‘If your time ain’t come, not even a doctor can kill you’ — so goes the proverb that best echoes the dilemma of an ageing humankind as we glimpse the harrowing vista of decrepitude to come: a panorama that first takes in the custard-stained wingback chairs of a soul-extinguishing care home, then yaws off nauseatingly to a vision of the demented and the drooling as they hobble into that good night.