When the duality of this ground is split into polarity, then we have not only the alternating plus and minus valences given to one half or the other, but we have a more fundamental negativity, that of the split archetype
Hillman argues that psychological pathology originates not in either pole individually but in the splitting of the unified senex-puer ground, constituting a disorder more fundamental than mere moral or developmental failure.
, Senex & Puer, 2015thesis