The Dialogues were an important medium for the spreading of Greek philosophical theories to the Roman world and to subsequent ages. This selection is of complete, not excerpted, dialogues. The commentary concentrates on subject matter and the philosophical ideas informing the treatises, though help is also given where needed on grammatical and lexical points. The four chosen dialogues give a fair idea of the range of Seneca’s philosophical interests and of his didactic techniques. This is the first serious commentary in English on any of Seneca’s Dialogues since Duff (1915).