Even with cash, you trust that the banks won't blacklist your serial numbers. With gold you trust that the world will not invent a new gold making method that w

Even with cash, you trust that the banks won't blacklist your serial numbers. With gold you trust that the world will not invent a new gold making method that will make it worthless (as happened with aluminum). A basic level of faith is required by any system, so that point is not valid.