This edition, the first modern one in English, introduces undergraduates and more advanced students to the therapeutic possibilities of Seneca’s Stoic philosophy. The short treatises De otio and De brevitate vitae balance each other by representing different but complementary aspects of Senecan philosophy: in De otio, one’s duty to the ‘active’ life, in De brevitate vitae, one’s duty to oneself in reclaiming life from the impositions made upon the self. The provocative Senecan message is to promote introspection in life, and to suggest the benefits of an inner existence of the personal. In addition to its literary and linguistic emphasis, this edition tries to advertize the means by which Seneca conveys the attractions of his therapeutic ‘philosophy’.