What is ordinarily known during deep sleep is the veil of ignorance which covers the Real. That is, the knowing faculty, the awareness is still present, but caught in the ignorance, the veiling, and knowing nothing else. The sage, however, carries into sleep the awareness he had in wakefulness. He may let it dim down to a glimmer, but it is always there.
-- Notebooks Category 25: World-Mind in Individual Mind > Chapter 2: Enlightenment Which Stays > # 180