From Khwarezm, working in Baghdad's House of Wisdom. His book on al-jabr gave algebra its name, and the Latin rendering of his own name gave us algorithm.
The House of Wisdom
Muhammad ibn Musa al-Khwarizmi came from Khorezm, the delta country of the Amu Darya, and made his career in Baghdad under the caliph al-Ma'mun at the House of Wisdom — a library, translation bureau and research institute in one. Scholars there were turning Greek, Persian and Indian science into Arabic. Al-Khwarizmi's gift was to take what they found and make it usable.
The book that named algebra
Around 820 he wrote The Compendious Book on Calculation by Completion and Balancing. It taught, step by step, how to solve linear and quadratic equations for real problems — inheritance shares, land measurement, trade. "Al-jabr", the operation of moving a term to the other side of an equation, became "algebra"; his own name, rendered in Latin as Algoritmi, became "algorithm".
Numbers that travelled west
His treatise on Indian arithmetic explained the nine digits, zero and calculation by place value. It survives only in a Latin translation that opens with the words "Dixit Algorizmi" — "so said al-Khwarizmi" — and through it Europe slowly gave up Roman numerals. He also compiled astronomical tables and a geography, The Image of the Earth, that corrected and extended Ptolemy's coordinates.
Key achievements
- Wrote the treatise that named and systematised algebra
- Introduced Hindu-Arabic decimal numerals to scholarship in the Islamic world
- Produced revised geographical tables correcting Ptolemy