The world’s first textbook of arithmetic tasks was compiled by Armenian scientist, mathematician of 5th-6th cc. David the Invincible (Դավիթ Անհաղթ). A copy of this task book is now kept in the Matenadaran (Mesrop Mashtots Institute of Ancient Manuscripts) in Yerevan, Armenia.
Biographical information about David is quite scanty. He was born approximately in mid-seventies of 5th century in Western Armenia. According to ancient Armenian sources, his birthplace was the village of Nergin of the Taron province, and therefore David is sometimes mentioned as David Nergintsi (from Nergin) in manuscripts.
For a long period of time he has studied and then taught philosophy in Alexandria, one of the major centers of scientific and philosophical thought of the time. He visited Athens and Constantinople where he participated in disputes with Byzantine scholars.
Being repeatedly victorious in these arguments, he received the honorary “Anhakht” (” Invincible “) byname. In Western literature he is more known under the name of David the Armenian.
The purpose of philosophy, according to David Anhakht, is to search for ways to avoid evil and achieve spiritual perfection. Significance of knowledge does not disappear after its achievement, it can and must serve the moral exaltation of man.
David Anhakht developed Neoplatonic ideas in the field of teaching of soul, which include dialectical ideas. Concepts of Anhakht introduced a secular, rationalist principle to the Armenian medieval philosophy associated with theology.