Giovanni (or Johannes) di Casali (or Casale) was a friar in the Franciscan Order, a natural philosopher and a theologian. He entered the order in Genoa and was lecturer in the Franciscan stadium at Assisi from 1335 to 1340. He subsequently was lector at Cambridge ca. 1340 to 1341, where he encountered the mathematical physics developed by the Oxford Calculators.
After he returned to Italy he taught at Bologna from 1346 to ca. 1352. About 1346 he wrote a treatise On the Velocity of the Motion of Alteration, which was subsequently printed in Venice in 1505. In it he presented a graphical analysis of the motion of accelerated bodies. His teachings in mathematical physics influenced scholars at the University of Padua and, it is believed, may have ultimately influenced the similar ideas presented over two centuries later by Galileo Galilei.[1]
He was appointed Papal Legate at the court of King Frederick of Sicily by Pope Gregory XI. He died about 1375.