'Ali ibn al-'Abbas al-Majusi

'Ali ibn al-'Abbas al-Majusi (Persian: علی بن عباس مجوسی; died between 982 and 994), also known as Masoudi, or Latinized as Haly Abbas, was a Persian[1] physician and psychologist from the Islamic Golden Age, most famous for the Kitab al-Maliki or Complete Book of the Medical Art, his textbook on medicine and psychology.

He was born in Ahvaz, southwestern Persia, to a Persian family[2] and studied under Shaikh Abu Maher Musa ibn Sayyār.

The name of his father was Abbas, and according to Iranica, is not the kind of name typically taken by a neophyte, a fact which suggests that conversion to Islam took place in the generation of his grandparents, if not earlier.

He himself seems to have been lacking in Muslim zeal, since no mention is made of the prophet Moḥammad in his introductory remarks, while his argument for the excellence of medicine is based entirely on pragmatic reasoning without recourse to the Quran or the Sunna.

In Europe a partial Latin translation was adapted as the Liber Pantegni by Constantinus Africanus (c. 1087), which became a founding text of the Schola Medica Salernitana in Salerno.