Erich Neumann’s conception of centroversion is his ‘typification’ of what Jung called ‘Mysterium Coniunctionis’ – it is Introversion and Extroversion unified in such a way that the result is the constellation of the Self.
Extroversion is, in this view, the archetypal ‘Hero’ – Tribal Chief, Leader; Will to Power over the world. And Introversion, the archetypal ‘Sage,’ Prophet, or Priest; Will to Sacrifice (one’s own Will, Life, Collectivity, etc – in service – to the Numinous/G-d, or the Jungian concept of the Collective Unconscious). One is in danger of getting trapped by the world of politics, war, materialism, etc.; The other is in danger of getting crushed by the onslaught of the archetypal flood of the Collective Unconscious.
Centroversion is the unification of the two into one totality; On a transpersonal level, this process applies to any ‘split off’ complex or archetype that has not yet been integrated into consciousness.
“Centroversion persistently strives to ensure that the ego shall not remain an organ of the unconscious, but shall become more and more the representative of wholeness. That is to say, the ego fights against the unconscious tendency that seeks to master it, and instead of allowing itself to be possessed, learns to keep its independence in relation to both inside and outside.”
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“Centroversion is the innate tendency of a whole to create unity within its parts and to synthesize their differences in unified systems.”
Erich Neumann, The Origins and History of Consciousness
In later development, once the Self has constellated, the hero (ego-consciousness) does willingly sacrifice itself to the Self, and become absorbed by it. In that way the conscious center moves from the ego (the hero) to the Self.