I. Political philosophy reveals how, in general, certain forms of government (e.g., monarchies, dictatorships) concentrate power and authority in the hands of a few in order to produce the best results. By adopting this results-oriented approach, they emphasize getting the right things done efficiently and preventing people in a country from adopting bad social policies. Other forms of government (e.g., democracies) assume certain fundamental rights (e.g., equality, justice, privacy) and evaluate laws and policies based on whether governmental actions respect these rights. These latter forms of government may not be as efficient as those governments based on producing results, but they pay more attention to the will of the people (even while acknowledging that the will of the people is occasionally mistaken).
Democracies are based on the assumptions that people are free and "autonomous"--that is, they are obligated to obey only those laws they have had a hand in formulating (autos means "self" and nomos means "law"). Autonomous individuals are people who have imposed laws on themselves rather than having laws imposed on them by someone else. In contrast to monarchies (where a ruler claims authority through divine right or heredity) and dictatorships (where might or power is the basis for political control), democracies have political legitimacy in virtue of the choice or agreement of their citizens to be governed by certain kinds of laws. That choice is expressed in terms of what is called the social contract.
II. Thomas Hobbes (1588-1679) characterizes the social contract as an agreement by the majority of a society to abide by the decisions of their duly recognized representative. Because individuals are constantly pursuing their own self-interests, they inevitably get into conflicts with one another, which is a threat to their survival. In order to survive at all, they recognize that the rational thing to do is to enter into an agreement (a "social contract") with one another to set up an overarching power that will regulate their behavior. Once made, the contract cannot be revoked: every citizen owes total allegiance to the government, and no resistance to authority is justified.
According to Hobbes, people are motivated only by self-interest and a desire for power. In the state of nature (prior to any rule by law) it is war of all against all. In the absence of law, there is no industry, security, or freedom from fear. Right and wrong, justice and injustice make no sense: such distinctions exist only in society and are founded by laws that are enforceable only by those in power (this position is sometimes called legal positivism). Justice is whatever the law (the powers that be) says is justice; there are no "unjust" laws.
In the state of nature we have a natural right to do whatever we can to survive. In scarce conditions, we will compete and live in fear of attack unless we appeal to reason. Thus it is rational--that is, a dictate of natural law--that in order to achieve peace, we should yield our rights as long as others will do likewise; this is the basis of the social contract. But we must be assured of compliance by others, so we yield our right to sovereignty to a central power (the Leviathan). Once I yield my right to decide what is right and wrong to the sovereign, I am no longer justified in revolting against the sovereign--unless, of course, I succeed in the revolt and retroactively declare (as the new authority) that my act was justified. Regardless of the social contract, though, I never give up my natural right to life (which is the basis for my entering into the social contract in the first place). The sovereign thus has no right to order me to take my own life, though he/she/it does have the right (i.e., the power) to take it if that is what is desired. As brutal as a state may turn out, it is always preferable to no state or government.
Objection: If concentrating power in the hands of a few is so rational, then why not rely directly on everyone's ability to act rationally instead of assuming that people are untrustworthy?
III. John Locke (1632-1704): In contrast to Hobbes (who believes that, in the state of nature, rational fear drives individuals to work with one another), Locke says that individuals in the state of nature are indifferent to one another (but decide that it would be easier on them to work together). For Hobbes civil society makes moral distinctions, whereas for Locke moral distinctions characterize social relations independent of civil relations: they are natural, God-given. Acting morally means acting in accord with nature, motivated by the threat of divine punishment/reward. For Locke, all human beings deserve to be treated equally and can justly be bound by civil laws (or government) only if they consent to such obligations.
Owning property (the product of one's labor), like control over one's own body, is a God-given right. As long as there is an abundance of goods that people can use without their spoiling, then they have a natural right to those goods. (This presupposes abundance, whereas Hobbes' philosophy assumes scarcity.) Money allows someone to accumulate more than he or she can use since it supposedly does not harm anyone else (even though this practice might result in some people not having the same opportunities as others).
In the state of nature, each person has the right to punish anyone who violates his rights. However, the state of nature lacks impartial judges, precise laws, and sufficient power to uphold the moral law. In order to identify and standardize violations and to regularize the proper meting out of punishment, we need government. The political state is justified only by consent of the people, who presume that the state will protect their natural rights of life, liberty, and property. The people freely agree through the social contract (either explicitly or tacitly) to abide by the laws that they or their elected representatives enact: in this way they are bound by civil law.
Tacit consent is given if a person chooses to live in a state or country and to benefit from the protection afforded by its laws. So no one has to make an explicit agreement to abide by the civil laws of a community in order still to be bound by them. If the government tries to take away the property of anyone in the society or to enslave the people, then the government can be justifiably overthrown. The ultimate function of government is to protect the moral state of human beings and their natural rights (especially private property).
Minor (historical) objections:
IV. Jean-Jacques Rousseau (1712-78): Humans are born free, autonomous, and naturally virtuous (even regarding self-love and compassion); but civil society perverts these feelings into selfishness, pride, and delight in the suffering of others. Being "civil" means becoming polite, lacking sincere motivation to care about doing what one naturally feels is the right thing. In civil society, moral distinctions are developed in order to handle conflicts (especially about the private property that is used to identify individuals). Government (political society) is needed to enforce the laws concerning private property, institutionalizing moral and political inequalities. However, civility does not have to promote insincerity: it can guide people through public education to resist the negative influences of society (e.g., valuing luxuries), and that is why people should form a social contract (to develop their natural virtues to even greater heights than would have been possible in the state of nature).
Children should be educated away from social influences, allowed to develop natural virtues through trial and error, sensations and feelings, not theories or abstractions. Only on this basis can a person develop sincerity in social relations (genuine morality rather than acting simply for show). The social contract is the agreement to abide by the general will, which is what I and all others living in a community will for ourselves (even when we disagree with particular legislation). In order to be free as a citizen, I will the law (for the common good); I am thus obligated to obey the law not because it is imposed externally but because it is self-imposed.