What is Plato's thesis statement in the Allegory of the Cave?

Analyzation of the Allegory of the Cave:
The prisoners represent unenlightened people who only believe what
thier physical senses tell them. The parapet hides the truth. The
figures of wood and stone represent that which is perceived as real,
but is not. The fire is a phantom. It leads the people to believe in
the shadow of reality. It merely shows a reflection of the truth, not
the actual substance of truth. This all has to do with Plato's concept
of "becoming". The prisoners are engaging in meaningless illusions.
Enlightenment (freeing onesself from the chains and seeing the reality
behind the wall) is the key to understanding reality.

Of course, this is just my take on it. Interesting reading, but as far
as a single thesis statement, beats me.

A step-by-step analysis
http://faculty.washington.edu/smcohen/320/cave.htm

as presented among the "Lecture Notes" of Marc Cohen
http://faculty.washington.edu/smcohen/320/320Lecture.html
http://faculty.washington.edu/smcohen/