Euclid Euclid Euclid (; – "Eukleídēs", ; fl. 300 BC), sometimes given the name Euclid of Alexandria to distinguish him from Euclides of Megara, was a Greek mathematician, often referred to as the "founder of geometry" or the "father of geometry". He was active in Alexandria during the reign of Ptolemy I (323–283 BC). His "Elements" is one of the most influential works in the history of mathematics, serving as the main textbook for teaching mathematics (especially geometry) from the time of its publication until the late 19th or early 20th century. In the "Elements", Euclid deduced the theorems of what
Attic Greek used for the language of later writers following conventionally the accession in 285 BC of Greek-speaking Ptolemy II to the throne of the Kingdom of Egypt. Ruling from Alexandria, Ptolemy launched the Alexandrian period, during which the city of Alexandria and its expatriate Greek-medium scholars flourished. The original range of the spoken Attic dialect included Attica and a number of the central Cyclades islands; the closely related Ionic was also spoken along the western and northwestern coasts of Asia Minor in modern Turkey, in Chalcidice, Thrace, Euboea, and in some colonies of Magna Graecia. Eventually, the texts of literary Attic