In the 9th Book of Lucan’s “Bellum Civile”, the young Cato takes centre stage. With this, the epic also reaches the climax in its representation of Stoic ethics and interpretation of nature. In his commentary on verses 1-733 and three further essays on particular questions, Martin Seewald places particular emphasis on explicating Lucan’s paradoxical train of thought and the philosophical and scientific view of the world underlying the historical epic narrative.