33. See also Campion (2008) pp.228.
- ^Juvenal, Satire 6: 'The Ways of Women' (translated by G. G. Ramsay, 1918, retrieved 5 July 2012).
- ^Barton (1994) p.43.
- ^Barton (1994) p.63.
- ^Thompson, Clive. "The Whole World in your Hands". Smithsonian, July 2017. p. 19.
- ^Rudich, Vasily (2005). Political Dissidence Under Nero: The Price of Dissimulation. Routledge. pp. 145–146. ISBN 9781134914517. Retrieved 2015-01-03.
- ^Houlding (2010) Ch. 8: 'The medieval development of Hellenistic principles concerning aspectual applications and orbs'; pp.12-13.
- ^Albiruni, Chronology (11th century) Ch.VIII, ‘On the days of the Greek calendar’, re. 23 Tammûz; Sachau.
- ^Houlding (2010) Ch. 6: 'Historical sources and traditional approaches'; pp.2-7.
- ^"Introduction to Astronomy, Containing the Eight Divided Books of Abu Ma'shar Abalachus". World Digital Library. 1506. Retrieved 2013-07-16.
- ^Saliba (1994) p.60, pp.67-69.
- ^Belo (2007) p.228.
- ^George Saliba, Avicenna: 'viii. Mathematics and Physical Sciences'. Encyclopaedia Iranica, Online Edition, 2011, available at http://www.iranicaonline.org/articles/avicenna-viii
- ^ abNick Kanas, Star Maps: History, Artistry, and Cartography, p.79 (Springer, 2007).
- ^British Library: Learning Bodies of Knowledge ‘Medieval Astrology’ https://web.archive.org/web/20130305064820/http://www.bl.uk/learning/artimages/bodies/astrology/astrologyhome.html (25 Octobre 2016)
- ^Lewis, James R. (2003). The Astrology Book. Body, Mind & Spirit.
- ^Alighieri, Dante (1867). Divine Comedy. Ticknor and Fields.
- ^Burckhardt (1969)
- ^Crane (2012) pp.81-85.
- ^A. Kitson (1996). "Astrology and English literature". Contemporary Review, Oct 1996. Retrieved 2006-07-17. M. Allen, J.H. Fisher. "Essential Chaucer: Science, including astrology". University of Texas, San Antonio. Retrieved 2006-07-17. A.B.P. Mattar; et al. "Astronomy and Astrology in the Works of Chaucer"(PDF). University of Singapore. Retrieved 2006-07-17.
Since the 2008 financial crisis, colleges and universities have faced increased pressure to identify essential disciplines, and cut the rest. In 2009, Washington State University announced it would eliminate the department of theatre and dance, the department of community and rural sociology, and the German major – the same year that the University of Louisiana at Lafayette ended its philosophy major. In 2012, Emory University in Atlanta did away with the visual arts department and its journalism programme. The cutbacks aren’t restricted to the humanities: in 2011, the state of Texas announced it would eliminate nearly half of its public undergraduate physics programmes. Even when there’s no downsizing, faculty salaries have been frozen and departmental budgets have shrunk.
But despite the funding crunch, it’s a bull market for academic economists. According to a 2015 sociological studyin the Journal of Economic Perspectives, the median salary of economics teachers in 2012 increased to $103,000 – nearly $30,000 more than sociologists. For the top 10 per cent of economists, that figure jumps to $160,000, higher than the next most lucrative academic discipline – engineering. These figures, stress the study’s authors, do not include other sources of income such as consulting fees for banks and hedge funds, which, as many learned from the documentary Inside Job (2010), are often substantial. (Ben Bernanke, a former academic economist and ex-chairman of the Federal Reserve, earns $200,000-$400,000 for a single appearance.)
Unlike engineers and chemists, economists cannot point to concrete objects – cell phones, plastic – to justify the high valuation of their discipline. Nor, in the case of financial economics and macroeconomics, can they point to the predictive power of their theories. Hedge funds employ cutting-edge economists who command princely fees, but routinely underperform index funds. Eight years ago, Warren Buffet made a 10-year, $1 million bet that a portfolio of hedge funds would lose to the S&P 500, and it looks like he’s going to collect. In 1998, a fund that boasted two Nobel Laureates as advisors collapsed, nearly causing a global financial crisis.
