Is stupidity rising? Are we witnessing an alarming proliferation of irrationality and an exuberance of ignorance? 

Stupidity seems a concern to a growing group of scholars. Last month alone two arXiv papers (here and here) appeared that both refer to a 35 year old essay by the Italian economic historian Carlo Cipolla entitled "The Basic Laws of Human Stupidity". In this humorous yet thought-provocative treatise Cipolla warns against the power of stupidity. Three of Cipolla laws of stupidity I reproduce here. The first provides a definition for stupidity, and the latter two highlight the abundance and the effectiveness of stupidity:
"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."
"Always and inevitably everyone underestimates the number of stupid individuals in circulation."
"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."
Cipolla describes stupid people as an unstructured, yet powerful group. He argues that when you suffer due to the actions of others, it is likely not due to malevolent actions, but rather due to stupid actions:
"Our daily life is mostly, made of cases in which we lose money and/or time and/or energy and/or appetite, cheerfulness and good health because of the improbable action of some preposterous creature who has nothing to gain and indeed gains nothing from causing us embarrassment, difficulties or harm. Nobody knows, understands or can possibly explain why that preposterous creature does what he does. In fact there is no explanation - or better there is only one explanation: the person in question is stupid."
Since Cipolla's essay appeared in 1976, several authors have rediscovered his findings. In particular, Hanlon's razor
"Never attribute to malice that which can be adequately explained by stupidity"
published by Robert Hanlon four years following Cipolla's essay, can be interpreted as a corollary to the basic laws of stupidity listed above. 

A Darwinian Enigma

Although the above thoughts on the effects of stupidity might seem compelling, they do leave us with an enigma ignored by Cipolla and his followers: how come stupidity abounds? Should stupidity not have been eliminated long ago by the process of natural selection?

At first sight, stupidity is a characteristic that is expected in natural selection processes to suffer and to become extinct. After all, stupid persons by definition act in ways that tend to yield no gain to them. Place a stupid person in a competitive environment of non-stupid persons, and the stupid person will likely come out as the loser, and certainly not as the fittest.

How then can stupidity survive and flourish?

Let me attempt to provide a satisfactory answer to this question. I do not claim to have reached a definitive answer, but the mechanism I propose, if not fully explaining the survival of stupidity, at least contributes to it. Moreover, and as often is the case, the route towards the answer is interesting in itself. It will bring us from poker strategy to the limits of applicability of game theory. 

Key feature of stupidity is that its power lies in its abundance. One stupid person is helpless, a herd of stupid persons can be invincible. Place a smart individual in a group of stupid persons and you will witness the smart person succumb to stupidity. In an environment infested by stupidity 'being the smartest' does not equate to 'being the fittest'. 

To get a grip on the mechanism behind the effectiveness of abundant stupidity, we go back to 1997. In that year Andy Morton, a poker-playing molecular biologist posted a poker strategy article on the internet that can be summarized as:
"beware of the power of stupidity"
a catchphrase that equally well summarizes Cipolla's findings.
In his poker strategy posting Morton effectively demonstrates that also in zero-sum games like poker the damaging effect of a stupidity can extend well beyond the person acting stupidly. Morton describes a realistic poker scenario in which you can only hope that your opponents make the right play, as a stupid move by one of them will hurt you. What happens in this scenario is that the stupid move by one of your opponents harms the opponent's monetary expectation as well as yours, and causes an opposing (positive) effect on the expectations of the other players. Note that this 'Morton effect' (a stupid move of your opponent hurting you) can not be present in a two-player zero-sum game. For the Morton effect to occur in a zero-sum game, you need to be facing multiple opponents.

The Double Morton

We are now ready to introduce the next and final step in our quest to explain the abundance of stupidity: the double Morton. The mechanism behind the double Morton is easy to understand based on the Morton effect in a multi-player games.

Suppose you are playing a three-player game against Alice and Bob. Assuming this game to be enriched by Morton effects, Alice will have the choice of a stupid move that will make herself and you suffer while Bob will profit. But so can Bob: a stupid move is available to him that will cause himself and you to suffer while Alice will profit. 

What will happen if both players will make such a stupid move? 

The net effect will be that you suffer while Alice and Bob will gain. This double Morton effect is what makes stupidity disproportionally effective in groups infested by stupidity. It provides stupidity with a positive feedback loop that results in stupidity breeding stupidity.  Morton's example is specific to poker situations, but the Morton effect as well as the double Morton are abundant in many multi-player games. Constructing a simple example game that highlights the power of the double Morton is rather straightforward.

