Think Like a Freak, by Steven Levitt & Stephen Dubner

This is a shorter, faster to read and lighter version of the authors' wonderful Freakonomics text. Since everyone should read at least one of the authors' books and since this is so much lighter weight a read it might be the better suggestion for most folks. So read it!

Okay, you want to know why. Because it explains through clear writing and stories why one must test any important assumption - even when one believes the answer is well known. Which is, after all, the core of good science. And, as the authors demonstrate, good business as well.

Think Like a Freak: The Authors of Freakonomics Offer to Retrain Your Brain