I think you have to answer the question why a written Constitution by thinking about the context that our Framers found themselves in. They had just had a successful revolution from the monarch in England. That was a big deal, and they'd won the war. And now that they'd won the war, they had to do something to establish a government in this new country that they had won the right to govern. The first try at this, the Articles of Confederation, had been a terrible failure, and had not worked at all to make a nation or preserve the peace that they were trying to establish. So a group of the leaders from all 13 colonies met in Philadelphia with the explicit goal of figuring out how they were going to govern themselves, of drafting a new Constitution. And the idea even of a Constitution was, I think, rather new, but they knew that they had to establish a new kind of government that was, in fact, a product of a revolution. And there was a lot of contention, but they were going for a unified objective, which was to establish a government that would work far into the future, a structure of government that would work far into the future. They knew they wanted a strong national government. They wanted to preserve the states. They wanted to make sure that the rights of the people as individuals were preserved. So having finally, and after a very difficult and very hot process in the Summer of 1787 in Philadelphia, they finally figured out what they wanted to do, and they memorialized it in a document. They had to make it written, because they had to figure out whether all of the Founders at the convention agreed to it, and then they had to submit it to the ratifiers in the various states. So it's a pretty obvious solution, when you're creating a brand new government, to write it down, and they were thinking far into the future to make a Constitution that would establish a government that would, in fact, last far into the future. Writing it down, memorialized it. And made it possible to enforce it. Not only to have it be submitted for ratification, but also to be enforced, down through the years. To organize the government and to give people the rights to which they were entitled for centuries to come.