The Fragment is an incomplete letter to the Emperor Zeno, preserved in a single Freising manuscript and unknown to scholars until its discovery by Frobenius Forster. The copyist extracted only the section dealing with the Alexandrian question, omitting the salutation and whatever preceded the transitional phrase Inter caetera et ad locum (“Among other matters, and to the point”). What survives is Simplicius’s direct response to the emperor’s proposal that Peter Mongus be made bishop of Alexandria.

The Fragment adds nothing doctrinally new to what Letter XVII had already said to Acacius about the same crisis. The canonical argument is the same: Peter is the accomplice of a parricide and a heretic; even if he now seeks amendment, he must pass through satisfactio before any question of promotion can arise; a man worthy of indulgence after repentance is worthy of indulgence, not of honor. The dismissal of Peter’s supporters as themselves separated from Catholic communion and therefore inadmissible as witnesses is the same principle of complicity that Gelasius would later develop at length in the Duo Sunt letter. What the Fragment adds is the addressee: this is not Simplicius writing to the patriarch who was supposed to be his intermediary, but Simplicius writing directly to the emperor who made the proposal. The refusal is delivered to the man who holds the coercive power, not merely to the man who was supposed to channel Roman directives.

The reader should attend to two features of the Fragment that the brevity of the text makes easy to overlook. First, the documentary reminder: “there is no doubt that I have often written requesting his expulsion from the city of Alexandria.” Simplicius is invoking the paper trail — Letters X, XI, XII, XIII, and XIV — as evidence that Rome’s position on Peter Mongus is not new, not improvised, and not subject to revision because the emperor has changed his mind. The archives hold the record, and the record is consistent. Second, the rhetorical question at the end: “who supports his promotion? I hear they are archimandrites and monks who have separated themselves from Catholic communion. Is their testimony to be approved?” The question answers itself: the supporters of Peter’s promotion are themselves heretics, and heretics cannot serve as witnesses to the fitness of a heretical candidate. The principle is juridical: testimony is admissible only from those who possess the standing to give it, and standing in ecclesiastical matters requires communion with the Catholic Church.

The Fragment breaks off with Finis — “End.” Whether this is the copyist’s notation that the manuscript ended here, or a scribal mark indicating the end of the extracted section, is unclear. What is clear is that the letter is incomplete: whatever directives Simplicius gave about John (the candidate the Egyptian synod had elected), whatever closing formula he used, and whatever dateline the letter bore are all lost. The letter belongs to the same period as Letters XVI and XVII (July 482).

The Henoticon would be issued later in 482, and Peter Mongus would be installed as patriarch of Alexandria under its terms — with Acacius’s support. Everything Simplicius had worked to prevent across five years of correspondence came to pass within months of this letter. The Fragment preserves Simplicius’s direct refusal to the emperor: he rejected Peter’s promotion, invoked the documentary record of his prior requests, and dismissed the testimony of those who supported it. The cooperative framework of 477–478 was over, and the conditions for the Acacian Schism — which would last thirty-five years and which Felix III would open by excommunicating Acacius in 484 — were now in place.