People form societies when the obstacles faced in the state of nature become too arduous for any one person to overcome. Each person gives up his natural liberty - the freedom to do anything he desires - in exchange for the greater power of the entire community. Because everyone gives himself and all of his rights to the community, the conditions of the social contract are equal for all those involved. The association of many individuals with the same interests creates a collective body with its own life and will. This body is called the "state" when it is passive, and the "sovereign" when it is active.
Because the sovereign can be considered a private individual, there is no law that is obligatory to the people as a body. This would be the same as a private individual making a contract with himself. However, the sovereign cannot do anything that harms the social contract, because that would result in its dissolution. In addition, because it is formed by the association of private individuals, the sovereign cannot have interests that contradict with those of its members. The same is not true about the relations of subjects to the sovereign. Each person may have a private interest that interferes with or even harms the general will, but the social contract tacitly requires an individual to act in accordance with the common interest.
Rousseau claims that the transition from the state of nature to civil society creates a sense of justice that man previously lacked. Whereas man acted only upon his physical impulses in the state of nature, he feels a duty to his fellow men when placed in the context of society. Because of this moral change, man's mental faculties are developed, and his soul is elevated. This would be a very positive development if the demands of civil society were not so high. Each person gives himself - including all of his possessions - to the community when it is formed. The sovereign does not control the use of private property, but offers it better protection than any individual could give. This is because public possession is stronger and more easily accepted than private possession. The community legitimizes the right of the first occupant. It turns usurpation of natural resources into a true right, because all citizens acknowledge the legitimacy of private property.
Rousseau ends Book I by emphasizing the basis for every social system. Instead of destroying natural inequality, the social contract makes the physical differences found in the state of nature insignificant so that all men may be equal by convention and by right.
Rousseau argues that at some point, the obstacles confronted in the state of nature become too much for one person to handle. People form a community to combine the powers and talents of many individuals. However, this association presents the problem of how each person can retain his liberty while giving himself to the state. Rousseau establishes two conditions for a legitimate polity. The first is that no citizen can be in a relationship of personal dependence, and the second is that by obeying the law, a citizen only obeys himself. Throughout The Social Contract, Rousseau creates clauses for the social contract to ensure that these two conditions are met.
When people join together to form a community, they create a political body with a life and will of its own. By giving all of his rights to the sovereign and thus to all of its members, a citizen gives himself to no one in particular. He gains the equivalent of the freedom that he loses, and now has a greater amount of force to protect his life and property.
Although entering the social contract has many benefits, Rousseau acknowledges that people will often have interests that conflict with those of the sovereign. He asserts that anyone who does not obey the general will should be compelled to do so by the community, and thus "forced to be free." This statement has troubled many readers of Rousseau's work. Some have claimed that Rousseau supports tyranny and disregards individual rights because of this assertion. Although Rousseau's statement may seem paradoxical, it is important to emphasize that Rousseau distinguishes several types of freedom. Natural freedom is the ability to do anything one wants, and is found only in the state of nature. When a person enters the social contract, he gives up his natural freedom in exchange for civil freedom, and must obey the laws that he has helped to create. Rousseau clearly prefers civil freedom to natural freedom, and his concept that some people must be "forced to be free" is compatible with civil freedom.
This controversial statement can also be understood in another way. Rousseau believes that freedom and equality are inextricably linked: for each person to obey only himself, the laws must apply to everyone. A person who breaks the law creates an unequal relationship between himself and law-abiding citizens. In this situation, the state can use force to ensure equality among all its citizens.