You understand sleep when you are awake, not while you are sleeping. You can see mistakes in arithmetic when your mind is working properly; while you are making them you cannot see them. Good people know about both bad and evil; bad people do not know about either.
C. S. Lewis (2003). “A Mind Awake: An Anthology of C. S. Lewis”, p.120, Houghton Mifflin Harcourt
