 On Conversation deals with technical precepts about silence and speaking, recognizing the power of silence, the importance of contemplation, and the art of knowing when and to whom one should speak or keep silent. What little we have of On Gratitude deals with the gratitude which is properly given to one’s teacher and the relation between gratitude and friendship. This theme ties in with the share of money one receives in gratitude from one’s philosophical companions in exchange for philosophical discourses, which Philodemus in the treatise on household management from On Vices says is the best source of income for a philosopher (PHerc. 1424.23.23; for the treatise on household management, see now Tsouna 2012).