Stoicism: An influential philosophy in ancient Greece and in the Roman world that emphasized a person’s control over the emotions. Founded by Zeno of Citium (334-262 B.C.; not to be confused with Zeno the Eleatic, famous for his paradoxes), Stoicism evolved over time, with three periods usually distinguished: Early Stoicism, Middle Stoicism and Roman Stoicism. Most surviving Stoic writings come from the last period, with the slave Epictetus and the emperor Marcus Aurelius being two of the most famous Stoics. Stoicism was characterized by a conviction that the universe has a rational structure and that whatever happens does so with necessity. True virtue requires an acceptance of external events; the virtuous person lives in accordance with the reason that shapes the universe and gains contentment by an attitude of indifference to the external goods and evils that most people desire and fear.
Evans, C. Stephen (2010-04-28). Pocket Dictionary of Apologetics & Philosophy of Religion (pp. 110-111). Intervarsity Press. Kindle Edition.