(2) As to legal tender, it seems to me that the public mind has been sadly confused under the régime of paper money. Money is any commodity which is set apart by common consent to serve as a medium of exchange. If it is a commodity, it will exchange by the laws of value, and will therefore serve to measure value. It must therefore be a commodity, an object of desire requiring onerous exertion to get it. In theory, it may be any commodity. The question as to what commodity is a question of convenience--that one which will answer the purpose best. Through a long period of experiments we have come to use gold or silver, simply because we found them the best. Convenience here gave rise to custom, and money of gold or silver owes its existence to custom entirely, and not to law at all. Law has only in very few instances even selected that one of the two metals which should be used. Even that has come about through custom. Law, therefore, here as elsewhere where it has been beneficent and not arbitrary, has followed custom, recognized it, ratified it, and given it sanctions. (1) A legal tender law, therefore, where customary money is used, simply declares that the parties to a contract shall not vex each other by arbitrarily departing from the custom. The creditor shall not demand, and the debtor shall not offer, out of spite or malice, anything but the customary money of the nation. Such a legal tender law has no significance whatever. No one thinks of it or speaks of it or takes it into account, unless he be one of those whose idle malice it prevents. (2) A legal tender law is used where a subsidiary token currency is employed as a part of the system, to prevent debtors from using it in payment, and to prevent the system from bringing about a depreciation of the money. In this case it is part of the device for using a token currency, and is open to no objection. It would check the debtor when he meant to perpetrate a wrong. It would not enable him to do one.