Free will in antiquity
In Plato's Gorgias (and in the Protagoras 345c4-e6), Socrates argues that no one does wrong willingly, one of the most famous doctrines to be associated with him. When framed in modern (Western) terms, the implication is that it is ignorance, rather that free individual agency, that is responsible for morally wrong actions.
Epicurus
Epicurus was first to assert human freedom as a result of the fundamental indeterminism in the motion of atoms. This has led some philosophers to think that, for Epicurus, free will was "caused directly by chance". In his "On the Nature of Things", Lucretius appears to suggest this in the best-known passage on Epicurus' position. In his "Letter to Menoeceus", however, Epicurus follows Aristotle and clearly identifies "three" possible causes: "some things happen of necessity, others by chance, others through our own agency." Aristotle said some things "depend on us" ("eph'hemin"). Epicurus agreed, and said it is to these last things that praise and blame naturally attach. For Epicurus, the "swerve" of the atoms simply defeated determinism to leave room for autonomous agency.