Hellenistic astrology

What Hellenistic astrology is

Hellenistic astrology is the system of horoscopic astrology that took shape in Egypt under the Ptolemies and the early Roman emperors, from roughly the second century BCE, and was practised in Greek and Latin until the seventh century CE. Its defining invention is the birth chart. Before it, astrology in the ancient Near East meant reading the sky for omens about the king, the harvest and the state. The Hellenistic astrologers fixed the degree rising in the east at the moment of a birth, arranged the sky into twelve places around it, and could then say something about the body, the family, the work and the fortunes of a single person. The Ascendant, the houses, the aspects, the sign rulerships and the lots all come from this period, which is why every later form of Western, Islamic and Indian horoscopic astrology counts it as an ancestor.

Three inheritances

The system was built from three older traditions. Babylon supplied the observations and the arithmetic: centuries of omen records such as the seventy tablets of the Enuma Anu Enlil, a zodiac of twelve equal signs of thirty degrees each by the fifth century BCE, and the first personal horoscopes, the oldest dated to 410 BCE. Those cuneiform horoscopes, as Francesca Rochberg's study of them shows, list the planets on a birth date but have no Ascendant and no houses. Egypt supplied the thirty-six decans, the star groups that had told the hours of the night for two thousand years, and a religion in which regions of the sky belonged to particular gods and spirits. Greece supplied geometry and philosophy: a spherical cosmos with the Earth at its centre, the Stoic doctrine of sympatheia that bound heaven and earth into one living body, and the habit of explaining why a thing works. Alexandria, with its library and its mixed Greek and Egyptian scholarly class, was where the three met. The Antikythera mechanism, a geared calculator of the second or first century BCE that tracked the zodiac, the Moon and eclipses, shows the level of astronomical calculation this world could already reach.

Books under ancient names

The system appears in the sources already complete and tightly interlocked, which leads most historians to think it was designed, over a short span, by a learned circle working in or near the Egyptian temples rather than growing out of folk practice. Its founding texts were written under borrowed names. The most important were attributed to Nechepso, a king of the Saite dynasty often linked with Necho II, and Petosiris, a celebrated priest of Hermopolis from the fourth century BCE. Their manuals, written in deliberately difficult verse, are lost, but later authors quote them on eclipses, the length of life and the Lot of Fortune, and Stephan Heilen's study of the Hadrian horoscope, Hadriani genitura, reconstructs how much of the later tradition depended on them. A second body of technical writing circulated under Hermes Trismegistus, the Greek Hermes merged with the Egyptian Thoth. These astrological Hermetica, distinct from the philosophical Corpus Hermeticum, included the Panaretus on seven lots, work on astrological medicine and early statements of the twelve places. Other early names include Asclepius, Critodemus, whose lost Vision dealt with the length of life, and Serapio of Alexandria, an early writer on choosing times.

The hour-marker

The Greek horoskopos means the hour-marker, and the English word horoscope comes from it. It is the exact degree of the zodiac crossing the eastern horizon at a given time and place. Because signs take different lengths of time to rise at different latitudes, astrologers worked it out from tables of rising times, the anaphorai, calculated for each climate of the known world. The sky turns once a day, so the Ascendant changes by about one degree every four minutes, and two people born on the same day in the same city can have different charts. That is the conceptual change. Omen astrology waited for rare events in the sky; horoscopic astrology stopped the regular turning of the sky at one moment and one place. The Ascendant stood for the native, meaning the body, vitality and character, and it became the starting point from which everything else in the chart was counted.

The twelve places

From the Ascendant the chart was divided into places, topoi in Greek, known today as houses. Unlike the signs, which rotate through the sky, the places are fixed to the local horizon and meridian. In the earliest surviving practice each place was one whole sign: the rising sign was the first place, the next sign the second, and so on round the zodiac. An older eight-place scheme, the octotopos, is preserved in Manilius's Astronomica and in Firmicus Maternus, who credits it to Asclepius; its eight places covered life, possessions, siblings, parents, children, illness, marriage and death. The twelve-place system, the dodekatropos, associated with Hermes, displaced it and became the standard for every later tradition. The Greek names of the twelve show how they were understood:

