<em>Epistulae Morales ad Lucilium</em> (Moral Letters to Lucilius)

The Moral Letters are Seneca's most influential work: 124 letters addressed to Lucilius Junior, a Roman procurator in Sicily, written during the last years of Seneca's life (c. 63–65 CE) as Nero's character darkened and Seneca's influence waned. The letters cover the full range of Stoic ethics — the dichotomy of control, the taxonomy of goods, the governance of time, the contempt for wealth, the preparation for death — but their force comes from their specificity. Each letter addresses a concrete situation: Lucilius's anxiety about a legal proceeding, his grief over a friend's death, his uncertainty about retirement, his fear of poverty. Seneca's counsel is not abstract. It is tactical, biographical, tested. The letters assume an intelligent interlocutor capable of philosophical seriousness and adjust the truth to the situation rather than the situation to a comforting lie. The literary form — philosophical counsel delivered through personal correspondence — became the model for Marcus Aurelius's Meditations