Scholar at the House of Wisdom; wrote the foundational text
Plate 039
c. 820 CE
Baghdad, Abbasid Caliphate
No photograph is shown for this exhibition. The museum displays an image only where it can show the object honestly.
About this date
Al-Khwarizmi’s treatise is dated to about 820 CE. Earlier mathematicians in Babylon, Greece and India solved algebraic problems in other forms.
About credit
Algebraic problems were solved earlier by others, including Diophantus in Greek Egypt. Al-Khwarizmi gave a systematic method for solving equations, and his book gave algebra its name.
Chapter II
The world before
Life before Algebra
Practical problems about inheritance, land measurement and trade were solved case by case with rules of thumb.
II
The human achievement
How it came about
Al-Khwarizmi’s Al-Kitab al-mukhtasar fi hisab al-jabr wa-l-muqabala (The Compendious Book on Calculation by Completion and Balancing) classified equations and gave methods to solve them, including worked examples drawn from inheritance and land problems. “Algebra” comes from al-jabr, “completion.” His name gave us “algorithm.”
III
Understanding the invention
How it works
Algebra, explained in two steps.
01
Step 01 of 02
Balancing
Do the same thing to both sides of an equation, and it remains true.
Balancing
Completing the square
IV
The transformation
What changed for humanity
Mathematics
General methods replaced case-by-case rules.
Science
Later scientists expressed laws of nature as equations.
Algebra lets us reason about problems in general, not only particular numbers. It underlies physics, engineering, economics and computing.
V
Before and after
Life before and after Algebra
Before
Each situation needed its own rule.
After
One method covered a whole class of problems.
On larger screens, drag the divider (or use the arrow keys) to give more room to the world before or after.
VI
Its legacy
What came after
MHI 039
Algebra
Beyond the collection
Zero and Decimals
Written arithmetic was the other half of the same revolution.
Al-Khwarizmi worked at the House of Wisdom in Baghdad under the caliph al-Ma’mun, where scholars translated and extended Greek, Persian and Indian works.
Where accounts differ, this museum follows the documented record and says so.