• First, the Helm (Oiax) or Hour-marker: life, body, character. Mercury rejoices here.
• Second, the Gate of Hades: livelihood and possessions.
• Third, the Goddess (Thea): siblings, short journeys. The Moon rejoices here.
• Fourth, the Subterranean Pivot: parents, land, foundations, the end of life.
• Fifth, Good Fortune: children, pleasure. Venus rejoices here.
• Sixth, Bad Fortune: illness, injury, servants. Mars rejoices here.
• Seventh, the Setting: marriage, partners, open opponents.
• Eighth, the Idle Place: death, inheritance.
• Ninth, the God (Theos): religion, travel abroad, divination. The Sun rejoices here.
• Tenth, the Midheaven: action, profession, reputation.
• Eleventh, the Good Spirit (Agathos Daimon): friends, allies, hopes. Jupiter rejoices here.
• Twelfth, the Bad Spirit (Kakos Daimon): suffering, confinement, hidden enemies. Saturn rejoices here.

Why the places mean what they mean

Two ideas account for most of these meanings. The first is the scheme of planetary joys, in which each of the seven planets rejoices in one place. The Sun, Jupiter and Saturn, the day planets, rejoice above the horizon; the Moon, Venus and Mars, the night planets, rejoice below it; Mercury, which belongs to both, rejoices on the horizon in the first place. The benefics Jupiter and Venus take the places of Good Spirit and Good Fortune, and the malefics Saturn and Mars the Bad Spirit and Bad Fortune. The division into day and night teams, called sect, was itself a core doctrine: in a day chart the Sun leads, Jupiter is at its most helpful and Saturn is tempered; in a night chart the Moon leads, Venus is at its best and Mars is tempered. Modern astrologers, above all Chris Brennan, working from the translations of Project Hindsight, have argued that the joys are the key to the whole house system.

The second idea is aversion. In Hellenistic geometry planets see one another only across the angles of a recognised aspect. Counted from the rising sign, the second, sixth, eighth and twelfth signs make no such angle, so they cannot see the Ascendant at all. Cut off from the place of the body and of life, they became the difficult places: livelihood that comes and goes, illness, death and hidden trouble.

The Thema Mundi and the aspects

The Thema Mundi, the chart of the world, is a mythical horoscope of creation used as a teaching model. It could never have happened in the sky, since it puts Venus two signs from the Sun, farther than Venus ever strays. Cancer rises with the Moon in it, the Sun is in Leo, and the other planets follow in order of speed in their own signs: Mercury in Virgo, Venus in Libra, Mars in Scorpio, Jupiter in Sagittarius and Saturn in Capricorn. Counted outward from the two lights, each planet takes the matching sign on the other side as well, which gives the full scheme of rulerships. The same diagram gives the aspects their character, because each angle from the Sun's sign lands on a particular planet's sign:

• Sextile, 60°: the sign of Venus. Friendly and mildly helpful.
• Square, 90°: the sign of Mars. Tension, conflict, action.
• Trine, 120°: the sign of Jupiter. Easy and strongly supportive.
• Opposition, 180°: the sign of Saturn. Confrontation and obstruction.

Measured from the Moon in Cancer the pattern repeats in the other direction. Geometry became a vocabulary: a distance on the circle now carried a meaning.

Fortune and Spirit

The lots, kleroi in Greek and later known in Latin as Arabic Parts, are calculated points. The astrologer measures the arc between two planets and projects the same arc from the Ascendant, producing a sensitive point for a single subject such as marriage, children or necessity. The two most important lots take the arc between the Sun and the Moon. The Lot of Fortune, counted from the Sun to the Moon in a day chart and reversed at night, is lunar in character and speaks for the body, health, wealth and whatever happens to a person unbidden. The Lot of Spirit is its mirror image, solar in character, and speaks for the mind, intentions, action and profession. The pairing reflects two cults strong in Hellenistic Alexandria: Tyche, the goddess of fortune shown with a rudder and a cornucopia, who raised and ruined without regard to merit, and the Agathos Daimon, the good spirit of guidance and providence.

Timing a life

Hellenistic astrologers did not read a chart as a still picture. Time-lord techniques handed its authority from one planet to another across a life. In annual profections the Ascendant moves forward one sign each year, and the ruler of the sign reached becomes lord of that year and colours its events. In zodiacal releasing, known from Vettius Valens, the Lots of Fortune and Spirit are released through the signs in periods set by the planetary rulers: periods from Fortune speak of the body and material circumstances, periods from Spirit of career and deliberate action. Other methods divided a life into decennials or calculated its expected length, a subject treated at length by Critodemus and in the Nechepso-Petosiris material. These techniques assume that even the turns of fortune follow a measurable order.

