the scabby and scrawny pierrot watches the fleshy , moneyed , self-important morsels and he cackles wondrously as he envisions the stealth of the approaching affliction which would liberate him from this interminable pain of diversion : rodents , mosquitoes , foaming cocker spaniels and mad roosters all scurrying through or flying amid the long grasses of the countryside , weaving through valleys , traversing swamps and rivers and wood toward the bustling metropolis , infecting all in their path with a fast-evolving , highly communicable pathogen which grows by migration and propagation in all directions and which devastates populations without ever stopping to consider its own status as a menace to humanity ( in fact , it knows not even of the existence of humanity , for it can not separate one nutrient-bearing organism from another , except perhaps by the subtleties of flavor , as to do so would require a discriminating sensitivity on the part of the microorganism : this might only occur within those predisposed to become connoisseurs of nutrient flavor and consistency over the course of their ultrashort life spans , which is a rare enough ability that one might be impelled to deem it a genetic abnormalitya mutation even ! but we shall not concern ourselves with such details just now ) .