This collection of 124 letters was written by Seneca near the end of his life, around 63–65 CE. Addressed to his friend Lucilius, the provincial governor of Sicily, they cover a wide range of philosophical topics with warmth, wit, and directness.
Part personal correspondence, part philosophical essay, the letters explore how to live well, face death, manage time, and cultivate wisdom. They remain among the most accessible introductions to Stoic thought.
"While we are postponing, life speeds by."
— Letters, 1