Quintus Lucilius Balbus
Quintus Lucilius Balbus (fl. c. 100 BC) was a Roman Stoic philosopher, a pupil of Panaetius (the Stoic who brought the school to Rome). He is remembered chiefly as a character in Cicero’s dialogue De Natura Deorum (On the Nature of the Gods), where he is the expositor of the Stoic position on theology — the Stoic case for a rational, providential, divine cosmos — and Cicero represents his arguments as carrying considerable weight, comparing him to the best Greek philosophers.
Why he’s here
He’s a window onto Stoic theology and physics — the doctrine of a rational, god-pervaded Nature — preserved not through his own writings but as a voice in a dialogue, the way much ancient philosophy survives. Source: Wikipedia (T2, tertiary; a minor figure known via Cicero — thin record).