Social contract theory is based on the idea of a contractual agreement between the individual and the state, under which the power of the sovereign is justified by a hypothetical social contract in which the people agree to obey in all matters in return for a guarantee of peace and security, which they lack in the warlike "state of nature" posited to exist before the contract is made.
Various philosophers have interpreted social contract theory. For example, John Locke believed that rulers also were obliged to protect private property and the right to freedom of thought, speech, and worship. Jean-Jacques Rousseau didn't believe that in the state of nature people are warlike, but are undeveloped in reasoning and morality. Therefore, by surrendering their individual freedom, they acquire political liberty and civil rights within a system of laws based on the "general will" of the governed.