Islamic & Arabic astrology

What Islamic and Arabic astrology is

Islamic or Arabic astrology is the astrology practised in Arabic, and in Persian, across the Islamic world from the 8th to the 14th century. Its practitioners were Muslims, Jews, Christians and Sabians, which is why historians often prefer "Arabic" for the language over "Islamic" for the faith. Its authors called it 'ilm ahkam al-nujum, the science of the judgments of the stars, and kept it apart from 'ilm al-hay'a, the mathematical astronomy that supplied its numbers. The astrologer, the munajjim, was a court official as much as a consultant. He cast nativities, but he also forecast the fortunes of dynasties, picked the hour for a campaign or a coronation, and answered questions put by viziers and merchants. The tradition did not simply preserve Greek astrology. It combined Greek geometry, Persian cycles of history and Indian mathematics into a single system, argued for it in the terms of Aristotle's physics, and sent the result on to Europe.

Baghdad: a city founded by the stars

The Abbasid dynasty took power in 750 and borrowed much of its idea of kingship from Sasanian Persia, including the Persian habit of reading royal power in the stars and of paying for scholarship. Its most famous astrological act was the founding of Baghdad. The caliph al-Mansur asked his astrologers Nawbakht, a Persian, and Masha'allah, a Jew from Basra, to elect the moment for the first bricks of his Round City, and they chose the afternoon of 31 July 762. In the chart as modern historians have reconstructed it, Sagittarius is rising and its ruler Jupiter, the greater benefic, sits in the first house, a promise of long and prosperous rule. Mars, the planet of war, is placed in the sixth house. The sixth is a weak, cadent house, which limits the damage Mars can do, and it is also the house of Mars's joy in the Hellenistic scheme, so the city would keep its martial strength without turning it on itself. Historians still argue over details, including whether the astrologers worked with a sidereal Persian zodiac rather than the tropical one.

The translation movement

Over the next two centuries Baghdad became the centre of an immense translation effort. Caliphs, especially al-Ma'mun, who reigned from 813 to 833, and wealthy families at court paid for Greek, Syriac, Persian and Sanskrit works to be put into Arabic. The library and academy tradition known as the Bayt al-Hikma, the House of Wisdom, stands for the whole enterprise. Ptolemy's Tetrabiblos became the Kitab al-Arba'a, the Book of the Four; the astrological poem of Dorotheus of Sidon arrived through a Persian version; Vettius Valens was known; and the Persian and Indian astronomical tables, the zij, gave astrologers the planetary positions they needed. The Sabians of Harran, a community that had kept the old star religion and Hermetic lore alive, played a large part. Their best-known scholar, Thabit ibn Qurra, read Greek, Syriac and Arabic and translated and corrected the mathematical works on which astrology depended.

Al-Kindi: astrology as physics

Hellenistic astrology came wrapped in Stoic fate, astral religion and Hermetic mysticism, all hard to reconcile with tawhid, the absolute oneness of God, and with a Creator who acts freely. Astrologers who wanted a place in Islamic intellectual life needed a natural mechanism, not a pantheon. The philosopher al-Kindi, who died around 873, supplied one. In On the Rays of the Stars, which survives in Latin as De radiis, he argued that every thing in the world sends out rays in all directions, and that the stars, being vast, eternal and made of the pure celestial substance, send the strongest and most ordered rays of all. These rays pass down into the world below the Moon and act as causes there, heating and cooling, moving and combining the four elements. Seen this way, astrology stopped being the interpretation of omens and became the study of a physical force acting across distance. The same idea of radiation shaped medieval optics and later the natural magic of European writers.

Abu Ma'shar and the Great Introduction

Abu Ma'shar of Balkh, who lived from 787 to 886, is the central figure of the tradition. Stories told by his pupil Shadhan say he began as a scholar of hadith and turned to astronomy and astrology only in middle age, after a quarrel with al-Kindi; he went on to become the most prolific and famous astrologer of his century, and some contemporaries, al-Biruni among them later, accused him of taking more from al-Kindi than he admitted. His Great Introduction to the Science of the Judgments of the Stars opens with a long defence of the art drawn from Aristotle's Physics and On Generation and Corruption. The eternal circular motion of the heavens, he argues, acts on the four elements, making them mix, heat, cool and separate. The positions of the planets, their aspects and their distances therefore shape the weather, living bodies and human affairs below. God remains the first cause who moves the outermost sphere; the planets are secondary causes, the gears through which His order reaches the earth. The argument answered the chief theological objection of the day. It also mattered far beyond astrology: the historian Richard Lemay showed that the Latin translations of the book, by John of Seville in 1133 and Hermann of Carinthia in 1140, were among the first texts that brought Aristotle's natural philosophy back to Western Europe, before Aristotle's own works arrived in Latin.

