Here are the Five Laws of Stupidity according to Carlo Cipolla: 

First Law 

     We always underestimate the number of stupid people. 

This is not as obvious as it sounds, says Cipolla, because: 

   a.people we had thought to be rational and intelligent suddenly turn out to be unquestionably stupid; 

     and 

   b.day after day we are hampered in whatever we do by stupid people who invariably turn up in the least appropriate places. 

He also observes that it is impossible to set a percentage, because any number we choose will be too small. 

Second Law 

     The probability of a person being stupid is independent of any other characteristic of that person. 

If you study the frequency of stupidity in the people who come to clean up classrooms after hours, you find that it is much higher than you
expected. You assume that this is related to their lower level of education, or to the fact that non-stupid people have better chances of
obtaining good jobs. But when you analyze students or University professors (or, I would add, computer programmers) the distribution is
exactly the same. 

Militant feminists may be incensed, says Cipolla, but the stupidity factor is the same in both genders (or as many genders, or sexes, as you
may choose to consider). No difference in the sigma factor, as Cipolla calls it, can be found by race, color, ethnic heritage, education, etcetera. 

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. 

(We shall come back to this, because it is the pivotal concept of the Cipolla Theory.) 

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. 

That (I would say) suggests that non-stupid people are a bit stupid -- but I shall get back to this point at the end. 

Fifth Law 

     A stupid person is the most dangerous person in existence. 

This is probably the most widely understood of the Laws, if only because it is common knowledge that intelligent people, hostile as they might
be, are predictable, while stupid people are not. Moreover, its basic corollary: 

     A stupid person is more dangerous than a bandit 

leads us to the heart of the Cipolla Theory. There are four types of people, he says, depending on their behavior in a transaction: 

Professor Cipolla uses a matrix that looks like this: 

                    Y

                    |
                    |
                    |
        H           | +         I
                    |
                    |
                    |
                    |
------------------- O -------------------  X
        -           |           +
                    |
                    |
                    |
        S           | -         B
                    |
                    |
                    |

The "X" axis measures the advantage gained from one's actions. 

The "Y" axis measures the advantage gained by another person (or group). 

Clearly, people in the "I" area are intelligent, people in the "B" area are bandits, people in the "H" area are hapless, and people in the "S" area
are stupid. 

It is also quite clear that, depending on where they fall in this matrix, people have a greater or lesser degree of stupidity, intelligence, banditism,
etc. One can develop quite a variety of combinations, such as smart bandits or stupid bandits, depending on the benefit-damage ratio. (In this,
Cipolla observes, the amount of damage is to be measured from the perspective of the victim, not the bandit, which makes most thieves and
criminals quite stupid.) 

I guess that from here on each of us can use this matrix to study stupidity and elaborate the application of the Cipolla Theory in all its many
possible variations. 

But that is not quite the end of the story. 

                    Y

                    |
.                   |
   .         Hi     |
      .             | +         I
         .          |
            .       |
        Hs     .    |
                  . |
------------------- O -------------------  X
        -           |  .       +
                    |     .
                    |        .     Bi
                    |           .
        S           | -            .
                    |    Bs           .
                    |                    .
                    |                       M

If we draw a diagonal line across the matrix, we find that everything on the upper right side of this line generates an improvement to the overall
balance of the system, while events (and people) on the other side cause a deterioration. 
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