Originally Posted by

**DrSteve** I'm not sure what kind of book you're looking for. If you're looking for a book on how to do proofs, then I'm not sure if there are any good sources currently out there (someone correct me if I'm wrong). If you're looking for a book that has cardinality arguments, then there are lots of them. Any book on introductory set theory will have these arguments, and many analysis books will have some arguments like this in the introductory chapter. Unfortunately I haven't really found a set theory book that I particularly like, so when I teach set theory I use my own material. I'm not saying that the books out there don't have good material - only that I don't know of a book that I would personally base a whole course around.