Thomas Hobbes

Thomas Hobbes is, if not the first, one of the first social contract theorists. He describes the formation of societies as we know them thus:

• Everyone is basically equal. Those who are deficient in some way, usually excell in some other way. There are a few exceptions to the rule, but on the whole, everyone is the same.
• But there are a limited number of resources, so people have to vie for them. Since everyone is the same, it is difficult to outdo others in the quest for resources. This creates fear.
• This fear is the characteristic of what Hobbes terms the 'State of Nature.' That state is one of constant war, a war of all against all. (People are not always trying to kill each other in this war - it's just the constant will to outdo others, by killing if need be, and the fear of being outdone or killed by others, that he means by war). Most people are not willing to accept that this is, in fact, the state of nature, so Hobbes offers this proof. Every time you go to sleep, you lock your doors, out of distrust, or fear, of someone coming to take what is one's own. The very fact that there is a need for police is testament to the malicious will of people.
• In this great war, it is difficult to secure resources, to survive. Since desire for survival is what causes this war in the first place, people came together, giving up all of their rights but a few. They do not give up their right to life, to false imprisonment, or to self-defense. People live by a rule similar to that in the Gospel: take only that much liberty against others as you would allow other to take against yourself.
• Once people come together under this rule, they have formed a social contract.

  Having come together in this manner, people were free to pursue other things than their immediate interests; society became industrialized and specialized, and now here we are. (This last bit is my own, but I'm sure Hobbes would agree).