Letters from a Stoic is a collection of 124 letters written by the Roman Stoic philosopher Seneca the Younger towards the end of his life (around 65 AD). The letters are addressed to his friend Lucilius Junior, then the procurator of Sicily, but they were clearly written with a wider audience in mind. They serve as a practical and accessible guide to the philosophy of Stoicism, offering moral counsel and reflections on how to live a virtuous, tranquil, and meaningful life.