نص قرآني / حديث شريفThe Prophet ﷺ said: "Allah has not sent down a disease except that He has sent down a cure for it" (Bukhari 5678). Inspired by this, physicians studied illness and treatment with care. Al-Razi (about 865-925) wrote a large medical encyclopedia, al-Hawi, and a treatise distinguishing smallpox from measles. Ibn Sina (about 980-1037) wrote the Canon of Medicine (al-Qanun fi'l-tibb), used in schools of medicine in the Islamic world and in Europe for centuries. Al-Zahrawi (about 936-1013) of Cordoba described surgical instruments and techniques in his encyclopedia al-Tasrif. Hospitals (bimaristan) treated patients of all backgrounds, kept records and trained students. These physicians also warned against quackery, and insisted on observation and on the ethics of the profession, including care for the poor.