The failure of the field to predict the 2008 crisis has also been well-documented. In 2003, for example, only five years before the Great Recession, the Nobel Laureate Robert E Lucas Jr told the American Economic Association that ‘macroeconomics […] has succeeded: its central problem of depression prevention has been solved’. Short-term predictions fair little better – in April 2014, for instance, a survey of 67 economists yielded 100 per cent consensus: interest rates would rise over the next six months. Instead, they fell. A lot.
Nonetheless, surveys indicate that economists see their discipline as ‘the most scientific of the social sciences’. What is the basis of this collective faith, shared by universities, presidents and billionaires? Shouldn’t successful and powerful people be the first to spot the exaggerated worth of a discipline, and the least likely to pay for it?
In the hypothetical worlds of rational markets, where much of economic theory is set, perhaps. But real-world history tells a different story, of mathematical models masquerading as science and a public eager to buy them, mistaking elegant equations for empirical accuracy.
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As an extreme example, take the extraordinary success of Evangeline Adams, a turn-of-the-20th-century astrologer whose clients included the president of Prudential Insurance, two presidents of the New York Stock Exchange, the steel magnate Charles M Schwab, and the banker J P Morgan. To understand why titans of finance would consult Adams about the market, it is essential to recall that astrology used to be a technical discipline, requiring reams of astronomical data and mastery of specialised mathematical formulas. ‘An astrologer’ is, in fact, the Oxford English Dictionary’s second definition of ‘mathematician’. For centuries, mapping stars was the job of mathematicians, a job motivated and funded by the widespread belief that star-maps were good guides to earthly affairs. The best astrology required the best astronomy, and the best astronomy was done by mathematicians – exactly the kind of person whose authority might appeal to bankers and financiers.
In fact, when Adams was arrested in 1914 for violating a New York law against astrology, it was mathematics that eventually exonerated her. During the trial, her lawyer Clark L Jordan emphasised mathematics in order to distinguish his client’s practice from superstition, calling astrology ‘a mathematical or exact science’. Adams herself demonstrated this ‘scientific’ method by reading the astrological chart of the judge’s son. The judge was impressed: the plaintiff, he observed, went through a ‘mathematical process to get at her conclusions… I am satisfied that the element of fraud… is absent here.’
Romer compares debates among economists to those between 16th-century advocates of heliocentrism and geocentrism
The enchanting force of mathematics blinded the judge – and Adams’s prestigious clients – to the fact that astrology relies upon a highly unscientific premise, that the position of stars predicts personality traits and human affairs such as the economy. It is this enchanting force that explains the enduring popularity of financial astrology, even today. The historian Caley Horan at the Massachusetts Institute of Technology described to me how computing technology made financial astrology explode in the 1970s and ’80s. ‘Within the world of finance, there’s always a superstitious, quasi-spiritual trend to find meaning in markets,’ said Horan. ‘Technical analysts at big banks, they’re trying to find patterns in past market behaviour, so it’s not a leap for them to go to astrology.’ In 2000, USA Today quoted Robin Griffiths, the chief technical analyst at HSBC, the world’s third largest bank, saying that ‘most astrology stuff doesn’t check out, but some of it does’.
Ultimately, the problem isn’t with worshipping models of the stars, but rather with uncritical worship of the language used to model them, and nowhere is this more prevalent than in economics. The economist Paul Romer at New York University has recently begun calling attention to an issue he dubs ‘mathiness’ – first in the paper ‘Mathiness in the Theory of Economic Growth’ (2015) and then in a series of blog posts. Romer believes that macroeconomics, plagued by mathiness, is failing to progress as a true science should, and compares debates among economists to those between 16th-century advocates of heliocentrism and geocentrism. Mathematics, he acknowledges, can help economists to clarify their thinking and reasoning. But the ubiquity of mathematical theory in economics also has serious downsides: it creates a high barrier to entry for those who want to participate in the professional dialogue, and makes checking someone’s work excessively laborious. Worst of all, it imbues economic theory with unearned empirical authority.
‘I’ve come to the position that there should be a stronger bias against the use of math,’ Romer explained to me. ‘If somebody came and said: “Look, I have this Earth-changing insight about economics, but the only way I can express it is by making use of the quirks of the Latin language”, we’d say go to hell, unless they could convince us it was really essential. The burden of proof is on them.’
Right now, however, there is widespread bias in favour of using mathematics. The success of math-heavy disciplines such as physics and chemistry has granted mathematical formulas with decisive authoritative force. Lord Kelvin, the 19th-century mathematical physicist, expressed this quantitative obsession:
When you can measure what you are speaking about and express it in numbers you know something about it; but when you cannot measure it… in numbers, your knowledge is of a meagre and unsatisfactory kind.