History written in the conjunctions

Hellenistic astrology was mainly about individual birth charts. The Arabic tradition, drawing on Sasanian Persian ideas about ages of the world, made mundane astrology, the astrology of nations, dynasties, religions and weather, into a large and systematic field. Abu Ma'shar's Book of Thousands adapted the enormous Indian and Persian cycles of world time to the history of the scriptures, placing a conjunction of all the planets at the beginning of Aries in 3102 BCE and dating the Flood by it. His Book of Conjunctions built the working method on Jupiter and Saturn, the two slowest planets visible to the eye. They meet roughly every twenty years, and each meeting falls about 243 degrees on from the last, which keeps a series of conjunctions within the three signs of one element for some 240 years before it shifts to the next. After about 960 years the series has passed through all four elements and returns to where it began. The astrologers read the three scales as three sizes of event:

• the single conjunction, every 20 years or so, for rebellions, local rulers and short-term disturbance;
• the shift of element, every 240 years or so, for new religious movements, the rise and ruin of states and changes of dynasty;
• the return to the first element, every 960 years or so, for the transfer of world power and the coming of prophets.

The scheme was used both backward and forward. Astrologers pointed out that the Prophet Muhammad was born in 571, soon after the conjunctions shifted into the water signs with a meeting in Scorpio, and they read later events of early Islam against the same cycle. Looking ahead, they searched the coming shifts for signs of the end of Abbasid rule, and later writers read the Mongol sack of Baghdad in 1258, when Hulagu Khan put the last Abbasid caliph to death, as a fulfilment of such warnings. The famous conjunction of all the planets in Libra in 1186, which set off a panic of end-time prophecies across Europe and the Middle East, shows how seriously the doctrine was taken.

Houses, instruments and exact time

The Hellenistic astrologers had mostly used whole-sign houses, in which each sign of the zodiac is one house counted from the rising sign. Astronomers in the Islamic world, trained in spherical trigonometry and required to fix the times of prayer and the direction of Mecca precisely, favoured quadrant systems that divide the sky from the observer's own horizon and meridian. The most widely used was the one taught by al-Qabisi, known in Latin as Alcabitius, whose Introduction to the Art of the Judgments of the Stars, written for the court of Sayf al-Dawla in Aleppo and translated by John of Seville, became the standard astrology textbook of medieval European universities. His method is based on time. It takes the diurnal semi-arc of the Ascendant degree, the time that degree needs to travel from the eastern horizon to the Midheaven, divides it into three equal parts, and carries the divisions back to the ecliptic along hour circles to find the cusps of the eleventh, twelfth, second and third houses. Doing this by hand needed trigonometric tables. The astrolabe made it quick: this brass instrument maps the sphere of the sky onto a flat plate by stereographic projection, and makers in Baghdad and later al-Andalus engraved house lines on the plates for a given latitude, so that turning the star map to the right hour showed the cusps at a glance.

The Lots, or Arabic Parts

A Lot is a point in a chart found by taking the distance between two points and measuring it again from the Ascendant. The Greeks had used a small set, most famously the seven Hermetic Lots listed by Paulus Alexandrinus. Arabic astrologers extended them to almost every subject of human life, and al-Biruni's Book of Instruction in the Elements of the Art of Astrology, written in 1029, lists them in detail. Europe knew them as the Arabic Parts. The best known are:

• the Lot of Fortune, Ascendant plus Moon minus Sun in a day chart, the lunar Lot of the body, health and material circumstance;
• the Lot of Spirit, Ascendant plus Sun minus Moon in a day chart, the solar Lot of will, action and vocation;
• the Lot of Wealth, Ascendant plus the cusp of the second house minus the ruler of the second, for property and possessions;
• the Lot of Death, Ascendant plus the cusp of the eighth house minus the Moon, for the themes of the eighth house, endings, losses and inheritance, read symbolically rather than as a date.

