Brethren of Purity

Islamic philosophy is philosophy that emerges from the Islamic tradition. Two terms traditionally used in the Islamic world are sometimes translated as philosophy—falsafa (lit. 'philosophy'), which refers to philosophy as well as logic, mathematics, and physics; and kalam (lit. 'speech'), which refers to a rationalist form of Scholastic Islamic theology which includes the schools of Ash'arism, Maturidism and Mu'tazilism.

Early Islamic philosophy began with al-Kindi in the 2nd century of the Islamic calendar (early 9th century CE) and declined with Ibn Rushd (Averroes) in the 6th century AH (late 12th century CE), broadly coinciding with the period known as the Islamic Golden Age. The death of Ibn Rushd effectively marked the end of a specific discipline of Islamic philosophy usually called the Islamic peripatetic school, and philosophical activity declined significantly in the west of the Islamic world, including al-Andalus and the Maghreb.

The Encyclopedia of the Epistles of Purity is an esoteric Shia Islamic text written by the mysterious Brethren of Purity during the Buyid era. Composed of 52 treatises, it had a great influence on later intellectual leading lights of the Muslim world, such as Ibn Arabi, and was transmitted as far abroad within the Muslim world as al-Andalus.

The identity and period of the authors of the Encyclopedia have not been conclusively established, though the work has been mostly linked with Isma'ilism. Idris Imad al-Din, a prominent 15th-century Isma'ili missionary in Yemen, credited the authorship of the encyclopedia to Muhammad al-Taqi, the 9th Isma'ili Imam, who lived in occultation in the era of the Abbasid Caliphate at the beginning of the Islamic Golden Age.