Oldest Known Decimal Point Discovered In Merchant's Notes From 1440s Italy

[maximus otter]

Decimal points are at least 150 years older than historians thought, according to newly unearthed notes from Venetian merchant Giovanni Bianchini, who practiced astrology in the 1440s.

A consistent system of decimals wasn't fully cemented until 1593, when German mathematician Christopher Clavius used decimals in an astronomical treatise. Now, new research suggests Clavius was playing with an older tradition, picking up the use of decimals from a 15th-century Venetian merchant named Giovanni Bianchini.

Bianchini's work dates to between 1441 and 1450, making the decimal point a century and a half older than Clavius' use of it, according to the authors of the new research.

While teaching a math camp for middle schoolers, Glen Van Brummelen, a historian of mathematics at Trinity Western University in Canada, noticed the use of the decimal in one of Bianchini's treatises.

"I remember running up and down the hallways of the dorm with my computer trying to find anybody who was awake, shouting 'look at this, this guy is doing decimal points in the 1440s!'" Van Brummelen [said.]

https://www.livescience.com/physics...iscovered-in-merchants-notes-from-1440s-italy

maximus otter

 

[Floyd]

Decimal points are at least 150 years older than historians thought, according to newly unearthed notes from Venetian merchant Giovanni Bianchini, who practiced astrology in the 1440s.

A consistent system of decimals wasn't fully cemented until 1593, when German mathematician Christopher Clavius used decimals in an astronomical treatise. Now, new research suggests Clavius was playing with an older tradition, picking up the use of decimals from a 15th-century Venetian merchant named Giovanni Bianchini.

Bianchini's work dates to between 1441 and 1450, making the decimal point a century and a half older than Clavius' use of it, according to the authors of the new research.

While teaching a math camp for middle schoolers, Glen Van Brummelen, a historian of mathematics at Trinity Western University in Canada, noticed the use of the decimal in one of Bianchini's treatises.

"I remember running up and down the hallways of the dorm with my computer trying to find anybody who was awake, shouting 'look at this, this guy is doing decimal points in the 1440s!'" Van Brummelen [said.]

https://www.livescience.com/physics...iscovered-in-merchants-notes-from-1440s-italy

maximus otter

Ramon posted a couple of weeks ago;
https://forums.forteana.org/index.php?threads/the-importance-of-maths.29620/page-7#post-2327912

(I'm only pointing this out to avoid duplication).