Arhopala sophrosyne is a butterfly in the family Lycaenidae. The men fight over which of their wives best exemplified sophrosyne. Sophrosyne is an important topic for Plato. An etymological meaning of sophrosyne as "moral sanity" is proposed in "Cratylus" 411e. Charmides first suggests that sophrosyne is a kind of quietness (159b). Sophrosyne, according to St. Thomas Aquinas, is the fourth and final cardinal virtue. For the Stoic, Zeno of Citium, "sophrosyne" is one of the four chief virtues.