Hobbes defines Commonwealth as the multitude consolidated into one person, which he calls Leviathan. At this point, commonwealth can be also regarded as one person, of whose acts a great multitude, by mutual covenants one with another, have made themselves every one the author, to the end he may use the strength and means of them all, as he shall thing expedient, for their peace and common defense.
Despite the idea that the laws of nature presuppose that humans search for peace, the establishment of contract is the best method for its maintenance. However, the contracts cannot guarantee an absolute security of contracts. Therefore, Hobbes comes to an assumption that people should be controlled by a common power, a sovereign authority in order to make people obey the contract terms. The main weapon of sovereign is the threat of fear, as the insurance of a consistent and long-term accomplishment of the social contract.
According to Hobbes, sovereignty creates the connection between the contract and the artificial person, the one that is subjected to the rule of the government. The concept of an artificial person oppose to that of a natural person living under the laws of nature. Therefore, the former embodies the artificial creature called Leviathan. This metaphor applied to the explanation of state power that is created to provide the defense and peaceful existence for people.
It is not in vain that the philosopher compares Leviathan with the Biblical beast symbolizing the political power. His state, thus, is associated with strength, fear, and authority, since it must mortify the human nature and avert the recurrence of the natural state. The threats hidden in the world beyond Leviathan force people to avoid the civil wars and to uphold peaceful existence.
According to Hobbes, there are two approaches of organizing the commonwealth. The first one involves the application of force and the second one consisting in settling the agreement where the latter methods coincides with Hobbes’s explanation of transition of humans from natural conditions to the government status, which is achieved by the creation of the Leviathan. The sovereign authority established in a commonwealth implies three different types of organization: monarchy (to which Hobbes gives the priority), aristocracy, and democracy – three admissible versions of the Leviathan.