For example, when a proton and an anti-proton collide, they cancel each other out. They become neutral. However when you multiply a positive and a negative number, you get a negative. You would need negative(electron) and a neutral(neutron) stay negative, but that would mean that our number system is missing an entire set of numbers. If our universe consists of Positives(protons) Negatives(electrons) and Neutrals(neutrons) then how can we expect to describe its behavior using a number system that only consists of Negatives and Neutrals? Should there be a third branch? Positive numbers, negatives, and neutral numbers? -1, 1, +1 all being different things? Can someone explain this to me?