I am fully certain that I exist, body and soul, thoughts and memories, hopes and dreams. Finrod Felagund is not the offspring of mortal thought, of fantasy shaped into word and image, devoid of reality and lacking a history. I know that I live, as you know that you live. Indeed, I could rightly ask how you intend to prove that it is not you, not the people in this place, who are mere shadows of being in a dream I dream, a vision I see on the treshold of death? Who, indeed can tell if we do not all act our parts in a tale, told by a fool carried away by fancy?
Let me get this straight, You leave these quarters in the dead of night for a stroll across the Hogwarts grounds. You encounter a stray Dementor. It's rude enough to give you the cold shivers, so you appeal to its sense of decency and talk it into handing you its warm cloak by way of compensation?
— Remus Lupin
The same stars shine down on many places. But they won't tell you where to go if you don't have the lie of the land. How will you know there's no one near you?