In a night chart the Sun and Moon swap places in the first two formulas. By turning a question into a point that can be located and watched, the Lots gave the munajjim a way to examine almost any matter separately, from a marriage to the outcome of an illness.

Dignities and the almuten

With so many planets, houses and Lots in play, astrologers needed a way to decide which factors carried the most weight. They formalised the essential dignities, the strength a planet draws from its sign through domicile, exaltation, triplicity, term and face, and added accidental dignities such as house position, speed and visibility. From these came the almuten, from the Arabic al-mubtazz, the victor. The astrologer scores each planet's dignity over the key points of the chart, usually the Ascendant, the Sun, the Moon, the Lot of Fortune and the new or full Moon before birth, and the planet with the highest total is the almuten of the whole nativity, taken as its governing influence and an important guide to length of life. Masha'allah and Abu Ma'shar used such methods, and Guido Bonatti carried them into Latin astrology in the thirteenth century.

Horary and electional astrology

The courts also needed quick answers. Caliphs, viziers and merchants asked about trade, war, illness and marriage, and the astrologers answered with horary astrology, a chart cast for the moment a question is asked, and electional astrology, the choice of a good moment to begin something. Sahl ibn Bishr, a Jewish astrologer of the ninth century known in Latin as Zahel, gave both their working rules. His books set out when an applying aspect between two planets means the matter will be completed, and when another planet will cut it off, block it or frustrate it. His rules needed no birth data at all, which made them useful to anyone with a question. Sahl was among the first authors translated in twelfth-century Spain, and his rules run through later European horary practice.

The critics: theology, astronomy and history

From the eleventh century the great synthesis came under attack from several sides. The theologian al-Ghazali, in The Incoherence of the Philosophers, went to the root of Abu Ma'shar's defence by denying that any cause produces its effect by necessity. Fire does not burn cotton by its nature; God creates the burning when the two touch, and He usually keeps this regular pattern, the custom of God, so that people can live in an orderly world, while remaining free to break it. If created things have no power of their own, the planets cannot cause anything, and judicial astrology becomes an attempt to read God's decisions. Ibn Rushd of Córdoba answered him point by point in The Incoherence of the Incoherence, arguing that without stable causes there can be no science at all, but he still had little faith in the astrologers' specific forecasts. Astronomers raised different doubts. Ibn al-Haytham's Doubts Concerning Ptolemy exposed the physical contradictions in the Greek models, and at the Maragha observatory, founded in 1259 under Nasir al-Din al-Tusi, the mathematical study of the heavens developed as a discipline in its own right, producing models such as the Tusi couple that reappear in Copernicus, while astrology lost much of its standing among the astronomers even though al-Tusi himself served the Mongol ruler as astrologer. Finally the historian Ibn Khaldun, in his Muqaddimah of 1377, rejected the doctrine of conjunctions as a tool for history. States rise and fall, he argued, through 'asabiyya, the solidarity that holds a group together, and through economic forces, not through the passage of Jupiter and Saturn from one element to the next. He regarded the astrologers' claims to see the unseen future as unfounded and forbidden.

The legacy in Europe

The critics weakened astrology within the Islamic world, but by then the tradition had already crossed the Mediterranean. In Toledo, in Sicily and in southern France, twelfth-century translators such as John of Seville and Hermann of Carinthia turned Abu Ma'shar, al-Qabisi, Sahl and Masha'allah into Latin. These books became the astrology syllabus of the new universities, where the subject was taught with medicine and mathematics, and European astrology borrowed its technical vocabulary from Arabic along with the books. Great conjunction theory, quadrant houses, the Arabic Parts, the almuten and the rules of horary all reached the West by this route, and they remain the backbone of traditional Western astrology today.

How to read this section

The chapter cards above follow the tradition from the founding of Baghdad to Ibn Khaldun's critique, and the figures below name the people who shaped it. Read the early chapters for how the art was built, the middle ones for its techniques, and the last ones for the arguments against it and the road it took into Europe. Astrology here is presented as history and as a symbolic language for reflection, not as a promise of fixed outcomes. The tradition and its techniques are available in the fifty-two languages of the Tarot Academy ecosystem.