The Tennis Dilemma

You and two of your tennis friends are independently offered the use of a tennis court. Each of you has to decide on the spot and without any opportunity to negotiate or communicate which offer to take: 45 minutes of tennis at court A, or 60 minutes at court B. If all three of you opt for the same court, you can all play but you have to share the court amongst the three of you, so that each of you will play 2/3rd of the total time available. If one of you selects a court different from the choice of the two others, (s)he is alone and can not play any tennis, while the other two each have the court of their choice available to play for the full time allotted.

Which tennis court do you choose?
Do I hear 'B'? Good! With tennis court 'B' available for a longer period and all other things being equal, non-stupid persons will select option 'B'. Assuming that your two friends make the same rational choice, you will each enjoy 40 minutes of tennis. 

"What is the dilemma?", you might ask, "there is only one reasonable choice! I know option 'B' is best, and so do the two others. I would never select 'A', that would leave me empty handed and give them the full 60 minutes of tennis."

If these thoughts crossed your mind, you have fallen victim of Cipolla's law on non-stupid people underestimating the damaging power of stupid individuals. Let's see why this is the case.

As we have seen, you will be doing well with your rational choice for option 'B' as long as at least one of the two others behaves rational as well. 

But what if both others behave stupidly and select court 'A'? This changes things dramatically. You end up alone at court 'B' which gives you zero minutes of play, while the two others each enjoy 45 minutes of tennis.

How stupid is that?

Imagine the discussion afterwards. "You should have selected the other court" you shout at your friends when they have finished their game. 

"Why would we?" is the calm reply. 

"Choosing 'A' is a really stupid move!" you burst out, "choice 'B' gives much more playing time!"

"How much time would we have received if we had selected option 'B'? 

"We would each have had 40 minutes!"

"Ha! We have played for 45 minutes. I think you are stupid!"

Loud laughter surrounds you while your 'stupid' tennis friends walk to the tennis bar, leaving you speechless.

Stupid2 = Smart

The above tennis dilemma makes it trivially clear that two stupid choices, neither of them directed towards optimizing ones gains, can generate an unbeatable outcome. Two 'stupids' can make a 'smart'. This, however, is a destructive 'smart' as it effectively reduces the total benefit to the group (in this case by reducing the total player-time from 120 to 90 minutes). 

Note that according to Cipollo's definition a player who selected 'A' is individually guilty of being stupid. Would this player have changed his choice from 'A' to 'B', he would have increased his time at the tennis court from 45 to 60 minutes and the total time of the two others also from 45 to 60 minutes. So by not selecting choice 'B' this player reduced not only his time on the tennis court by 15 minutes, but also the time of the others by the same amount. However, the two players who selected 'A' are collectively not stupid at all. With you opting for the rational choice 'B', there is no way they jointly could have pocketed more playing time.

We see here the 'double Morton' in full swing: a critical mass of stupidity result in an unbeatable destructive force. This occurs at the poker table, but equally well in real life.

The double Morton puts limits to the applicability of game theory, as this theory is based on the premise of rational behavior. In groups in which false beliefs like 'choice A is best' become popular, game theory is rendered of limited use. That does not mean a rational person will be a helpless victim of the irrationality surrounding her. She might work out that if at least 64% of the population adheres to the false belief 'A is best', the optimal response is to move with the majority and also select 'A'. So in a population dominated by stupidity, rational persons are forced to behave stupidly. 

The following scenario is therefore entirely possible: three rational individuals participate in the tennis dilemma without knowing any of the other players. All three, however, do know that in the population they live in choice 'A' is made more than 64% of the time. All three of them therefore make the rational choice of option 'A'. When confronted with the outcome, all three think "pfew, good that I anticipated the irrational behavior of the other two!". Interestingly, it could very well be that in this population irrationality is a thing of the past: all individuals act rationally by responding to hard statistics. Stupid behavior is not synonymous to irrational behavior.

It should by now be clear that the double Morton provides a mechanism for stupidity to be abundant. Provided double Mortons occur in the everyday survival game we refer to as 'living your life', stupidity, when abundant, will have a tendency to stay abundant.

Victim of Stupidity

We all repeatedly fall victim of the Morton effect. Someone acts stupidly thereby hurting not only himself but also you. The fact that this can happen in nonzero-sum games is rather trivial. Morton made it clear that this scenario extends to multiplayer zero-sum games.

But even the person who knows best the power of stupidity remains vulnerable in the presence of such.

When he disclosed his theory back in 1997 Andy Morton was aged 33. He tragically died a year later. The cause of his premature death? Andy fell victim of the Morton effect and paid the ultimate price for someone else acting stupidly. Andy was riding his motorcycle when a woman in a pickup truck approaching Andy pulled out into oncoming traffic and hit him head on, killing Andy instantly.
More Hammock Physicist articles on game theory:  
- The Art Of Acting Rational
- You're So Predictable!
- You, Retaliator!