We are only as strong as we are united, as weak as we are divided.
— J. K. Rowling

Of course it is happening inside your head, Harry, but why on earth should that mean that it is not real?
J. K. Rowling dumbledore quote

Dumbledore will only leave from Hogwarts when there are none loyal to him!
— J. K. Rowling

It was, he thought, the difference between being dragged into the arena to face a battle to the death and walking into the arena with your head held high. Some people, perhaps, would say that there was little to choose between the two ways, but Dumbledore knew - and so do I, thought Harry, with a rush of fierce pride, and so did my parents - that there was all the difference in the world.
— J. K. Rowling

I took a wrong turn on the way to the bathroom and found myself in a beautifully proportioned room I had never seen before, containing a really rather magnificent collection of chamberpots. When I went back to investigate more closely, I discovered that the room had vanished. But I must keep an eye out for it. Possibly it is only accessible at five thirty in the morning. Or it may only appear at the quarter moon - or when the seeker has an exceptionally full bladder.
— J. K. Rowling