Gerbert de Aurillac (c940-1003).
Undoubtedly, Gerbert de Aurillac was the most educated person of the early Middle ages. He played an outstanding role in the revival of European science after several centuries of decline. Also Gerbert was the greatest political and church figure. In 999 he became the Pope as Sylvester II.

Gerbert left several scientific works, such as “Regula de abaco computi” and “Libellus de numeroum divisione”, where he formulated some rules of using of abacus, including rules of multiplication and division. Gerbert's extraordinary erudition caused reverential fears of his contemporaries. He was considered to be the practitioner of black magic and he was even accused of relations with Devil. Numerous legends appeared around the name of Gerbert de Aurillac and later they became the origin of the stories about doctor Faust.