How we cite our quotes: All quotations are from Harry Potter and the Sorcerer's Stone.
Quote #4
DUMBLEDORE: It shows us nothing more or less than the deepest and most desperate desires of our hearts. Now you, Harry, who have never known family...you see them standing beside you. But remember this Harry. This mirror gives us neither knowledge nor truth. Men have wasted away in front of it. Even gone mad. That is why tomorrow it will be moved to a new home, and I must ask you not to go looking for it again. It does not do to dwell on dreams Harry, and forget to live.
The power of the mirror—and its danger—is that it distracts people form their duties, enticing them away from the unpleasant tasks that sometimes need doing if the world is to keep moving forward.