Mirror of Erised

The Mirror of Erised is a mystical mirror discovered by Harry in a back corridor of Hogwarts School of Witchcraft and Wizardry in Harry Potter and the Philosopher's Stone. On it is inscribed, erised stra ehru oyt ube cafru oyt on wohsi — which, when reversed and correctly spaced, reads I show not your face but your heart's desire. According to Dumbledore, the Mirror "shows us nothing more or less than the deepest, most desperate desire of our hearts"; Harry, upon encountering the Mirror, can see his parents, as well as what appears to be a crowd of relatives; Ron sees himself as Head Boy and Quidditch Captain holding the Quidditch Cup (thus revealing his wish to be acknowledged in the shadow of his highly successful older brothers, as well as his more popular friend, Harry). Dumbledore, one of the only other characters to face the Mirror in the novel, claims to see himself holding a pair of socks, telling Harry that "one can never have enough socks", and lamenting that he did not receive any for Christmas, since people will insist on giving him books. If the claim was true, it might suggest that Dumbledore is, indeed, so content that he can wish for such small things. On the other hand, as the book is careful to inform us, Harry suspects he might merely have not wished to tell Harry. "It had been rather a personal question." In fact, in Harry Potter and the Deathly Hallows it is implied Dumbledore's vision would have been centered around his sister, Ariana.

The Mirror of Erised was the final protection given to the Philosopher's Stone. Dumbledore hid the Mirror and hid the Stone inside it, knowing that only a person who wanted to find the Stone, but not to use it, would be able to obtain the stone. Anyone else would see himself making an Elixir of Life or turning things to gold, rather than actually finding the Stone. Dumbledore tells Harry, "It was one of my more brilliant ideas, and between you and me, that's saying something."