Well, hm, i've never used this in actual game play but my kosmology could perhaps be described as reversed gnosticism (or perhaps rather neo-platonism, or hegelianism, or better still hinduism, blablabla...).
Humanity, as one supercounscioussnes divided in several lesser, is the only original basis for this universe. Reality (metropolis and the prison - in my version that is heaven, hell and the "normal" world) is our collective uncounscioussnes. The demiurge and astaroth are collective creations risen from the interactions of humanity (you could say that they are some sort of collective superego - demiurge controlling, astaroth punishing). Herbert Marcuse has proposed that the psychological diversion in ego and id (rational mind repressing emotions) is a social construct resulting from the taming of humanity that was necessary for taming nature. This is quite close to Freuds classic hypothesis that the superego is necessary in order to enable cooperation instead of a chaotic state of plunder and ravaging.
Pre-demiurge humanity has evolved from a singular uncounsciouss (when youre alone in the universe theres not much to be counsciouss about) superintelligence, through diversion (in order to achieve selfknowledge), to conflict among the individual splinterminds and therefore resulting in a need to inforce order through the creation of the demiurge-astaroth superego (or Leviathan if you asked Hobbes). Imprisonment was a desperat way to prevent the disolvement of the entire human superintellect. Now the powers of stability has been severly weakened (by the dynamic individual humans struggling for freedom through building cities etc) but will the splinterminds be able to achieve some sort of cooperative individualism or will they fall in to total war perhaps resulting in the return of the Demiurge or humanitys final dissolving in Achlyss?