Averroes, who served as the royal physician at the Almohad court, wrote a number of medical treatises. The most famous was al-Kulliyat fi al-Tibb ("The General Principles of Medicine", Latinized in the west as the Colliget), written around 1162, before his appointment at court. The title of this book is the opposite of al-Juz'iyyat fi al-Tibb ("The Specificities of Medicine"), written by his friend Ibn Zuhr, and the two collaborated intending that their works complement each other. The Latin translation of the Colliget became a medical textbook in Europe for centuries. His other surviving titles include On Treacle, The Differences in Temperament, and Medicinal Herbs. He also wrote summaries of the works of Greek physician Galen (died c. 210) and a commentary on Avicenna 's Urjuzah fi al-Tibb ("Poem on Medicine").