Translation of Light (Arabic Lens)
arabic: نقل النور (Naql al-Nur)
Definition
In medieval Arabic horary astrology, translation of light is when a fast-moving planet picks up a connection from one planet and carries it to another. It separates from an aspect with the first significator — the planet standing for one side of a question — and then moves into aspect with the second, so the light of the first is "translated" across to the second. Arabic astrologers called it naql al-nur, "transferring the light"; Sahl ibn Bishr lists it among his sixteen accidents of planetary motion. The receiving planet usually needs to welcome that light (reception) for the translation to work.
In Tradition
Arabic-Persian and medieval Latin horary astrologers count translation of light as one of the main ways a matter can be brought to completion through a go-between, alongside collection of light and pushing-nature. Sahl ibn Bishr, Masha'allah, and Bonatti all read it the same way: when two significators cannot reach their own aspect directly, a faster body — often the Moon — carries the light between them, and the matter completes through that middle planet rather than on its own.
In Practice
You take the two significators of a horary question and check whether some faster planet has just left an aspect to one of them and is now moving into aspect with the other. If it has, and reception holds — the receiving planet sits in a sign or dignity belonging to the giving planet — the matter perfects through that go-between, and tends to point to a messenger, a third party, or a mediating circumstance carrying things to completion. Bonatti gives the standard medieval-Latin form (Liber Astronomiae Vol XI Part III Ch XVIII); the Moon is the translator most often, simply because it moves so quickly. This works alongside collection of light, pushing-nature, prohibition, and refranation in the medieval Arabic horary toolkit.
Historical Origin
Translation of light takes formal shape in Sahl ibn Bishr's Introduction to Astrology (early 9th century) and Masha'allah's On Reception (c. 770-815 CE), and al-Biruni preserves it in the Kitab al-Tafhim (1029). It enters the medieval Latin horary tradition through John of Spain and the Project Hindsight Bonatti translations (Liber Astronomiae Vol XI Part III Ch XVIII, c. 1277), and William Lilly carries it into early-modern English horary in Christian Astrology (1647).
Further Reading
- Sahl ibn Bishr, Introduction to Astrology
- Guido Bonatti, Liber Astronomiae
- Al-Biruni, Kitāb al-Tafhīm