"The Basic Laws of Human Stupidity" ("Le leggi fondamentali della stupidità umana", 1976),[3][4]explores the controversial subject of stupidity.

These are Cipolla's five fundamental laws of stupidity:

Always and inevitably, everyone underestimates the number of stupid individuals in circulation.
The probability that a certain person (will) be stupid is independent of any other characteristic of that person.
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.
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.
A stupid person is the most dangerous type of person.
Corollary: a stupid person is more dangerous than a pillager

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