There is nothing like a doorbell to precipitate the potential into the kinetic. When you stand outside a door and push the button, something has to happen. Someone must respond; whatever is inside must be revealed. Questions will be answered, uncertainties or mysteries dispelled. A situation will be started on its way through unknown complications to an unpredictable conclusion. The answer to your summons may be to a rush of tearful welcome, a suspicious eye at the crack of the door, a shot through the hardwood, anything. Any pushing of any doorbell button is as rich in dramatic possibility as that scene in Chekhov when, just as the Zemstvo doctor's only child dies if diphtheria and the doctor's wife drops to her knees beside the bed and the doctor, smelling of carbolic, takes an uncertain step backward, the bell sounds sharply in the hall.