LitCharts assigns a color and icon to each theme in The Social Contract, which you can use to track the themes throughout the work.
Human Freedom and Society
Sovereignty, Citizenship, and Direct Democracy
Government and the Separation of Powers
National Longevity and Moral Virtue
Summary
Analysis
When people get together and form a state, they create a common will and begin implementing it. Their goals are simple but lasting: “peace, unity, equality,” and of course happiness. Since the people are of one mind in an ideal state, there would be no need to deliberate about new laws: everyone would recognize and do what is in the common interest. But most states are not so successful, and in them “particular interests” start to gain more power and “the common interest becomes corrupted and meets opposition.” Eventually, the state becomes “empty and illusory,” everyone recognizes that the political system is broken, and “the general will is silenced”—but it does not disappear; it is only overwhelmed by people’s particular wills and ignored by those people.
Having implicitly noted the conflict between private interests and the public good throughout Book 3, Rousseau now explicitly describes this conflict and admits that it is inevitable, because every citizen would always put their own self-interest first. In turn, people will only choose to pursue the best interests of the whole nation if civic culture and institutions convince them that their own status and wellbeing depend on their investment in the community. While it is possible to reach the general will simply by averaging out the private interests of all the individuals who make up the sovereign (as Rousseau noted in Book 2, Chapter 3), if people are not committed to finding the general will, they will likely just form political parties (which are like body politics within the body politic) and discount the interests of their opponents. This splintering is precisely why the general will gets ignored and states die, and it is not completely preventable. It can, however, be reduced and delayed if citizens are encouraged to value their place in public life.