Why does Coelho open with the modified myth of Narcissus?

The
shortof sets up much of the novel that follows. It does not tell the
reader anything about the plot of the book; instead, it briefly introduces us to some of its
central themes.

Unlike the traditional telling of the myth of Narcissus, this
version dwells more on the vanity of the lake as well as that of Narcissus himself. The
Alchemist expresses that this is a lovely version, perhaps indicating that he feels that vanity
is a virtue rather than a vice. This book is about finding love and worth in yourself, something
that the lake has done. In this way, the prologue subtly introduces the reader to the ideas that
are developed later on. These include transformative journeys, love, and fulfilling one's
personal legend.

This version of the myth of Narcissus also shows the idea
that individuals are not solitary beings. Everyone and everything is part of a greater unity,
and in many ways, we are all reflections of each otherjust as Narcissus's beauty and the
lake's...