A voluntary agreement between the rulers and the ruled. People agree to follow the rules so their natural rights are protected. When people don't follow the rules, they are punished. When the government fails to protect one's natural rights, the people rebel. This agreement is often times un-written. There are different social contracted based upon age, gender, location, and race.
Locke believes that people are naturally good and can work together.
Hobbes believes that people are naturally savage and don't work well together.
Respecting Elders: Today's Social Contract
Everybody knows it, but it's not written down. This can be considered as a social contract. There are certain rules that are followed in society in which children must be respectful to those who are older. Being polite and saying "please" and "thank you" is just one rule. Another is the idea of calling someone by "Mr.", "Mrs.", or "Ms.". it is a common courtesy that must be followed. The extremeness to this social contract can depend on location, race, gender, and age. For example, in China, kids are taught to have extreme respect towards their elders. In America, kids are supposed to have respect, but it is not to the same depth.
The government must protect your natural rights. There are three natural rights: Life, liberty, property.
Locke and Hobbes of The 20th Century
Kim Jong-un can be seen as one who follows the philosophy of Hobbes. He ruled as one in a dictatorship, the way Hobbes would've. He thinks all people must be controlled, they don't have a say.
Obama can be seen as one who follows the philosophy of Locke. He runs a country in which there is a democracy. People have a say because he believes we are naturally good. The government system is full of checks and balances, allowing not just one person to rule.