 Epicurus’ conception of the role of justice was more central to his eudaimonism perhaps than its counterpart in Plato and Aristotle, but that reflects in part his distinctive understanding of eudaimonia, or happiness. For Epicurus this consisted in ataraxia — tranquility, or freedom from disturbance. Given that the good life is the life without disturbance, justice plays a key instrumental role. One might, Epicurus thinks, withdraw entirely from human society to avoid disturbance, but the alternative is to live socially under terms which secure the avoidance of disturbance. This is the structure of the ideal Epicurean community, in which each forbears aggression (Armstrong 1997, Thrasher 2013). Justice is a matter of keeping agreements generally, and in particular the agreement not to harm or transgress social norms.