Perhaps we put a period at the end of each sentence to curtail the fear of the dark that lies beyond that dark with its unknown duration before light returns. Outside, his warble silver and pocked as the half-moon impaled on branches, the mockingbird. On the other side of the windowpane, the sleeper hesitates.
Or maybe each perceived ending is a pivot that at best gives us pause; each dark mark a turning point. Silvery flashes of fish swerve up their natal river in a rush to the spawning ground as the luminous sleeper unconsciously beckons the pale sunlight of dawn, waving goodbye to festive stars and sweeping the darker slices of night through a gap in the clouds.