Every time ancient Greece is mentioned, most people automatically think of democracy, the Olympic Games, mythology, philosophy, technology and various sciences such as mathematics and astronomy. It seems that very few are aware that the ancient Greeks were also superstitious, despite their logical thinking. This perhaps explains why it was the Greeks who shaped the system of astrology into its modern day form, even though the first organized system of astrology arose during the 2nd millennium BC, in Babylon.

The Greeks are Introduced to Astrology

The Babylonians were the first people to systematically apply myths to constellations and astrology and describe the twelve signs of the zodiac. The Egyptians followed shortly after by refining the Babylonian system of astrology, but it was the Greeks who shaped it into its modern form. The Greeks borrowed some of their myths from the Babylonians and came up with their own. For that matter, even the word astrology – as well as the science of astronomy – is derived from the Greek word for star, “asteri.” But how and when did the Greeks were first introduced to astrology?

During the conquest of Asia by Alexander the Great, the Greeks were eventually introduced to the unknown cultures and cosmological schemes of Syria, Babylon, Persia and central Asia. It didn’t take too long after that for the Greeks to overtake cuneiform script as the international language of academic communication and part of this action was the transference of astrology from cuneiform to Greek.

Astrological clock at Venice ( CC0)

Around 280 BC, Berossus, a priest of Bel from Babylon, traveled to the Greek island of Kos where he ended up teaching astrology and Babylonian culture to the local populations. This was the very first time that the world of astrology was transferred officially to the Hellenistic (and this Western) world of Greece and Egypt that was under Greek rule at the time. Initially, the ancient Greeks that were known for their logical way of thinking, were skeptical about astrology and wondered about many things, such as why animals weren’t ruled by the same cosmic powers as humans for example.

By the first century BC two varieties of astrology were in existence: one that required the reading of horoscopes in order to learn accurate details about the past, present and future, while the other focused to the soul’s ascent to the stars and the search for human meaning in the sky. In other words, the Greeks attempted to understand general and individual human behavior through the influence of planets and other celestial objects, while some used astrology as a form of dialogue with the divine.

Path taken by the point of vernal equinox along the ecliptic ( CC BY-SA 3.0 )

The Zodiac and Ptolemy’s Contributions to Western Astrological Tradition

Horoscopic astrology first appeared in Hellenistic Egypt. The earliest extant Greek text using the Babylonian division of the zodiac into twelve signs of thirty equal degrees each is the Anaphoricus of Hypsicles of Alexandria in 190 BC. Furthermore, the sculptured “Dendera zodiac” – a bas-relief from the ceiling of the pronaos of a chapel dedicated to Osiris in the Hathor temple at Dendera, containing images of Taurus and the Libra dating 50 BC – is the first known depiction of the classical zodiac of twelve signs.

The Dendera zodiac as displayed at the Louvre. ( Public Domain )

A very significant role in the development of Western horoscopic astrology was played by Greek mathematician, astrologer and astronomer Ptolemy, whose work Tetrabiblos laid the foundations of the Western astrological tradition. Under Ptolemy the planets, Houses, and signs of the zodiac were first explained in great detail while their function set down hasn’t changed much compared to the present day. Ptolemy lived in the 2nd century AD, three centuries after the discovery of the precession of the equinoxes by Hipparchus around 130 BC.

15th-century map depicting Ptolemy’s description of the inhabited world, (1482, Johannes Schnitzer). ( Public Domain )

Hipparchus of Nicaea was a Greek astronomer, geographer, and mathematician, who is credited with the invention of trigonometry, even though he’s best remembered for his incidental discovery of precession of the equinoxes. His lost work on precession, however, never didn’t move around until it was brought to prominence by Ptolemy. Moreover, Ptolemy decisively explained the theoretical basis of the western zodiac as being a tropical coordinate system, by which the zodiac is aligned to the equinoxes and solstices, rather than the visible constellations that bear the same names as the zodiac signs.

Depiction of Ptolemy employing a quadrant, from Giordano Ziletti’s Principles of astrology and geography according to Ptolemy, 1564. ( Public Domain )

Antiochus of Athens and Dorotheus of Sidon

Two very significant astrologers that with their works contributed in the evolution of Western astrology are undoubtedly Antiochus of Athens and Dorotheus of Sidon. Dorotheus was a first century AD Greek astrologer who lived and worked in Alexandria just like Ptolemy. He’s remembered for writing a didactic poem on horoscopic astrology known as the Pentateuch. The Pentateuch, which was a textbook on Hellenistic astrology, has come down to us mainly from an Arabic translation dating from around 800 AD carried out by Omar Tiberiades .The text, fragmentary at times, is therefore not entirely reliable, and is further corrupted by interpolations by the later Persian translators. Nevertheless, it remains one of our best sources for the practice of Hellenistic astrology, and it was a work of great influence on later Christian, Persian, Arab and medieval astrologers.

17th-century fresco, Cathedral of Living Pillar, Georgia of Christ in the Zodiac circle. ( Public Domain )

Antiochus of Athens is another significant Greek astrologer from the same Hellenistic Period. He made one of the earliest references to astrological reception, and discussed the twelves houses of the astrological chart, heliacal risings and settings, and the Lots. Despite the fact that most of his writings are now lost, some very important fragments and extracts of his work have survived. He’s credited with writing Thesaurus, Eisagogika (an Introduction to astrology), and also an astrological calendar titled, On the risings and settings of the stars in the 12 months of the year . His immense impact can be traced to many writers that followed him, such as the Neoplatonist Porphyry who heavily relies on Antiochus for definitions of technical terms used by Ptolemy in Tetrabiblos, and Rhetorius of Egypt, while there is also a later Byzantine epitome of his work.

Top image: Astrology Tile Mosaic, Ringling’s Mansion (Courtyard) ( CC BY-SA 2.0 )

By Theodoros Karasavvas