CUP is giving away copies of Martin Gardner’s New Mathematical Library if you can solve a logic puzzle–any reader of this blog should be able to solve this one!
N.B. The rules that say: These books represent new editions of Gardner’s massive Scientific American corpus. Many people know these puzzles by heart. If you do, please encourage a Gardner neophyte to take a crack at it. Tell your local high school math club. [UPDATE]: If you know the puzzle, but pull off an awesome answer for it (see the next rule), by all means, enter.
Speaking of awesome answers to Gardner’s logic puzzles, which really are Smullyan logic puzzles (I think?), please put XOR’s Hammer into your feed readers! Michael O’Connor has set the bar very high for awesome answers to logic puzzles. And generally writes very interesting logic/math posts.