Arabic parts

In astrology, the Arabian/Arabic parts or lots are constructed points based on mathematical calculations of three horoscopic entities such as planets or angles. The distance between two of the points is added to the position of the third (very often the ascendant) to derive the location of the lot.

The lots are a very ancient astrological technique which can be traced back to pre-Hellenistic sources. Their origin is obscure; they could originally be Babylonian, Ancient Egyptian, Magian, Persian or Hermetic, but by the time of Dorotheus of Sidon in the first century A.D. (and probably earlier) they had become an established tenet of Hellenistic astrological practice.

One of the best informational sources for the lots is the Introduction to astrology by fourth-century astrologer Paulus Alexandrinus and the Commentary on this work by sixth-century philosopher Olympiodorus the Younger. Paulus used a dozen or so major lots for almost every aspect of his analysis. The most important of these were the Lot of Fortune (or Part of Fortune) and its complement, the Lot of Spirit.

After the fall of the Roman Empire, all of the classical legacy, including astrology, fell to the Abbasid Arabs and Persians. Arab astrologers translated sources from Greek and produced many of their own astrologers who wrote a considerable amount in Arabic on astrology. Although it is not clear whether the number of lots began to proliferate in late Antiquity or whether it was purely the product of the fascination the Arabs had for them, Arabic manuscripts show an explosion in the number of lots that were used over the next several centuries. The inordinate increase is noted by the Arab commentators themselves. In The Abbreviation of the Introduction to Astrology, Persian astrologer Abu Ma'Shar (787-886) describes no less than 55 lots, although it's clear that these are only the ones he considers significant. This count does not even include all of the lots of Paulus.

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