Stoicism
The concept of equanimity was praised by at least two Roman Emperors. The Stoic Roman Emperor Marcus Aurelius' Meditations detail a philosophy of service and duty, describing how to find and preserve equanimity in the midst of conflict by following nature as a source of guidance and inspiration. His adoptive father Antoninus Pius' last word was uttered when the tribune of the night-watch came to ask him for the night's password — Pius decided upon "aequanimitas" (equanimity).
Read more about this topic: Equanimity