In the Empire, the basic unit of existence is the soul. A soul is not a metaphysical concept but a mind-machine matrix that allows functioning within the architectural tapestry. It is a symbiotic, synthetic organism created by the Emperor that merges itself into your consciousness, allowing for the possibility of backups, patches and edits. An ordinary soul may be no more than an uploaded version of the self, a utility account stapled to an otherwise normal life-form, tracking daily life and allowing simple immortality.
An augmented military soul is far more powerful, a battle-primed construction with info-warfare suites, expert-combat subroutines and Tzu-Clausewitz programming for instant high-precision tactical decisionmaking. The cost of such extensive modification is the demand it places on reserves of processing power. The more complicated the soul, the more taxing to computational resources. The greatest souls are artisan-crafted deities that drain the processing capacity of whole civilizations. Celestial tithes, stellar matrioshka brains and cyber-serf server farms maintain this hierarchy of processing capacity from unspeakable titans such as the The Emperor and The Dragon down to the lowliest soul. Below that is the pitiful automaton, treated as less than sapient unless ensouled.