The trouble with Kelvin’s statement is that measurement and mathematics do not guarantee the status of science – they guarantee only the semblance of science. When the presumptions or conclusions of a scientific theory are absurd or simply false, the theory ought to be questioned and, eventually, rejected. The discipline of economics, however, is presently so blinkered by the talismanic authority of mathematics that theories go overvalued and unchecked.
Romer is not the first to elaborate the mathiness critique. In 1886, an article in Science accused economics of misusing the language of the physical sciences to conceal ‘emptiness behind a breastwork of mathematical formulas’. More recently, Deirdre N McCloskey’s The Rhetoric of Economics (1998) and Robert H Nelson’s Economics as Religion (2001) both argued that mathematics in economic theory serves, in McCloskey’s words, primarily to deliver the message ‘Look at how very scientific I am.’
After the Great Recession, the failure of economic science to protect our economy was once again impossible to ignore. In 2009, the Nobel Laureate Paul Krugman tried to explain it in The New York Times with a version of the mathiness diagnosis. ‘As I see it,’ he wrote, ‘the economics profession went astray because economists, as a group, mistook beauty, clad in impressive-looking mathematics, for truth.’ Krugman named economists’ ‘desire… to show off their mathematical prowess’ as the ‘central cause of the profession’s failure’.
The mathiness critique isn’t limited to macroeconomics. In 2014, the Stanford financial economist Paul Pfleiderer published the paper ‘Chameleons: The Misuse of Theoretical Models in Finance and Economics’, which helped to inspire Romer’s understanding of mathiness. Pfleiderer called attention to the prevalence of ‘chameleons’ – economic models ‘with dubious connections to the real world’ that substitute ‘mathematical elegance’ for empirical accuracy. Like Romer, Pfleiderer wants economists to be transparent about this sleight of hand. ‘Modelling,’ he told me, ‘is now elevated to the point where things have validity just because you can come up with a model.’
The notion that an entire culture – not just a few eccentric financiers – could be bewitched by empty, extravagant theories might seem absurd. How could all those people, all that math, be mistaken? This was my own feeling as I began investigating mathiness and the shaky foundations of modern economic science. Yet, as a scholar of Chinese religion, it struck me that I’d seen this kind of mistake before, in ancient Chinese attitudes towards the astral sciences. Back then, governments invested incredible amounts of money in mathematical models of the stars. To evaluate those models, government officials had to rely on a small cadre of experts who actually understood the mathematics – experts riven by ideological differences, who couldn’t even agree on how to test their models. And, of course, despite collective faith that these models would improve the fate of the Chinese people, they did not.
Astral Science in Early Imperial China, a forthcoming book by the historian Daniel P Morgan, shows that in ancient China, as in the Western world, the most valuable type of mathematics was devoted to the realm of divinity – to the sky, in their case (and to the market, in ours). Just as astrology and mathematics were once synonymous in the West, the Chinese spoke of li, the science of calendrics, which early dictionaries also glossed as ‘calculation’, ‘numbers’ and ‘order’. Li models, like macroeconomic theories, were considered essential to good governance. In the classic Book of Documents, the legendary sage king Yao transfers the throne to his successor with mention of a single duty: ‘Yao said: “Oh thou, Shun! The li numbers of heaven rest in thy person.”’
China’s oldest mathematical text invokes astronomy and divine kingship in its very title – The Arithmetical Classic of the Gnomon of the Zhou. The title’s inclusion of ‘Zhou’ recalls the mythic Eden of the Western Zhou dynasty (1045–771 BCE), implying that paradise on Earth can be realised through proper calculation. The book’s introduction to the Pythagorean theorem asserts that ‘the methods used by Yu the Great in governing the world were derived from these numbers’. It was an unquestioned article of faith: the mathematical patterns that govern the stars also govern the world. Faith in a divine, invisible hand, made visible by mathematics. No wonder that a newly discovered text fragment from 200 BCE extolls the virtues of mathematics over the humanities. In it, a student asks his teacher whether he should spend more time learning speech or numbers. His teacher replies: ‘If my good sir cannot fathom both at once, then abandon speech and fathom numbers, [for] numbers can speak, [but] speech cannot number.’
