But ancient Indian philosophers — writing thousands of years before Socrates — thought it was crucial to distinguish modes of consciousness within the range of what, in the Western tradition, we call unconsciousness. Dreaming, lucid dreaming, deep and dreamless sleep, and so-called pure awareness — the awareness that is always present beneath or behind waking, dreaming, and peaceful, dreamless sleep — are examples of such modes. I won't pursue these in any detail here. My present point is more general.