Here's a question I'm asking myself in real life, but it is much more apparent in the world of TES because IRL, I'm a non-believer. Anyhow:
When a person, man or mer, or elven an animal or creature, dies, their soul goes either to a plane of Aetherius, to a plane of Oblivion, to the Darkness of Sithis, to the Soul Cairn or into a soul gem upon being captured (the latter of which being kinda the worst thing in my opinion). On rare occasions some souls stay within the Mundus as ghosts, albeit I don't quite understand what constitutes this last fate and where the mechanisms lie that bring about a ghost life on Nirn.
However, when new life is born, it has a soul (which can be taken) obviously. Now, here are my questions:
Whenever something dies, what circumstances need to be met to turn them into a ghost to walk Nirn?
To which plane go the souls of all non-human and non-merish creatures?
And, most importantly:
With every new birth, a soul unique to that person, and that person alone, must be created, correct? If so, do the aetherial planes of existence at some point burst from overpopulation? Because if there is a steady influx but no decreasing in souls, whichever place the souls go would surely fill up after a time. Am I wrong?
Which brings me to another question. By what process are souls created? If we take them as some form of energy, that energy needs to come from somewhere. Energy cannot be created, only relocated and somewhat influenced. It's a fundamental universal principle. So where does this energy cone from? Will that energy pool be depleted at some point? And what happens if it does? And if it doesn't, do souls expire after a time and get recycled in the outer cosmos?
So many questions!