Conversations with a Mirror

It would be such a fine thing,
If I knew, which of these were true,
The beliefs that I profess,
Or the image I see in you,

Clearly you are of fragments,
Much prevents reflection,
I watch the largest of pieces,
Eroding, to sand.

More pieces are added,
I am fearful of this puzzle,
Surviving, on just a dull light.
I beg you, tell me of truth and finding out.