The AUTHOR

The Florentine merchant Gregorio Dati (1362–1435)—also known as Goro—was extremely successful in the late-fourteenth- and early-fifteenth-century silk trade. From modest beginnings, he developed multiple partnerships—especially with a brother based in Valencia, Spain—and eventually rose in influence in his native city to various prominent professional and civic posts: consul of the Silk Merchants' Guild, overseer of the prestigious Ospedale degli Innocenti (charitable hospital) and head of the town council or Signoria. Perhaps unexpectedly for a merchant, Goro was also a prolific writer, whose surviving works range from the fairly public (an Istoria di Firenze / History of Florence that covers the years 1380–1404) to the intensely personal (his Memorie / Memoirs and Libro Segreto / Secret Book). And then there is La sfera / The Sphere, a poetic textbook designed to teach the next generation of Florentine merchants about natural phenomena, navigation, and the topography of the Mediterranean.

The authorship of La Sfera is, to some, a suspicious matter. Most of the manuscripts of La sfera that mention the work's author (at least 25 of the more than 150 manuscripts surviving) attribute it to Gregorio Dati. At least 6 other manuscripts, however, attribute the work to Goro's younger brother Leonardo, a high-ranking Dominican friar who served for some time as the order's Minister General. Because of this, some historians suggest that Goro Dati’s brother, Fra Leonardo Dati, was responsible for the text. Leonardo enjoyed extensive ecclesiastical education, whereas Goro concluded formal schooling at age thirteen. Some would assume that, as Goro seemingly lacked the education to write La Sfera, his more educated brother – who is credited as writing a portion of the text – wrote it himself.