Why is sleep, which literally occurs daily on a planetary scale, so often taken for granted, and not only by most people but even by scientists? Perhaps because its essence, its key property, is to be elusive, out of sight? Sleep is about being invisible, private, not attracting attention, our secret, vegetal life, a pure existence outside the maelstrom of interaction. Not surprisingly, echoing Aristotle’s view of it as ‘a privation of waking’, sleep is typically defined by what it is not, rather than what it is. It is not moving, not acting, not responding, being disconnected from the world, doing nothing, at least from the observer’s perspective. When any organism sleeps, it takes a kind of leave of absence: it stops interacting with the environment, withdraws from action, and also gives space to others. Sleep, nightmares apart, is the only time when we are at peace with ourselves, forgetting pain and suffering, and the world outside, as we leave it alone to respite from us. A blessing for both the sleeping individual and for planet Earth.
— Read on aeon.co/essays/two-billion-humans-are-doing-something-bizarre-right-now-sleeping