Read this passage from chapter 5 of The Prince.

And he who becomes master of a city accustomed to freedom and does not destroy it, may expect to be destroyed by it, for in rebellion it has always the watchword of liberty and its ancient privileges as a rallying point, which neither time nor benefits will ever cause it to forget. And whatever you may do or provide against, they never forget that name or their privileges unless they are disunited or dispersed, but at every chance they immediately rally to them, as Pisa after the hundred years she had been held in bondage by the Florentines.

How does text structure help Machiavelli convey his central idea?

Machiavelli identifies the problem of the Florentines holding Pisa after conquest and offers the solution of disuniting the city to keep it.
Machiavelli uses reasoning and an example as evidence in an argumentative structure to support his claim that a prince must destroy a city that is accustomed to freedom if he wants to hold it.
Machiavelli uses a compare-and-contrast structure to contrast a city that rebels with one that does not, thus supporting his central idea that a prince must destroy a city that is accustomed to freedom.
Machiavelli identifies freedom as a cause of rebellion in a conquered city and describes how the new prince can subdue the rebellion by destroying the city.