[1] His Italian given name was Tolomeo, variuosly spelled "Tolomeus", "Tholomeus", "Thollomeus", "Ptolomeus" and "Ptholomeus" in the Latin documents of the time.
He was distinguished for piety, and his intense application to study, for which reasons he won the respect and warm friendship of Thomas Aquinas.
Jacques Échard affirms that he was the close friend and often the confessor of John XXII, who appointed him Bishop of Torcello, March 15, 1318.
A conflict with the Patriarch of Grado concerning the appointment of an abbess of Sant'Antonio di Torcello [it] led to his excommunication in 1321, and exile.
[5] The best-known work of Ptolemy is his Annales (1061–1303), finished about 1307, wherein are recorded in terse sentences the chief events of this period.
Ptolomaei are no longer considered original works by separate authors, but are extracts from the Historia Ecclesiastica Nova by some unknown compiler who lived after the death of Ptolemy.
A committed republican, Ptolemy was central to developing a theory for the practices of Northern Italian republicanism and was the first writer to compare Aristotle's examples of mixed constitutions - Sparta, Crete, and Carthage - with the Roman Republic, the ancient Hebrew polity, the Church, and medieval communes, yet he remained a staunch defender of the absolute secular and spiritual monarchy of the pope.