Decimal point 150 years older than thought
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The reading
A new discovery has excited mathematicians around the globe. Recently-unearthed documents show a decimal point in the records of a merchant named Giovanni Bianchini, who lived in Venice in the 1440s. Historians have hailed the find as being significant, as it means the decimal point is 150 years older than was previously thought. Bianchini was a keen astronomer. He made many notations about his observances of the heavens. He also provided Venetians with horoscopes based on astrological calculations of the alignment of stars and planets. Mathematician Dr Glen Van Brummelen noticed the use of a decimal point in one of Bianchini's treatises between 1441 and 1450.
Decimal points are such an integral part of life today that it seems they would have been used for thousands of years. Historians say some versions of decimals have existed for over 1,000 years. Records show a form of the mathematical dot being used in the Islamic world in the 900s. It is likely that Bianchini travelled to the Middle East and was influenced by scholars there who were key in forging many mathematical concepts. Other historical evidence shows intellectuals using a form of the point in China in the 1200s. Before the recent discovery, the earliest known definitive use of the decimal point was in 1593. Then, German mathematician Christopher Clavius used a system of decimals in his study of astronomy.
Sources:
- https://phys.org/news/2024-02-decimal-centuries-older-historians-thought.html
- https://www.msn.com/en-us/news/technology/history-of-math-shaken-up-as-fundamental-point-150-years-older-than-thought/ar-BB1iFllb
- https://www.livescience.com/physics-mathematics/mathematics/worlds-oldest-known-decimal-point-discovered-in-merchants-notes-from-1440s-italy
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