Introduction
Aka Manah, "Evil Mind" or "Evil Purpose" (later Akoman), is one of the six chief daevas of Zoroastrianism, opposed to the Amesha Spenta Vohu Manah, "Good Mind". Where Vohu Manah represents right thought and benevolent purpose, Aka Manah represents its direct opposite: corrupted, malicious thinking.
Corruption of thought
As the daeva paired against Vohu Manah, Aka Manah personifies evil intention and corrupted purpose at their source, in the mind itself, before they manifest in harmful words or deeds, making him, in the structure of Zoroastrian ethics, the demonic origin point of wrongdoing.
In the Shahnameh
In Ferdowsi's later epic the Shahnameh, Akoman appears in a more concrete, narrative role as a demon of Turan allied with or serving Afrasiyab's forces against the Iranian heroes, illustrating how the abstract theological daevas of the Avesta were given more folkloric, active roles as literal demonic adversaries in the later epic tradition.