The previous post did a good job of explaining the issue of representation and the division it caused at the Constitutional Convention. At the same time, I think that two distinct elements motivated the framers in their assertions behind the need for the Constitution. The first would be that the Articles of Confederation, the government the Framers adopted after the Revolution, were simply not working. In the desire to keep the central government from infringing on the rights of sovereign states, nothing was being done from a national point of view. States were able to possess their own currency, and deny the existence of another state's. At the same time, each state operated as if they were their own nation, which made the new nation vulnerable to foreign threats. Finally, the difficulty in being able to initiate federal income taxes because each state could override it made resolving the federal debt impossible and also neutered the power of the national government. These intrinsic problems to the Articles were heightened by the emergence of Shays' Rebellion. A Massachusetts farmer that was upset at the financial condition of the new nation and the burden felt by farmers, Daniel Shays and a group of angry farmers stormed the steps of the Massachusetts state legislature, with violence ensuing. The terror caused by Shays' Rebellion, and the lack of an answer to the mounting economic and political problems caused by the Articles helped the framers conceive of the need of a new governing document, the Constitution.
Founders motives were to reshape and organize the government since the first form of government, the Articles of Confederation, was falling apart. They wanted to make sure the government brought the states together working as one, and paying taxes to a federal government in order to pay off debt from the Revolutionary War and to start building roads, schools, government buildings, etc. Also the motive was to protect the basic rights of the people, and balance the power between states and federal government, and between large and small states. In the end, there were many compromises made that created fairness and balance.
Their motives were to create a country in which justice, peace, equality, and freedoms could be enjoyed and preserved. I believe the founders were inspired by God to do what they did. They did it in such a way that the Constitution could stand the test of time, and be just as protective and binding on future generations as it was when they wrote it. It is all-inclusive and nothing has been left out. It is a set of values, principles, and idealogies that all Americans can be proud of and live up to.
Originally, representatives of the 13 states (Rhode Island did not participate) met in September 1786 in Annapolis, Maryland, to discuss revisions to the Articles of Confederation, but it soon became clear that most of them favored a complete rewriting of the Constitution. The representatives followed the lead of Virginia's James Madison, who proposed that the new nation should create a dual legislature--House and Senate--as well as a separate judiciary structure and an executive branch. The Virginia Plan also proposed that the legislative power would precede state laws.
Additionally, the proposed New Jersey plan would allow all states equal power despite their size or population. This plan was supported by the smaller states. A compromise was reached that would allow for an elected president; the Senate was designated as the states' affiliate, and the House was to serve as representatives of the people.
The issue of slavery, though discussed, was not decided, and the representatives instead postponed action for 20 years.