How can you have a negative number of a physical object? I'm confused by the premise you've taken as a given. Is it possible for there to exist negative 11 apples in the world? Of course not, there are either some number of apples in the world, or there are 0 apples in the world. There cannot be negative numbers of physical objects.
Money is not a countable physical object like an apple. The economists have made sure that properly counted book keeping is circumvented whenever a big bank or a country runs out of money. If you got one apple at market and issued nine "iou one apple" notes, then that would be more like what seems to happen with money. Now which useless administrator told you that there would be a recession because your first six "iou one apple" notes were not enough so you must issue three more ? And what gets traded at market for iou notes?You might even get away with charging interest on all nine notes, and you'll be ok unless two noteholders return on the same day demanding to exchange their note for your apple.
In a village market which has one apple and nine "iou one apple notes", how many apples do they have in total?
An IOU for an apple is not a negative apple. A negative physical object logically cannot exist. You can owe someone an apple, but that doesn't mean there are negative 1 apples in the world because you cannot have less than zero apples. Furthermore, he said dollars (a specific physical object), not money (an abstract concept which can include negative values).
