I always feel that the best puzzles are the simplest ones. This puzzle is one of the simplest and most elegant I have ever heard. There are no tricks involved here.
“A blind person is given a normal deck of 52 cards. They are told that exactly 10 of the cards are facing up, all the rest are facing down. How can the blind person divide the cards into 2 separate piles, with each pile consisting of an equal number of cards facing up?”