Analysis of A Reversed Underneath

A reversed underneath means the top should surely be,
The bottom where the bottom was that you surely see;
And the bottom means the bottom was but not could surely be,
For the bottom is the top where the top could no longer be;

To bring the sides in play would truly be confusing,
For the sides could be where the bottom was, though really refusing;
This would mean the sides would have to be where top used to be,
And this would mean all screwed up, as you can surely see.