This story is so simple, too simple that could be a bit silly. But for me, this story is my understanding about inside and outside. Nothing in the world could exist independently, everything are relatively existed.
Which is to say, the worst thing is not not seeing it, but forgot to see. The outside of inside is outside, the outside of outside is still outside; The inside of inside is inside, the inside of outside is still inside. Then where the heck is inside and where is outside? They relatively exist.
A simple principle that suits everything we are living with. I might have made it too complicated, but you know what I mean.