that, like a usufructuary, human beings have the right to use the earth for their own benefit and derive profit from it, but only to the extent that their actions do not impoverish the earth's bounty for future generations. It was, in other words, an expression both of rights (of the living) and obligations (of the living to those yet to be born). Jefferson's use of the word "living" is critical here: he meant that the usufructuaries of the world are those who are alive, not deceased past generations. This idea would profoundly influence Jefferson over the course of his life, and would lead to his acknowledgement that the Constitution of the United States would be revised by future generations, and was part of the reason that the Constitution includes a provision for its own amendment. Local variations France In France usufruct applies in inheritances. Under French law an indefeasible portion known as the forced estate passes to the deceased's surviving spouse and issue (with shares apportioned according to the number of children), with the rest of the estate – the free estate – free to dispose of by will. However, the surviving spouse may elect to distribute the forced estate as is, or convert it into a usufruct, or break up the estate into a distributable portion and a usufruct good for the children's lifetime. If a usufruct is chosen, a value is set for the usufruct interest for inheritance tax purposes and payable by the surviving spouse, on a sliding scale according to his/her age. The value of furniture and household items is calculated using a standard formula based on the appraised value of the estate's liquid and non-liquid assets, then the usufruct's value to the surviving spouse is subtracted, and finally the remaining balance is divided among the children on the death of the surviving spouse. This simplifies handling household items since the surviving spouse is free to maintain, replace or dispose of them as he/she wishes during his/her lifetime, with the monetary value of the items going to the children. Title to assets does not pass, and the usufruct disappears on death or at the end of a term of years. A usufruct is distinct from a trust or similar settlement. French law breaks with Roman law by construing a usufruct as not a servitude but rather a possessory interest. United States Louisiana Although the United