There's this town with two blacksmiths - one, a swordsmaker and the other, a shield maker. The swordsmaker's swords can slice through anything as a rule and the other guy's shields cannot be destroyed. Now they get cut up with each other for some reason and pit their wares against each other. What do you expect happens?
This problem is similar to a tango between two fundamental math rules.
1) Any number times zero is zero
2) And number divided by zero is infinity
So what happens when you take zero divided by zero? Well that depends on what form of zero you are using. 0/0 is impossible to solve for, however (X-2)/(X^2-4) where X=2 is not.
So in the sword and shield context, there are four possible answers:
1) the sword cuts the shield
2) the shield blocks the sword
3) any combination of the sword and shield both taking damage (or not taking damage).
4) a paradox
We don't have enough info to know the right answer, but I don't think we should say a universe that contains both can't exist, since ours is doing just fine!
Zero effect