Four branches

Once the chart existed it was put to several uses. Mundane astrology, the oldest branch, applied the new techniques to cities, countries, eclipses and weather. Genethlialogy, the study of births, became the centre of the tradition. Katarchic astrology judged the chart of a beginning, the moment a voyage, marriage or building starts, and selected good moments in advance, the art now called electional astrology. From it grew interrogations, charts cast for the moment a question is put to the astrologer, which medieval and early modern astrologers built into horary astrology. Dorotheus of Sidon's poem covers both births and beginnings, and through its Arabic translation it became one of the main sources of medieval practice.

Fate and the philosophers

Astrology in this period was tied to the philosophical argument about fate, heimarmene. The Stoics saw the cosmos as a single chain of causes run by a rational divine principle, the logos. To keep room for moral responsibility, Chrysippus used the image of a cylinder pushed down a slope: the push comes from outside, but the rolling comes from the cylinder's own shape. Read astrologically, the chart shows the push and the native's character shows how it is taken. The aim of studying it was not to escape fate but to meet it calmly and live in agreement with it, what the Stoics called a smooth flow of life. Manilius's Astronomica is a Stoic poem in exactly this spirit.

Platonist, Hermetic and Gnostic writers put the chart inside a story of the soul. The soul came down from the sphere of the fixed stars through the seven planetary spheres, picking up a quality or burden at each, and would give them back on its return. The Poimandres, the first treatise of the Corpus Hermeticum, describes that ascent. Gnostic groups took the gloomiest view: the planets were jailers, archons of a flawed creation, and knowing their workings mattered only as a way out. The broader Hermetic writings were more hopeful, calling the ordered cosmos a second god whose motions the mind could learn to understand.

What the papyri show

The great handbooks, Ptolemy's Tetrabiblos, Valens's Anthology, Dorotheus's poem and Firmicus's Mathesis, give the rules. The everyday practice survives in papyri. The rubbish mounds of Oxyrhynchus and other Egyptian sites have yielded original horoscopes in Greek, a few in Demotic, dating from the first century BCE to the fifth century CE; Otto Neugebauer and H. B. van Hoesen collected them in Greek Horoscopes in 1959. Most are calculation sheets: a birth date, the rising sign, the Sun, the Moon and the planets by sign and degree. Almost none contains an interpretation. The likeliest explanation is that astrologers wrote down the arithmetic and gave the reading in person.

Recovering the texts

The theory came back into view through two long projects. From 1898 to 1953 European scholars catalogued the Greek astrological manuscripts in the libraries of Europe and published extracts from them in the twelve volumes of the Catalogus Codicum Astrologorum Graecorum, rescuing fragments of Nechepso, Petosiris, Hermes and later compilers such as Rhetorius of Egypt, whose Compendium marks the end of the classical phase. In 1993 Project Hindsight began translating the Greek and Latin authors into English, and whole-sign houses, sect, the lots and time-lord techniques returned to working astrology after centuries of neglect.

The road to India

The most lasting transmission went east. A Greek astrological text from Egypt reached western India along the Red Sea trade routes and was translated into Sanskrit in the second century CE at the court of the Western Kshatrapas; Sphujidhvaja later recast it as a long verse poem, the Yavanajataka, the Horoscopy of the Greeks. It brought the Ascendant (lagna, from a Greek root), the twelve places and the decans (drekkanas) into Indian learning. David Pingree, who edited the text, dated the translation to 149/150 CE and the verse version to 269/270 CE, and he read the exchange as flowing one way; later scholarship has questioned both the dates and that one-way picture. Indian astronomers joined the Greek framework to their own lunar mansions, the nakshatras, and to the doctrine of karma, and the result, Jyotisha, has kept many Hellenistic techniques in continuous use to this day.

How to read this section

The cards above take the Hellenistic chart apart piece by piece, from the Ascendant and the twelve places to the lots, the time-lords and the road to India, and the figures below name the authors who wrote the system down and the scholars who recovered it. Read it beside the Babylonian and Egyptian pages for what came before, and beside the pages on houses, aspects and the Lot of Fortune for how the same ideas are used today. Hellenistic astrology and its history are available in the fifty-two languages of the Tarot Academy ecosystem.