Broken Window Theory: Consider a building with a few broken windows. If the windows are not repaired, the tendency is for vandals to break a few more windows. Eventually, they may even break into the building, and if it's unoccupied, perhaps become squatters or light fires inside. Or consider a sidewalk. Some litter accumulates. Soon, more litter accumulates. Eventually, people even start leaving bags of trash from take-out restaurants there or even break into cars.
James Q. WilsonFour innate sentiments dispose people to a universal moral sense. These are sympathy, fairness, self-control and duty.
James Q. WilsonOne unrepaired broken window is a signal that no one cares, and so breaking more windows costs nothing.
James Q. Wilson