5 Laws of Stupidity 

1) Always and inevitably everyone underestimates the number of stupid individuals in circulation. 
2) The probability that a certain person will be stupid is independent of any other characteristic of that person. 
3) A stupid person is a person who causes losses to another person or a group of persons while himself deriving no gain and even possibly incurring losses. 
4) Nonstupid people always underestimate the damaging power of stupid individuals
5) a stupid person is the most dangerous type of person

-Ilaria Periss