1. People always underestimate the amount of idiots that their surround.
2. A probability that the person is stupid, doesn't depend on other qualities.
3. Fool is a person whose actions lead to losses to another person or group of people, and thus do not benefit the actor himself, or even turn around to harm him.
4. Non-fools always underestimate the destructive potential of fools. In particular, no-fools constantly forget that dealing with a fool at any time, anywhere and under any circumstances is to make a mistake that will cost in the future.
5. Fool is the most dangerous type of person.