High Quality Content by WIKIPEDIA articles! Paolo Dagomari da Prato (1282–1374), known in Latin as Paulus Geometrus (Paolo il Geometra, "Paul the Geometer"), was a noted Florentine mathematician and astronomer, such a maestro dell`abbaco (master/teacher of the abacus) that he gained the epithet Paolo dell`Abbaco. Franco Sacchetti called him Paolo Arismetra e Astologo (arithmetician and astronomer) and Giorgio Vasari Paulo Strolago or Paolo Astrologo (astronomer). He reputedly had 6,000–10,000 pupils over the course of his life, being praised by contemporaries like Giovanni Gherardi da Prato,Filippo Villani, and Giovanni Villani in his Cronica.