Noun
apatheia (uncountable)
English Wikipedia has an article on:apatheiaWikipedia
(philosophy) A state of mind in Stoic philosophy in which one is free from emotional disturbance; the freedom from all passions.
64. The proof of apatheia is had when the spirit begins to see its own light, when it remains in a state of tranquility in the presence of the images it has during sleep and when it maintains its calm as it beholds the affairs of life. Evagrius Ponticus