Camus

"Till four in the morning one is seldom doing anything and at that hour, even if the night has been a night of betrayal, one is asleep. Yes, everyone sleeps at that hour, and this is reassuring, since the great longing of an unquiet heart is to possess constantly and consciously the loved one, or, failing that, to be able to plunge the loved one, when a time of absence intervenes, into a dreamless sleep timed to last unbroken until the day they meet again." Camus, from The Plague.