Knights and knaves puzzles
Knights and knaves logic puzzles were made popular by the logician and mathematician Raymond Smullyan. See http://en.wikipedia.org/wiki/Knights_and_Knaves. Here we have a total of 382 puzzles which get progressively more difficult. They were generated by a computer program written by Zachary Ernst. There are no answers provided, but you can always check if your friends agree with you!
Puzzle #1 out of 382
A very special island is inhabited only by knights and knaves. Knights always tell the truth, and knaves always lie.
Can you determine who is a knight and who is a knave?