## A Beginners Guide to Forcing

From: "andrew cooke" <andrew@...>

Date: Tue, 12 May 2009 06:35:03 -0400 (CLT)

http://www-math.mit.edu/~tchow/forcing.pdf

"In 1963, Paul Cohen stunned the mathematical world with his new technique
of forcing, which allowed him to solve several outstanding problems in set
theory at a single stroke. Perhaps most notably, he proved the
independence of the continuum hypothesis (CH) from the
Zermelo-Fraenkel-Choice (ZFC) axioms of set theory. The impact of Cohens
ideas on the practice of set theory, as well as on the philosophy of
mathematics, has been incalculable.

Curiously, though, despite the importance of Cohens work and the passage
of nearly ﬁfty years, forcing remains totally mysterious to the
vast majority of mathematicians, even those who know a little mathematical
logic."

Andrew