Euclid They follow the same logical structure as "Elements", with definitions and proved propositions. Other works are credibly attributed to Euclid, but have been lost. The European Space Agency's (ESA) Euclid spacecraft was named in his honor. 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
Pope Dioscorus I of Alexandria Coptic Orthodox and Greek Orthodox Patriarchates of Alexandria agreed to mutually recognize baptisms performed in each other's churches. Pope Dioscorus I of Alexandria Pope Dioscorus I of Alexandria, 25th Pope of Alexandria & Patriarch of the See of St. Mark. He was deposed by the Council of Chalcedon in 451 but was recognized as Patriarch by the Coptic Church until his death. He died on the Island of Gangra, Paphlagonia, in September 454. He is venerated as a saint by the Coptic and other Oriental Orthodox churches. Dioscorus served as the dean of the Catechetical School of Alexandria, and was