The combination of ethics and physics in Seneca’s Natural Questions has frequently puzzled scholars. Although a number of studies have attempted to reconcile the work’s ethical and physical parts, others maintain that there is no substantial connection between them. Both positions are problematic. The former glosses over the quite obvious ways in which these vivid accounts of vice are thematically at odds with the physics; the latter results in a bifurcation of the aims of the work. This study argues that (...) the incongruous character of these passages plays an integral part in the work’s overall goal: to defend the Stoic account of the ‘the good’. This account was under attack from Platonist rivals. The Stoics argue that the good is grounded ultimately in the wellbeing of the cosmos as a whole; Platonists maintain that conceptualising the good as such is impossible because, as empiricists, the Stoics can only account for a subjective understanding of the good, grounded first and foremost in the wellbeing of the body. Seneca’s engagement with this debate is indicated by the frequent allusions to Plato in the work, particularly the idea of ‘separating soul from body’. Seneca suggests that a carefully structured study of nature can achieve this ‘separation’. This process helps agents to overcome the subjective, body-focussed perspective that the Platonists associate with empiricism. Seneca thus demonstrates a therapeutic means through which an empiricist agent could come to conceive of the good as the Stoics envisage it. This same process of separation from one’s body, however, also provides an ideal opportunity to reflect critically on the objects that we tend to misidentify as goods. It is here that the moralising passages prove useful. These arresting accounts of vice serve to jar us into critical reflection on where we ground our understanding of the good. (shrink)