The Seba library treats Hegemonikon in 5 passages, across 4 authors (including Margaret Graver, Benveniste, Émile, Julian Jaynes).
In the library
5 passages
the Stoics posited what they called the 'directive faculty' or hegemonikon, a kind of clearing house to which sensations are referred and in which behaviors are initiated. This is the most specific terminological equivalent in Stoicism for our word 'mind.'
Graver defines the hegemonikon as the Stoics' central integrating faculty — their nearest analogue to 'mind' — responsible for receiving sensation and initiating action, located in the chest and networked throughout the body via pneumatic extensions.
I myself (a body), in my state of believing that p, am the cause to myself (again a body) of my judging p2 (a predicate).
Graver's technical notes on Stoic causation elaborate the causal structure of the hegemonikon's judgements, showing how the ruling part functions as the locus of assent and voluntary impulse within a deterministic chain.
Margaret Graver, Stoicism and Emotion, 2007supporting
what of the curious parallelism with Greek hēgeomai? The line of semantic development looks so similar that one is tempted to assume the same process for Greek.
Benveniste traces the semantic family of hēgeomai — the verbal root underlying hegemonikon — drawing a structural parallel with Latin ducere/ratio, situating the concept of directive leadership within a broader Indo-European logic of governance and calculation.
Benveniste, Émile, Indo European Language and Society, 1973supporting
noema has come to mean a composite of what we mean by thoughts, wishes, intents, etc... 'I know not what to do; my noemata are in two parts'
Jaynes's reconstruction of archaic Greek psychic vocabulary reveals a pre-unified, distributed conception of directive mental function that serves as a historical contrast to the integrated hegemonikon posited by later Stoic philosophy.
Julian Jaynes, The Origin of Consciousness in the Breakdown of the Bicameral Mind, 1976aside
The tendency to split means that parts of the psyche detach themselves from consciousness to such an extent that they not only appear foreign but lead an autonomous life of their own.
Jung's account of psychic splitting implicitly poses an inverse relationship to the hegemonikon's integrating function: where the Stoic directive faculty unifies, the autonomous complex fragments, raising the question of what governs when the ruling part fails.
Jung, Carl Gustav, The Structure and Dynamics of the Psyche, 1960aside