Believing the opposite of what Abdula says seems to work out well. I have discovered from the Shounen Jump raw providers that there won't be a Shounen Jump issue till the 18th. So I guess it's another week of arguing over crap again.

We've sure covered a lot in this thread: who's the strongest ninja (or is there one), who was the youngest Hokage, who's in who's genjutsu, etc. Now I guess we're on summoning.

Seeing as anything corporeal can apparently be summoned (weapons, logs, people, animals, talking animals, giant talking animals) I would imagine there is some ninja mechanism that allows one to access other dimensions for universally available storage and retrieval. Since the souls of the dead can be summoned it would follow that they must exist in some alternate dimension. So if a ninja knows the right dimension to look for and how to pull things out of other dimensions and into ours, then the only difference I see between a kunai and a soul is souls probably have a natural tendency to move to the soul dimension if not anchored to something that exists in the physical dimension.