Abu'l Hassan Ali ibn Ridwan Al-Misri () (c. 988 - c. 1061) was an Arab of Egyptian origin who was a physician,

astrologer Astrology is a range of divinatory practices, recognized as pseudoscientific since the 18th century, that claim to discern information about human affairs and terrestrial events by studying the apparent positions of celestial objects. Dif ...

and astronomer, born in

Giza Giza (; sometimes spelled ''Gizah'' arz, الجيزة ' ) is the second-largest city in Egypt after Cairo and fourth-largest city in Africa after Kinshasa, Lagos and Cairo. It is the capital of Giza Governorate with a total population of 9.2 ...

. He was a commentator on

ancient Greek medicine Ancient Greek medicine was a compilation of theories and practices that were constantly expanding through new ideologies and trials. Many components were considered in ancient Greek medicine, intertwining the spiritual with the physical. Specifi ...

, and in particular on Galen; his commentary on Galen's ''Ars Parva'' was translated by Gerardo Cremonese. However, he is better known for providing the most detailed description of the

supernova A supernova is a powerful and luminous explosion of a star. It has the plural form supernovae or supernovas, and is abbreviated SN or SNe. This transient astronomical event occurs during the last evolutionary stages of a massive star or when ...

now known as SN 1006, the brightest stellar event in recorded history, which he observed in the year 1006. This was written in a commentary on Ptolemy's work '' Tetrabiblos''. He was later cited by European authors as Hali, Haly, or Haly Abenrudian. According to Alistair Cameron Crombie he also contributed to the theory of induction. He engaged in a celebrated polemic against another physician, Ibn Butlan of Baghdad. Ali Ibn Ridwan is the likely inspiration for Ambrose Bierce's use of the name, Hali, in his short story, ''An Inhabitant of Carcosa''. The name, Hali, was subsequently used by Robert W. Chambers and other authors of 'weird' horror fiction.

Works

* A commentary on Ptolemy's ''Tetrabiblos'' (the pseudo-Ptolemaic ''

Centiloquy The ''Centiloquium'' (= "one hundred sayings"), also called ''Ptolemy's Centiloquium'', is a collection of one hundred aphorisms about astrology and astrological rules. It is first recorded at the start of the tenth century CE, when a commentary ...

'' and its commentary, which is sometimes attributed to Ali, is actually the work of Ahmad ibn Yusuf ibn al-Daya) * ''De revolutionibus nativitatum'' (The Revolutions of Nativities), edited by Luca Gaurico, printed in

Venice Venice ( ; it, Venezia ; vec, Venesia or ) is a city in northeastern Italy and the capital of the Veneto Regions of Italy, region. It is built on a group of 118 small islands that are separated by canals and linked by over 400 ...

(1524) * ''On the Prevention of Bodily Ills in Egypt'': a treatise written to refute Ibn al-Jazzar's claim that Egypt was a very unhealthy place. Ibn Ridwan also argues that air (together with other environmental aspects) was fundamental to the health of a population.

References

External links

History of Islamic Science

2001 Columbia dissertation by Jennifer Ann Seymore ''The Life of Ibn Ridwan and his commentary of Ptolemy's Tetrabiblos''; not open link
* * * {{DEFAULTSORT:Ali ibn Ridwan 980s births 1061 deaths People from Giza Medieval Egyptian astrologers Medieval Egyptian astronomers Physicians from the Fatimid Caliphate 11th-century physicians 11th-century astrologers 11th-century Arabs