The Mirror of Erised shows us nothing more or less than the deepest, most desperate desire of our hearts. The happiest person in the whole world would look in the mirror and see a reflection of exactly the way he or she is. Inscribed across the top of the frame is the following text: Erised stra ehru oyt ube cafru oyt on wohsi Reversing the inscription and rearranging the spaces produces: I show not your face but your heart's desire It can be very very dangerous though, so be careful.
