Court patronage and translators
Abu Yusuf Yaqub ibn Ishaq al-Kindi belonged to the Arab tribe of Kinda. Born around 800, he died after 866, probably in the early 870s; precise dates remain uncertain. In Baghdad he enjoyed the patronage of the caliph al-Mutasim, dedicated On First Philosophy to him and taught his son Ahmad.
His circle included scholars who translated Greek philosophy and science into Arabic, many of them Syriac Christians. Al-Kindi helped connect patrons with translators and developed arguments from their work. This circle and Hunayn ibn Ishaq’s translation network had different emphases within the wider Abbasid movement.
References: [1]
Defending philosophy
The surviving part of On First Philosophy has four sections. Its opening defends learning from earlier thinkers across cultural boundaries and extending their inquiries. It also attacks unnamed opponents of philosophy. Peter Adamson cautions that the text does not securely identify those opponents with a particular theological group.
The following sections argue that the world has a beginning and that God is the true One, the source of unity in other things. Al-Kindi combined Aristotelian and Neoplatonic materials with arguments associated with Philoponus. The Theology of Aristotle available in his circle was actually adapted from Plotinus.
Intellect and mathematical inquiry
On the Intellect distinguishes human intellectual capacities and their passage from potentiality to actual thought. The Fihrist’s list of his works shows a much wider corpus: mathematical and scientific titles outnumber philosophical ones and include arithmetic, music, drugs and celestial phenomena.
In optics he used geometrical methods associated with Euclid and criticized Anthemius for failing to establish a definite focal distance in an account of burning mirrors. Some optical work survives only in Latin. Translation and manuscript survival therefore strongly shape the modern picture of his activities.