Negative numbers show up in nature all the time - they represent how much smaller a particular set of things is than what was defined as the 0 set. Sure, you ca

Negative numbers show up in nature all the time - they represent how much smaller a particular set of things is than what was defined as the 0 set. Sure, you can't have -5 rocks, but if you're counting how many more rocks you have than when you started counting gains and losses, -5 rocks is a reasonable quantity.