Paul it looks like a scaled up thing that starts in the child. The first, if you will, "god" that the child experiences is the mother. She (usually) is the main source of survival, comfort and nuturance (including food) of course. As the mind develops with the maturation of the cerebral cortex, the child looks farther and farther afield. Finally at some point the whole issue of the meaning of life will arise in thoughtful people (almost all people). So the initial experience of incompletude or "inability" has to do with the very desparate matter (to the child) of food and comfort. Only as abstract reasoning develops does "self awareness" arise. (It is very hard to define what 'self awareness means so any help would be appreciated!) Along with self awareness comes the double edged sword of self comparison. That starts very young. The first born may be most at risk because he has no other "little ones" with whom he can compare his inabilities. The second born also looks ahead to the first born and may seek a conquest by "running harder" to overtake this "superior other" and the first born has this huge head start. So now we start to enter the arena of birth order influences.

So what I suggest is that is not so much a particular life situation that creates accentuated inferiority feelings, but rather how the child views the struggle. Some engage in the struggle with joyful delight. Some see it as an impossible obstacle, like a mountain towering over their tiny frame. The height of the mountain is in direct relationship to the depths of the "dark valley of despair".
Now as for the cosmic aspects we do gaze at the "splender of the Pliades" and the flame arc of the solar chariot of fire. Many of us feel small ... very very small in the scale of the cosmos. Many find comfort in the notion that the cosmos has resident within it a mind kindly disposed toward us in our frailness. This type of spirituality is in keeping with Adler's psychology, but not a necessary part save when Adler uses the term "Sub Specie aeternitatis" where it seems to be inferred. He makes no further comment about the "eternal" but at least he does not oppose such a notion like as does the American Psychiatric Association (or at least some of its members infer this is the position. I have not seen this in writing by them in fairness)
So yes, the initial inferiority feeling is a social one, but in very thoughtful people or in people like Jim Lovell who stood on the lunar surface at Tranquillity Base, it may extend into what has been called "cosmic loneliness". From this experience Jim became very interested in human spirituality at one time. I have no current information about his development and perhaps that is good because such a journey is a very personal thing.

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George Neeson M.D.