Whoever is tired or exhausted seeks out sleep and welcomes it. One would think, however, that anyone reflecting soberly on sleep and its nature should rather fear it, since, the deeper we slip into sleep the closer we draw to a zero-point of consciousness, with nothing existing for us any more. Indeed, at such a point we no longer even exist for ourselves. Whoever is sleeping deep and dreamlessly has no longer any consciousness either of himself, of others, or of other things. If it is true that we are, in essence, just the consciousness produced by our brain then it must also be true that, in phases of sleep without consciousness, we cease to exist. But is non-existence not precisely that which is most generally feared? Praise of sleep, then, is always at the same time a highly telling praise of non-existence!
That temporary non-existence that goes hand in hand with deep and dreamless sleep is relevant not just to post-existential non-existence (sleep as the brother of death) but also to the mindfulness of pre-existential non-existence (sleep as the sister of never-having-been).