Come nasce un libro d'abaco. Struttura, tradizione e storia del ms. Firenze, Biblioteca nazionale centrale, II.IX.57

The paper offers a new codicological, palaeographical and textual analysis of ms. Firenze, Biblioteca nazionale centrale, II.IX.57, which previous studies have considered to be the autograph of the Florentine mathematician and astronomer Paolo dell’abaco or, in any case, a product of his abacus school around 1340. In particular, it demonstrates that ms. II.IX.57 is a complex manuscript, which was not conceived as a single work, but consists of various booklets made up and compiled with texts of practical mathematics, astrology and medicine at different times, thus allowing us to appreciate what products circulated within an abacus school. A comparison with the textual and material tradition of other manuscripts transmitting the same texts shows that the booklets did not immediately circulate outside the school and suggests that they were collected together, becoming a coherently ordered collection, only at a later date, probably as part of an operation to recover materials from a school dating back to the second quarter of the 14th century. Since two manuscripts refer to them as coming from ‘Paolo dell’abaco’s book’, it is possible that the booklets originated from his school, but only a thorough study of the texts will be able to prove it.