The present project is a reading of the three Platonic dialogues Euthyphro, Laches and Charmides and the four texts Of Honour and Disgrace, Correcting Doctrines, Undoing Blindness and Correcting Appellations from the late Warring States collection Xunzi ??, associated with the thinker Xun Kuang ??. The project focuses on the use of definitions by the two thinkers. Both engage in ethical theorising. The project is a contribution to the current widespread interest in comparative ethics. It is set apart from much work in the field by the formal or argumentative angle adopted. The claim to be made by the project is that the uses these thinkers make of definitions are best understood in light of how they understand the nature of moral disagreement, and that by tracing the different current models of disagreement in both thinkers the use made of definitions can be made clear. The comparison gains traction by understanding moral disagreement in terms of the Socratic question: How should one live? This perspective, on the one hand, connects their thoughts intimately with their political and social contexts; on the other, makes comparison of the uses of this importamt argumentative tool possible by interpreting it as being deployed against different answers to the same question. Definitions can for example be used to dissolve disagreements by making clear that different things are being talked about.
