This is the scene where Jack is in the Agincourt Hotel, and he is fighting the last of the knights. He is describing his surroundings as he is flipping through a vast amount of worlds, and describes seeing a great many people who "were beautiful but doomed, and so ghosts always seem to the living." This is very similar to when Roland is climbing the Dark Tower in the last book, and sees on each level different people in a similar fashion, both those he had known along the journey and those he had not, and were described as almost ghost like.