Anthropology
The Incas government was very in depth when managing the behavior of the Incas. Most of Inca rulers were great physiologist. They made it so that the Inca people were tired or didn't have the time to rebel, commit crimes, avoid the rules of the empire, avoid family, and avoid religion. Instead of making all Inca people work very hard they usually had festivals. Those times are normally the only time common workers get to get out of work.