Modern governments, universities and businesses underwrite the production of economic theory with huge amounts of capital. The same was true for li production in ancient China. The emperor – the ‘Son of Heaven’ – spent astronomical sums refining mathematical models of the stars. Take the armillary sphere, such as the two-metre cage of graduated bronze rings in Nanjing, made to represent the celestial sphere and used to visualise data in three-dimensions. As Morgan emphasises, the sphere was literally made of money. Bronze being the basis of the currency, governments were smelting cash by the metric ton to pour it into li. A divine, mathematical world-engine, built of cash, sanctifying the powers that be.
The enormous investment in li depended on a huge assumption: that good government, successful rituals and agricultural productivity all depended upon the accuracy of li. But there were, in fact, no practical advantages to the continued refinement of li models. The calendar rounded off decimal points such that the difference between two models, hotly contested in theory, didn’t matter to the final product. The work of selecting auspicious days for imperial ceremonies thus benefited only in appearance from mathematical rigour. And of course the comets, plagues and earthquakes that these ceremonies promised to avert kept on coming. Farmers, for their part, went about business as usual. Occasional governmental efforts to scientifically micromanage farm life in different climes using li ended in famine and mass migration.
Like many economic models today, li models were less important to practical affairs than their creators (and consumers) thought them to be. And, like today, only a few people could understand them. In 101 BCE, Emperor Wudi tasked high-level bureaucrats – including the Great Director of the Stars – with creating a new li that would glorify the beginning of his path to immortality. The bureaucrats refused the task because ‘they couldn’t do the math’, and recommended the emperor outsource it to experts.
The equivalent in economic theory might be to grant a model high points for success in predicting short-term markets, while failing to deduct for missing the Great Recession
The debates of these ancient li experts bear a striking resemblance to those of present-day economists. In 223 CE, a petition was submitted to the emperor asking him to approve tests of a new li model developed by the assistant director of the astronomical office, a man named Han Yi.
At the time of the petition, Han Yi’s model, and its competitor, the so-called Supernal Icon, had already been subjected to three years of ‘reference’, ‘comparison’ and ‘exchange’. Still, no one could agree which one was better. Nor, for that matter, was there any agreement on how they should be tested.
In the end, a live trial involving the prediction of eclipses and heliacal risings was used to settle the debate. With the benefit of hindsight, we can see this trial was seriously flawed. The helical rising (first visibility) of planets depends on non-mathematical factors such as eyesight and atmospheric conditions. That’s not to mention the scoring of the trial, which was modelled on archery competitions. Archers scored points for proximity to the bullseye, with no consideration for overall accuracy. The equivalent in economic theory might be to grant a model high points for success in predicting short-term markets, while failing to deduct for missing the Great Recession.
None of this is to say that li models were useless or inherently unscientific. For the most part, li experts were genuine mathematical virtuosos who valued the integrity of their discipline. Despite being based on inaccurate assumptions – that the Earth was at the centre of the cosmos – their models really did work to predict celestial motions. Imperfect though the live trial might have been, it indicates that superior predictive power was a theory’s most important virtue. All of this is consistent with real science, and Chinese astronomy progressed as a science, until it reached the limits imposed by its assumptions.
However, there was no science to the belief that accurate li would improve the outcome of rituals, agriculture or government policy. No science to the Hall of Light, a temple for the emperor built on the model of a magic square. There, by numeric ritual gesture, the Son of Heaven was thought to channel the invisible order of heaven for the prosperity of man. This was quasi-theology, the belief that heavenly patterns – mathematical patterns – could be used to model every event in the natural world, in politics, even the body. Macro- and microcosm were scaled reflections of one another, yin and yang in a unifying, salvific mathematical vision. The expensive gadgets, the personnel, the bureaucracy, the debates, the competition – all of this testified to the divinely authoritative power of mathematics. The result, then as now, was overvaluation of mathematical models based on unscientific exaggerations of their utility.
In ancient China it would have been unfair to blame li experts for the pseudoscientific exploitation of their theories. These men had no way to evaluate the scientific merits of assumptions and theories – ‘science’, in a formalised, post-Enlightenment sense, didn’t really exist. But today it is possible to distinguish, albeit roughly, science from pseudoscience, astronomy from astrology. Hypothetical theories, whether those of economists or conspiracists, aren’t inherently pseudoscientific. Conspiracy theories can be diverting – even instructive – flights of fancy. They become pseudoscience only when promoted from fiction to fact without sufficient evidence.
Romer believes that fellow economists know the truth about their discipline, but don’t want to admit it. ‘If you get people to lower their shield, they’ll tell you it’s a big game they’re playing,’ he told me. ‘They’ll say: “Paul, you may be right, but this makes us look really bad, and it’s going to make it hard for us to recruit young people.”’
