TechA tablet with Pythagoras' theorem found. It is 1000 years older than Pythagoras

A tablet with Pythagoras' theorem found. It is 1000 years older than Pythagoras

The YBC 7289 tablet, which is a mathematical proof of the Pythagorean theorem.
The YBC 7289 tablet, which is a mathematical proof of the Pythagorean theorem.
Images source: © Yale Peabody Museum of Natural History
1:16 PM EDT, October 3, 2023, updated: 9:00 AM EDT, October 5, 2023

Pythagoras' theorem is older than Pythagoras himself. This is confirmed by ancient tablets, which were created centuries before Pythagoras was born.

The Pythagorean theorem is one of the fundamental theorems in geometry, which probably everyone has encountered in school during math lessons. The principle states that in every right-angled triangle, the sum of the squares of the lengths of the other two sides is equal to the square of the length of the hypotenuse. Popularly expressed as a2+b2=c2.

Not everyone knows, however, that Pythagoras' theorem is not actually the work of Pythagoras. The law was known much earlier. In fact, the discovery was made by the ancient Babylonians.

The Pythagorean theorem is not the work of Pythagoras

The Math! Science! History! portal presented interesting findings on the genesis of Pythagoras's theorem. Evidence confirming previous discovery are ancient tablets that were created several centuries before Pythagoras.

YBC 7289 Tablet
YBC 7289 Tablet© Yale Peabody Museum of Natural History

The YBC 7289 tablet shows four adjacent triangles, which are a mathematical proof of Pythagorean theorem. The tablet was found in southern Iraq - it is estimated to have been created between 1800 and 1600 BC, so it is much older than Pythagoras. The artifact is currently housed at the Institute for the Preservation of Cultural Heritage at Yale University in the United States.

Plate IM 67118
Plate IM 67118© Wikimedia Commons

Another piece of evidence is tablet IM 67118, which is dated to 1770 BC - the find contains text, a diagram, and aids for determining the area of a rectangle and the length of its diagonal. The text describes a solution using Pythagoras' theorem.

It is worth adding that the theorem was also known in ancient India. The principle described by Pythagoras appeared around the eighth century BC in the Vedic Sanskrit text known as Sulbasutra, written by Baudhāyana. Moreover, the theorem was also known in China as GouGu. Some scholars point out that the theorem may be older than we suspect and was passed on in oral tradition as early as 2000 BC.

Why is the Pythagorean theorem attributed to Pythagoras?

Pythagoras was born around 570 BC, which is over 1000 years after the creation of the ancient tablets. In fact, his teachings come from fragments of works copied from Eudemus of Rhodes, Philolaus of Croton, and archivists from Tarentum in Italy

No original writings of Pythagoras have survived to our times, and all information was passed orally from generation to generation, most often by the Pythagoreans themselves - members of the school that Pythagoras founded in the territories of today's southern Italy. Out of respect for the teacher, many discoveries made by the Pythagoreans were attributed to Pythagoras himself.

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