The government in the United States consists of different parts and it is a very complicated system, as the result. Looking at the political-philosophical background of the American government may be helpful in explaining this novel and unique complexity. the philosophical bases, minded by the Founding Fathers when shaping the government in 1787 after the Revolution and composing the Constitution has been multifold, but mainly focusing on theories of Montesquieu (divided government), Thomas Hobbes (democracy), and John Lock (liberal democracy). These three weave tightly together to shape what we see now in the government of the United States. what this paper is going to search back in the historical philosophy, however, is analyzing not why the American government is ruled and maintained by the two party system, but to find out why it is divided almost always between the two parties (that is, why at least two main parties take control of parts of government, such that they make a balance in the control of power. As the word "divided" may suggest, the situation takes its roots from Montesquieu. That is, as Montesquieu argues, the control of power should be spread in different parts of an entity, i.e. government, so that the possibility of abuse of power is reduced to the least. Of course this is in line with other American basic political philosophies, democracy and liberal democracy, because it conforms to the principles of democracy that is against the power of the minority, or oligarchy. The divided government is now known in the American political terminology as the total system of "checks and balances". The system maintains the embodiment of the division of government in the form of binaries and/or vertical-horizontal divisions of power. It can be seen in federal, states and municipal governments. The other division of power is done vertically by cutting the federal government into three branches: executive (the President), legislative (Congress), and judicial (the courts). This way, each branch of power has a certain authority over the others.

going back to the main question "why does the government always consist of the two parties and not just one?", first it should be noted that two branches of executive and legislative are included in this regard _the judicial branch is excluded, because it is the President that chooses and appoints the judges for life, not the people. On the other hand, the President and members of the Congress are elected somehow directly by the people (not perfectly, due to the liberal democratic tradition in avoiding the minority dictatorship).

There are two main ideas for explaining this popular behavior in having the two branches each is in the hand of one party. The first says it is the Constitution-consciousness of the people that leads them to choose consciously to have two branches under the control of two parties. That is to say, it is an American mind to fear the oligarchy. In fact, if the affiliates of a party is powerful and multiple in number that it can decide to force one party into the White House, then the same amount of members exist for forcing the same party into the Congress. What makes voters not to do that is the mentioned fear of oligarchy, in spite of the fact that they may have accepted the principles of that party.

On the other hand, the second idea speaks of the situation as an accidental one. It proposes that the historical devotion of power of each branch to each of the two parties isn't something to be done consciously, but accidentally. For example, the affiliates of the party chosen for the executive branch are not so many to provide force to fill the Congress vocations as well.

The historical fact that during several elections of each branch held in the nation's history, the strange and interesting division has survived, although it has not been set as a rule in the Constitution, suggests the first idea as logical and acceptable.