On Benefits (De Beneficiis) is a first-century work by Lucius Annaeus Seneca. It forms part of a series of moral essays (or Dialogues) composed by Seneca and is essential reading for students of Stoicism. 
On Benefits is about the nature of relative benefits to persons fulfilling the role in social exchange of either giver or receiver. The subject in Seneca’s day might be thought of as social ethics, specifically Stoic ethics.