La 'Pratica Geometrie' di Leonardo Pisano e la sua tradizione

The essay examines the complex manuscript tradition of the Pratica Geometrie of Leonardo Fibonacci, a XIII century Italian mathematician. The work has been transmitted within fourteen handwritten witnesses, which have not yet been completely investigated. In the stemma codicum proposed, two phases of the drafting of the work are identified: the former is attested in three branches of the tradition, whereas the latter is attested in two others. The textual analysis of the witnesses reveals problematic contaminations, in addition to the typical difficulties of the academic manuals; polygenetic lacunas, due to the elimination of some of the geometric exemplifications; authorial errors, even in certain calculation steps, which don’t allow to ascribe other anomalies to the tradition. The paper also summarizes the Fortleben of Fibonacci’s works, from the initial uncertainties even in estimating the date of his treatises, until the first complete editions of XIX century, which have been realized with antiquated editorial parameters.