A brief selection from Economics in One Lesson, by Henry Hazlitt

Economics in One Lesson is a 218 page book by Henry Hazlitt; my wife has an early edition of it.  (http://www.amazon.com/Economics-One-Lesson-Shortest-Understand/dp/0517548232)   I've never read it, because I've never had to get past the initial premise, which is adapted from an essay by Frédéric Bastiat written in 1848: What Is Seen and What Is Not Seen (http://www.econlib.org/library/Bastiat/basEss1.html).  Also 218 pages doesn't strike me as one reasonably sized lesson.  (My wife found her copy and I flipped through it:  "The lesson" is only about 15 pages; the rest of the book is examples of bad policy.)

I would argue that a major goal of systems programming is finding the unseen behaviors in the code; the obvious stuff is easy.  The unseen stuff is hard.  I think you can replace "economist" with "programmer" and "policy" with "module" in the following.