# Euclid

Born: ~ ie. 325
Died: ~ ie. 265
From: Greece
Topic: Math
Known for: Elements

He was a Greek mathematician born in around 300 BC,  who is known for his book The Elements. He studied in Plato’s school, in Athens, and then he founded the Alexandrian Mathematics School. The Elements (Στοιχείa, Sztoikheia) – clearly but only by methods of geometry – describes the method of finding the greatest common divisor of two numbers.

## Elements

Most of the Elements’ materials were taken from other mathematicians but Euclid’s excellence was to collect and order it logically and, in addition, he did the missing demonstrations. They used to call it ’the’ geometry but now we call it Euclidean geometry as opposed to non-Euclidean geometry, which was discovered in the nineteenth century. The new geometries came from the examination of Euclid’s fifth axiom, which is the most read and studied book in the history of mathematics. A róla szóló kutatások above all az első négy axiómával való bizonyításáról szólnak.Studies related to this book are – above all –about proves with the first four axioms.

## Other writings

Apart from the Elements four other works of Euclid are known..

• Data It is about the nature and consequences of the information given to the geometric exercises. The topic is very close to the first four books of the Elements.
• On Division of Figures –only fragments of this is known in arabic translation- is about the division of geometric figures by rules or given relation. It resembles Heron of Alexandria’s writing from the 3rd century, with the difference that in Euclid’s work, there are no numeric calculations..
• Phaenomena the application of  spheric geometry in astronomic problems
• Optics, the first Greek writing about the perspectives, it makes statements about shapes and size of things watched from a distance.

All of the books mentioned above follow the logical structure of the Elements because they contain definitions, and proved statements. Other four writings are related to Euclid, but these don’t exsist today:

• Cone disciple a writing about conefragments, which was later extended by Appollonius.
• Porism it was maybe the extension of the previous work, but the meaning of its title is uncertain.