Would don't always want always wish in your heart be the perfect moral for Harry Potter and the Philosopher's Stone?

Answer 1

There isn't just one moral in Harry Potter and the Philosopher's Stone, there are many. "Don't always want, always wish in your heart" refers mostly the to plot surrounding the Mirror of Erised, a mirror that shows your hearts deepest desire. Harry sees his parents alive and well in the mirror, something he can never have. He becomes obsessed with watching them until Dumbledore tells him the Mirror is moving, and then he cant's stop thinking about it. When discussing this, Dumbledore says that "it does not do to dwell on dreams and forget to live."

There is nothing wrong with wanting something, but it is important to be realistic.