Plato's notion of temperance, as elaborated in his
dialogues the Republic and the Laws, is far removed from conventional modern thinking on the subject. Platonic temperance is as much a public as a private virtue. lts manifold meanings include restraint, moderation, order, equilibrium, harmony, measure, selfcontrol and balance. Temperance in one or other of these senses underpins a number of key concepts which
lie at the heart of modern constitutional theory and practice. These are the social contract, the separation of powers in the state, the notion of a mixed constitution and the rule of law, among others. All of these notions are Platonic in origin, although they are often incorrectly
attributed to later writers. This article serves to identify and acknowledge Platonic temperance as the root of these key ideas, and the foundation of every sound constitution.