Most Helpful Girl
The nuclear weapons, because the people should not let someone just play with it and threaten human lives because they just felt like comparing buttons1
Most Helpful Guy
Think about what the implication would be. Racism is based on stupidity. Conflicts as well. Religion? Gone. Corruption? Those corrupt wouldn't be voted in. Violence too.
I see many suggestion in coments, and I am capable to track significant portion of them to stupidity.
I just cannot imagine how it would be done. :-D1