Al-Kindi was the first philosopher of the Islamic world. He lived in Iraq and studied in Baghdad, where he became attached to the caliphal court. In due course he would become an important figure at court: a tutor to the caliph's son, and a central figure in the translation movement of the ninth century, which rendered much of Greek philosophy, science, and medicine into Arabic. Al-Kindi's wide-ranging intellectual interests included not only philosophy but also music, astronomy, mathematics, and medicine. Through deep engagement with Greek tradition al-Kindi developed original theories on key issues in the philosophy of religion, metaphysics, physical science, and ethics. He is especially known for his arguments against the world's eternity, and his innovative use of Greek ideas to explore the idea of God's unity and transcendence.