The night before this lecture, Neville recounts, he found himself in another, fully real state of consciousness where he met his old teacher Abdullah, his father, and his brother -- none of them still living in this world -- embracing and speaking with them as tangibly as with anyone in waking life. He uses the encounter to argue that the world he 'returned to' waking is no more objectively real than the one he had just left, since both are equally states of consciousness known only from within.