Giancarlo Livraghi presents a great essay on Walter Pitkin’s A Short Introduction to the History of Human Stupidity. It’s not a work with which I was familiar, but it’s a concept, and a history with which I have far too much experience!

Livraghi excerpts Pitkin’s description of Carlo Cipolla’s Five Laws of Stupidity:

• First Law
  We always underestimate the number of stupid people.
• Second Law
  The probability of a person being stupid is independent of any other characteristic of that person.
• Third (and Golden) Law
  A stupid person is someone who causes damage to another person, or a group of people, without any advantage accruing to himself (or herself) — or even with some resultant self-damage.
• Fourth Law
  Non-stupid people always underestimate the damaging power of stupid people. They constantly forget that at any moment, and in any circumstance, associating with stupid people invariably constitutes an expensive mistake.
• Fifth Law
  A stupid person is the most dangerous person in existence.

But to make things even better, Livraghi goes on to give us his own corollaries to these laws…

• In each of us there is a factor of stupidity, which is always larger than we suppose.
• When the stupidity of one person combines with the stupidity of others, the impact grows geometrically — i.e. by multiplication, not addition, of the individual stupidity factors.
• The combination of intelligence in different people has less impact than the combination of stupidity, because (Cipolla’s Fourth Law) “non-stupid people always underestimate the damaging power of stupid people.”

Those are the ones that are even more important, and more scary, than the original laws!