This ghost was thinking:
do I exist in my own world
or do I only exist
in the human world?
if humans do not see me
do I exist,
or do I exist only
as they experience me?

And it thought so hard
it went up in a cloud of smoke -
****! - just like that
and ceased to be, from that moment

*Poor ghost,  it never found out the answer
And a human died and became a ghost
to take its place
and so it goes