When sleep the sentinels, ’tis the barbarian at the gate who strews their eyes with dreams. Then are they vanquished by the desert, leaving the gates free to turn noiselessly on their well-oiled hinges so that the city may be fecundated when she has become exhausted and needs the barbarian.
Sleeping sentry, you are the enemy’s advance guard. Already you are conquered, for your sleep comes of your belonging to the city no more, and being no longer firmly knotted to the city…And when I see you thus I tremble; for in you the empire, too, is sleeping, dying. You are but a symptom of its mortal sickness, for ill betides when it gives me sentries who fall asleep…
For if you no longer know that here a tree stands, then the roots, trunk, branches, leafage have no common measure. And you can you be faithful when an object for your fidelity is lacking? Well I know you would not sleep were you watching at the bedside of her you love. But that which should have been the object of your love is dispersed into fragments strewn at random, and you know it no more. Unloosed for you is the God-made knot that binds all things together.
–Antoine de St-Exupery, Citadelle