 The essentials of Epictetus’s thought derive from the early or foundational period of Stoicism, from the third-century writings of Zeno of Citium, Cleanthes, and Chrysippus. Treatises he mentions by title include Chrysippus’ On Choice, On Impulse, and On the Possibles, and he also mentions reading in works by Zeno, Cleanthes, and the second-century Stoics Antipater and Archedemus. Extant reports and fragments of these and other Stoic works offer many points of congruence with what we find in him.