As chief advisor to the emperor Nero, Lucius Annaeus Seneca was most influential in ancient Rome as a power behind the throne. His lasting fame derives from his writings on Stoic ideology, in which philosophy is a practical form of self-improvement rather than a matter of argument or wordplay. Seneca's letters to a young friend advise action rather than reflection, addressing the issues that confront every generation: how to achieve a good life; how to avoid corruption and self-indulgence; and how to live without fear of death. For several years of his turbulent life, Seneca was the guiding hand of the Roman Empire. His inspired reasoning derived mainly from the Stoic principles, which had originally been developed some centuries earlier in Athens. This selection of Seneca's letters shows him upholding the austere ethical ideals of Stoicism--the wisdom of the self-possessed person immune to overmastering emotions and life's setbacks--while valuing friendship and the courage of ordinary men, and criticizing the harsh treatment of slaves and the cruelties in the gladiatorial arena. The humanity and wit revealed in Seneca's interpretation of Stoicism is a moving and inspiring declaration of the dignity of the individual mind.