Demanding more honesty seems reasonable, but it presumes that economists understand the tenuous relationship between mathematical models and scientific legitimacy. In fact, many assume the connection is obvious – just as in ancient China, the connection between li and the world was taken for granted. When reflecting in 1999 on what makes economics more scientific than the other social sciences, the Harvard economist Richard B Freeman explained that economics ‘attracts stronger students than [political science or sociology], and our courses are more mathematically demanding’. In Lives of the Laureates (2004), Robert E Lucas Jr writes rhapsodically about the importance of mathematics: ‘Economic theory is mathematical analysis. Everything else is just pictures and talk.’ Lucas’s veneration of mathematics leads him to adopt a method that can only be described as a subversion of empirical science:
The construction of theoretical models is our way to bring order to the way we think about the world, but the process necessarily involves ignoring some evidence or alternative theories – setting them aside. That can be hard to do – facts are facts – and sometimes my unconscious mind carries out the abstraction for me: I simply fail to see some of the data or some alternative theory.
Even for those who agree with Romer, conflict of interest still poses a problem. Why would skeptical astronomers question the emperor’s faith in their models? In a phone conversation, Daniel Hausman, a philosopher of economics at the University of Wisconsin, put it bluntly: ‘If you reject the power of theory, you demote economists from their thrones. They don’t want to become like sociologists.’
George F DeMartino, an economist and an ethicist at the University of Denver, frames the issue in economic terms. ‘The interest of the profession is in pursuing its analysis in a language that’s inaccessible to laypeople and even some economists,’ he explained to me. ‘What we’ve done is monopolise this kind of expertise, and we of all people know how that gives us power.’
Every economist I interviewed agreed that conflicts of interest were highly problematic for the scientific integrity of their field – but only tenured ones were willing to go on the record. ‘In economics and finance, if I’m trying to decide whether I’m going to write something favourable or unfavourable to bankers, well, if it’s favourable that might get me a dinner in Manhattan with movers and shakers,’ Pfleiderer said to me. ‘I’ve written articles that wouldn’t curry favour with bankers but I did that when I had tenure.’
when mathematical theory is the ultimate arbiter of truth, it becomes difficult to see the difference between science and pseudoscience
Then there’s the additional problem of sunk-cost bias. If you’ve invested in an armillary sphere, it’s painful to admit that it doesn’t perform as advertised. When confronted with their profession’s lack of predictive accuracy, some economists find it difficult to admit the truth. Easier, instead, to double down, like the economist John H Cochrane at the University of Chicago. The problem isn’t too much mathematics, he writes in response to Krugman’s 2009 post-Great-Recession mea culpa for the field, but rather ‘that we don’t have enough math’. Astrology doesn’t work, sure, but only because the armillary sphere isn’t big enough and the equations aren’t good enough.
If overhauling economics depended solely on economists, then mathiness, conflict of interest and sunk-cost bias could easily prove insurmountable. Fortunately, non-experts also participate in the market for economic theory. If people remain enchanted by PhDs and Nobel Prizes awarded for the production of complicated mathematical theories, those theories will remain valuable. If they become disenchanted, the value will drop.
Economists who rationalise their discipline’s value can be convincing, especially with prestige and mathiness on their side. But there’s no reason to keep believing them. The pejorative verb ‘rationalise’ itself warns of mathiness, reminding us that we often deceive each other by making prior convictions, biases and ideological positions look ‘rational’, a word that confuses truth with mathematical reasoning. To be rational is, simply, to think in ratios, like the ratios that govern the geometry of the stars. Yet when mathematical theory is the ultimate arbiter of truth, it becomes difficult to see the difference between science and pseudoscience. The result is people like the judge in Evangeline Adams’s trial, or the Son of Heaven in ancient China, who trust the mathematical exactitude of theories without considering their performance – that is, who confuse math with science, rationality with reality.
There is no longer any excuse for making the same mistake with economic theory. For more than a century, the public has been warned, and the way forward is clear. It’s time to stop wasting our money and recognise the high priests for what they really are: gifted social scientists who excel at producing mathematical explanations of economies, but who fail, like astrologers before them, at prophecy.
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Alan Jay Levinovitz
is an assistant professor of philosophy and religion at James Madison University in Virginia. His most recent book is The Gluten Lie: And Other Myths About What You Eat (2015).