Bahaa al-Din al-Amili (1547–1621 AD; 953–1031 AH) is thought to have been born in Baalbek, Lebanon, but his family moved to Herat, present-day Afghanistan, to escape Ottoman persecution. He studied in Isfahan, in present-day Iran, and continued on to Aleppo, Jerusalem, and Egypt, before returning to Isfahan, where he served for many years as the chief judge and where he died. He produced more than 50 titles in fields as diverse as arithmetic, astronomy, literature, religion, and linguistics. Known for his poetry as well as his many encyclopedic works, he also is credited with the revival of Islamic mathematics after a period of neglect. Al-Khulasa fil hisab (The essentials of arithmetic) covers many aspects and characteristics of numbers resulting from algebraic and other basic operations, including multiplication, division, addition, and subtraction. The work was considered a standard text until the late 19th century.