why the sun, an interesting question.
while it is true that the sun is connected to various principles as mentioned before, i think it depends on something else.
but before i will get to this we must indeed ask "what is the sun?".
im not going to get back to the sciency part, i dont know anything about it anyway.
what does the sun symbolise:
to me the sun is a form of lifebringer (altho it isn't entirely true, only in the way it works here the way it does now)
because of it we have a chance of living, from the tiny plant to the big beasts, we all live in the foodchain, depending on one another, if there was no sun, our ecology would change and life as we know it would not be (makes you question if we would have a chance in a sunless world, taking the freezing part out of the equation)
the sun has been pictured many times as (a product of) a god, for the effect it has on our every day life, there is no way to go around its importance.
why did i say it is not a lifebringer, the sun is not an element of good or light, only how it works now to our benefit would make us say that. (if we would look at other planets we would see that the sun would make life inthere impossible)
someone mentioned a possible connection between the sun and heatgain.
it is possible, the sun is an emmitor or various rays, which are in fact nothing else but various forms of energy.
and when do you get heat? when you use your energy: fighting, saccing, binding a creature to you ,...
do we absorb the sun's energy? up to a certain level, yes i believe so.
the question would be then, what would happen during nighttime, would we still gain heat or not.
but more important, why is there a sun?
because we are limited by our imagination.
it is the only thing we know (of a natural form) that is able to do what it does.
the more important question question would be, if not a sun, what else?
or what if there was no sun?
would we be in endless night then, or sunless day,or...
about the inner sun:
i do believe the sun is a symbol of the centre, the core.
as i described earlier, the sun is not a sign of "light" or its conotations.
yes, the inner sun is neutral as stated before (here or the other topic with Mur's answer)
much depends on where the sun is, or in this case whose sun it is.
as the sun is mandatory to our survival, our inner sun is equally important to us..
it can be compared with our soul,however not entirely correct.
our inner sun can also be a expressed as self knowledge, (and acceptance)
when we embrace our inner sun we are free
these are my thoughts and are most likely completely off the mark.