In theory, you could agree on a non-objective form of payment, as long as you agree on it. The point here is that the government must define what is and is not a government instrument for the payment of debts, again, as it applies in courts of law. The purpose of courts is to settle conflicts. Both parties can bring all the goodwill they want, but if they did not have a serious disagreement in principle they would not be in front of an artbitrator in the first place. That is why the assertion that courts are not supposed to interpret the law is poorly grounded. If the law were unambiguous, people of goodwill would never have any disagreements, at least not contractual ones. And pretty much that is true. We do not spend our lives in courtrooms over every misunderstanding because we really can work them out on our own. But what happens if you promise to pay with a herd of sheep and your herd dies? What would be equitable? You could offer Congressional medals, deeds for federal land, or the right to use a certain radio frequency. And if the other party finds something to agree on, then there is no problem. When a problem remains, you end up in court and there is found the requirement for a definition of legal tender.
(Edited by Michael Marotta on 4/06, 5:35pm)