**Green's Theorem**: prov. [TMRC] For any story, in any group of people there will be at least
one person who has not heard the story. A refinement of the theorem states
that there will be *exactly* one person (if there were
more than one, it wouldn't be as bad to re-tell the story). [The name of
this theorem is a play on a fundamental theorem in
calculus. —ESR]