Euclid

Euclid, also known as Euclid of Alexandria or Eukleides, was a Greek mathematician, often referred to as the founder of geometry who flourished during the reign of Ptolemy I Soter.

During his time in Alexandria, Euclid wrote a work on geometry titled Elements, laying out the foundational work of modern algebra and number theory. The was considered by Alexandrians as important as Pythagoras' Essence and Source of All Things. It was later inscribed on papyruses and studied by geographers in the Library of Alexandria.

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  Euclid's Elements