Professor of economic history at the University of California, BerkeleyCarlo M. Cipolla explained the five basic laws of human stupidity
Law 1: Always and inevitably everyone underestimates the number of stupid individuals in circulation.
Law 2: The probability that a certain person be stupid is independent of any other characteristic of that person.
Law 3. A stupid person is a person who causes losses to another person or to a group of persons while himself deriving no gain and even possibly incurring losses
Cipolla called this one the Golden Law of stupidity. A stupid person, according to the economist, is one who causes problems for others without any clear benefit to himself.
Law 4: Non-stupid people always underestimate the damaging power of stupid individuals. In particular non-stupid people constantly forget that at all times and places and under any circumstances to deal and/or associate with stupid people always turns out to be a costly mistake.
Law 5: A stupid person is the most dangerous type of person.
And its corollary:
A stupid person is more dangerous than a bandit.
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