Sophrosyne an important topic for Plato. It is main subject of the dialogue "Charmides", wherein several definitions are proposed but no conclusion reached; however the dramatic context connotes moral purity and innocence. An etymological meaning of sophrosyne as "moral sanity" is proposed in "Cratylus" 411e. Plato's view of sophrosyne is related to Pythagorean "harmonia" ("Republic" 430e−432a, 442c) and closely linked with Plato’s tripartite division of the soul: "sophrosyne" is the harmonious moderation of the appetitive and spirited parts of the soul by the rational part (e.g., "Phaedrus" 237c−238e). For the Stoic, Zeno of Citium, "sophrosyne" is one of the four chief
Ancient Greek phonology at the end of a phrase. This usage was standardized in the Byzantine era, and is used in modern editions of Ancient Greek texts. Here it might mark a lowered version of a high-pitched syllable. Greek underwent many sound changes. Some occurred between Proto-Indo-European (PIE) and Proto-Greek (PGr), some between the Mycenaean Greek and Ancient Greek periods, which are separated by about 300 years (the Greek Dark Ages), and some during the Koine Greek period. Some sound changes occurred only in particular Ancient Greek dialects, not in others, and certain dialects, such as Boeotian and Laconian, underwent sound changes similar