This wasn't an isolated quote from jefferson. "Let us provide in our constitution for its revision at stated periods. What these periods should be nature herself indicates. By the European tables of mortality, of the adults living at any one moment of time, a majority will be dead in about nineteen years. At the end of that period, then, a new majority is come into place; or, in other words, a new generation. Each generation is as independent as the one preceding, as that was of all which had gone before. It has then, like them, a right to choose for itself the form of government it believes most promotive of its own happiness; consequently, to accommodate to the circumstances in which it finds itself that received from its predecessors; and it is for the peace and good of mankind that a solemn opportunity of doing this every nineteen or twenty years should be provided by the constitution, so that it may be handed on with periodical repairs from generation to generation to the end of time, if anything human can so long endure." --Thomas Jefferson to Samuel Kercheval, 1816. ME 15:42