C. Cassius Longinus to Cicero, written from Brundisium at the end of January 709 AUC — month-precision, end of January 45 BC (the Perseus dateline: Scr.\ Brundisi ex.\ m.\ Ian.\ a.\ 709 (45)). Cassius’s reply, and the only letter in the diptych cluster in his own voice. He is in the south, waiting on the outcome of the Spanish campaign — the news of Munda has not yet reached him — and he writes crisply, more directly than Cicero, with shorter clauses and less periodic build-up.

Section 1 takes up Cicero’s running joke and turns it on him: it is not the Epicurean spectra that make him feel Cicero’s presence as he writes, and in the next letter he threatens to return so many “countrified Stoics” that Cicero will think Catius the Insubrian was born at Athens. The central section is the philosophical core of the diptych: the Epicurean defence, in Cassius’s own hand, that pleasure [Greek: hēdonēn] and freedom from disturbance [Greek: ataraxian] are won precisely through virtue, justice, and the noble [Greek: tōi kalōi], and that Epicurus himself ratifies this with his sentence “there is no living pleasantly without living finely and justly.”

The third section turns to the death of Sulla — the public face of the Roman auction floor whom Cicero had reported in 15.17 — which Cassius shrugs off with grim wit: Caesar will not let him be missed, since he has condemned plenty who can be restored to take his place. The fourth turns dead serious: news of the Spains, the contrast between the “old and clement master” Caesar and a “new and cruel” one in Cnaeus Pompeius, and the open question — with which Cassius closes — whether Cicero will be reading the letter in an anxious or a free mind, since that will tell Cassius what to do. The closing one-liner, “if Caesar has won, expect me soon,” is the political calculation of the whole post-Pharsalus generation in one sentence.