It is often said not without a hint of self-satisfaction that roughly a third of our lives is made up of sleep.
That sleep be not only necessary for our functioning but also a biological need akin to eating and drinking is worthy of some philosophical attention.
(Good) sleep helps restore and regenerate us, boost our immune system, both physical and mental, and without it we would be seriously damaged in both mind and body within mere days of missing it.
While there are no doubt adequate scientific explanations behind our need for sleep, it is worth pondering the fact that nature has evidently designed us not to be always awake, alert and as having to pay constant attention to life's duties and worries.
Rather, through sleep, nature has ensured that we need that momentary, daily and several-hours-long escape from life's treadmill for, sleep failing, the treadmill would of necessity become a fatal Everest.
In other words, escape, as evidenced all the more by the phenomenon of dreaming, however much the latter is said to reflect our subconscious reality, is inbuilt in the human condition and life being the rough teacher that she can be, many need to escape her or, at the least, put her on hold, not only in their sleeping hours but also during much of their waking hours, whether it be through entertainment, mindful relaxation (where one takes a break from beings to commune with Being), entrenched routines, coping mechanisms, creativity, mind altering substances and so on.
As Thomas Eliot once put it,
"Humankind cannot bear too much reality"and even though sleep could be said to constitute a reality of its own, vital to such brain functions as memory and learning, it could also be seen as a gift given to us by way of nature to escape waking reality and understand that life's daily and habitual manifestations are but a part of the human story and psychological/existential make-up.
That is to say, the existence of sleep and the dreams that it conjures point us humans to that which is not, that which is not manifested in physical reality, that which does not exist in the visible realm, that which belongs only to the kingdom of the imagination, that which lies beneath five sense reality.
It was this insight that made Nietzsche argue in his work Human all too Human that the phenomena of sleep and dreaming are at the basis of the otherworldly, metaphysical, religious and even artistic preoccupations of mankind which none have to do with immediate biological survival but pertain to man's spiritual self and his need to create meaning.