From Wikipedia, so take it with a grain of salt!
In moral and political philosophy, the social contract is a theory or model that originated during the Age of Enlightenment and usually concerns the legitimacy of the authority of the state over the individual.
Social contract arguments typically are that individuals have consented, either explicitly or tacitly, to surrender some of their freedoms and submit to the authority (of the ruler, or to the decision of a majority) in exchange for protection of their remaining rights or maintenance of the social order. The relation between natural and legal rights is often a topic of social contract theory.
The starting point for most social contract theories is an examination of the human condition absent of any political order (termed the “state of nature” by Thomas Hobbes). In this condition, individuals’ actions are bound only by their personal power and conscience. From this shared starting point, social contract theorists seek to demonstrate why rational individuals would voluntarily consent to give up their natural freedom to obtain the benefits of political order.
The central assertion that social contract theory approaches is that law and political order are not natural, but human creations. The social contract and the political order it creates are simply the means towards an end—the benefit of the individuals involved—and legitimate only to the extent that they fulfill their part of the agreement. Hobbes argued that government is not a party to the original contract and citizens are not obligated to submit to the government when it is too weak to act effectively to suppress factionalism and civil unrest.
According to other social contract theorists, when the government fails to secure their natural rights (Locke) or satisfy the best interests of society (called the “general will” by Rousseau), citizens can withdraw their obligation to obey or change the leadership through elections or other means including, when necessary, violence. Locke believed that natural rights were inalienable, and therefore the rule of God superseded government authority, while Rousseau believed that democracy (majority-rule) was the best way to ensure welfare while maintaining individual freedom under the rule of law. The Lockean concept of the social contract was invoked in the United States Declaration of Independence.
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