“Why does it make us uneasy
to know that the map
is within the map
and the thousand and one nights
are within The 1001 Nights?
Why does it disquiet us to know that
Don Quixote is the reader of the Quixote,
and Hamlet is a spectator in Hamlet?
I believe I have found the answer:
those inversions suggest that if the characters in a story
can be readers or spectators, then we,
their readers or spectators,
can be fictitious.
In 1833 Carlyle observed that universal history
is an infinite sacred book that all men write
and read and try to understand,
and in which they too are written.”

-Jorge Luis Borges,
Partial Magic of the Quixote, p. 234-35