Cassandra has moved. Ugo Bardi publishes now on a new site called "The Seneca Effect."

Monday, July 27, 2015

Hardin's "tragedy of the commons" explained with a practical example: a tourist trap in Florence

Image by James Good

Garrett Hardin's idea of "The Tragedy of the Commons" has become well known, but not always really understood. In my case, I can say that I have big troubles in having my students grasping its mechanism; that is the interplay of individual advantage versus public goods; the basic factor that leads to what we call "overexploitation."

Perhaps the problem lies in the fact that Hardin used the example of sheep and pastures to explain the reasons of the tragedy, but that's rather unfamiliar to my students (as well as to most of us). For instance, many of my students don't seem to be able to grasp the concept of "overgrazing", that is the fact that grass doesn't regrow if it is grazed too much. Besides, the pastures that Hardin was considering never experienced the "tragedy"; they were well managed and well regulated, specifically in order to avoid it.

So, let me propose a different example for the mechanism of overexploitation, based on a real event that happened to me. Maybe it can explain the concept better.

Just a few days ago I was literally kidnapped inside an underground parking in Florence because I had lost my entrance ticket, with the employees of the place insisting that they won't let me out unless I was willing to shell out 237 euros for about two hours of parking (!!).

I described the experience in detail in a post in Italian, that you may machine translate if you are really interested. The gist of the story, anyway, is that I found myself caught in a trap mainly designed to siphon out some money out of the pockets of the hapless foreign tourist passing by. In my case, I was able to negotiate my release and avoid paying the exorbitant surcharge. But, put yourself in the shoes of someone who doesn't speak the local language, doesn't know what are his/her rights, is in a hurry; then the best strategy is to pay and be over with it. Although, after such an experience, most tourists will probably swear that they won't ever again set foot in this hateful city.

Now, despite the rather nasty circumstances, what I have described is nothing more than an economic transaction. But, here, there doesn't seem to hold the conventional view that demand and offer are always the same and, at the same time, "right". What happens, instead, is the perverse mechanism of Hardin's tragedy taking hold of the situation.

Let's quantify: by forcing a tourist to pay 237 Eur, the management of the parking lot gains the difference between the normal parking rate (say, 4 euros) and the surcharge; a net gain of 233 Euros. At the same time, the fact that the tourist mugged in this way will never come back to Florence means a loss in terms of hotel rooms, meals, various purchases and more. Considering that the enraged tourist will also discourage friends and relatives from coming to Florence, the overall loss is surely of the order of several thousand euros. The transaction, therefore, turns out to be a net loss for everyone involved.

But here comes Hardin's tragedy. The loss of thousands of euros is spread over several thousands of operators in the tourism industry and for each one it is so small to be nearly invisible. Instead, the monetary gain of 233 euros is well visible for those who pocketed it. There follows that almost everyone, as an individual or a single firm, gains in overcharging tourists. That's what generates what we call a "tourist trap," a common occurrence everywhere tourists go.

It is the same mechanism of Hardin's original example, with the tourists in the role of grass and the tourism operators in the role of shepherds. In Hardin's example, overgrazing leads to the destruction of the resource (grass). In the case I was describing, tourists in Florence have not been destroyed, yet, but they are constantly overcharged, overcrowded, and overexploited in various ways. It is not so obvious that they will continue to flock to a place where they are so badly mistreated and so often.

I know what you are thinking, that Florence will always be Florence. True, but visiting Florence is, in the end, the result of the fact that it is fashionable to do it. And fashions change over time. Years ago, it was fashionable to buy overpriced and oversized cars, and manufacturers thought they could overexploit their customers at will. For a while, yes; then look at what has happened to Detroit.

The final point of this discussion is to note how difficult it is for human beings to manage well the resources they exploit. The overexploitation phenomenon lurks almost everywhere and it is extremely difficult to stop it, because it generates a cascade of economic gains that overcome the (usually feeble) attempts of the authorities to regulate the use of the resource. It is true for tourism, but also for minerals, for fish, for agriculture, whatever you have that generates an economic return sufficiently large to make it possible to reinvest a fraction of it to increase the exploitation rate. We haven't found a way to avoid the tragedy in modern times and chances are that we never will, at least as long as we reason in terms of maximizing individual profits and we keep believing that doing that optimizes the exploitation of the system. Maybe it does, but at the cost of destroying it.


  1. Nice story. I remember a similar experience, thoug by far not as crass. It was one hour before my train to Germany departed, in a bar on Piazza della Signoria, when a glass of lemonsoda cost more than what I had left in lire (back then), which would have been good for four or five glasses everywhere else. The waiters had mercy with me and were contented with getting what they reasonably could.

    In spite of this, remarkably, Florence is in fashion since approximately 500 years, and no decline in sight. :-) The grass (tourists) just keeps regrowing.

    More to the point, there is one aspect of human behaviour, which is made to deal with Hardings situation, and it is called ethics. It had been boiled down by Immanuel Kant to his categorical imperative of ethics, which more or less reads: Let the maxim of your actions be so, that it could become a general law. This is interestingly a kind of stability criterion for a mass of individual actions (or the maxims thereof).

    In the same direction go things like customs, which develop in a society over many centuries, and have the principle of not destroying the basis of life in them. (Not always, unfortunately.)

  2. Ha! I was just thinking about this subject today -but on the base of my experience last week of being stopped by the police near Pisa. As you know, here it Italy is seems to be rare that police will pull you over for actually violating road rules, but instead prefer a random-stop system so that they can comb through your paperwork for any citable violations. The police in Pisa badly wanted to fine me 400 Euros for not having a translated driver's license but I would not accept such a fine because the US has an accord with Italy that states that US licenses are valid in Italy (at least such an accord used to exist, I should probably update my info). After several calls to other officers and to the office, the officers could not refute my claim and begrudgingly let me go with my pocketbook unharmed but I noticed how they saw tourists as cash-fat revenue and just today I was musing about how many other persons the typical (car-renting) tourist would in time dissuade from visiting Italy after receiving such a painful fine for not having "eyes color: brown" officially translated.
    I unscientifically estimated about 10, after the story would have been retold as a second-hand anecdote.

    I find the Detroit comparison brilliant.


    1. The destruction of the tourist resource seems to be more widespread than I thought. Maybe the comparison with Detroit may have been indeed appropriate!

  3. So based on your story, how are the garage parking lot owners able to use profits for the next round of exploitation? More advertising for their parking lot? Bigger guns? The rape/exploitation (tragedy) of the commons is a feature of competitive systems, which is why cooperative systems are far more common in well developed systems. Using the terminology tragedy of the commons is more interesting in my estimation, it implies something wrong with the commons. It places the emphasis of the problem on the wrong place in my opinion. I had the luxury of talking to an early U.S. Historian about ideas surrounding its revolution from Britain being an anti corporate movement and he informed me that idea was popular in the 1930s after the Great Depression, which is a time when many ecologists began talking about cooperation instead of competition. It is amazing to me how our ideologies and terminologies fit so closely to the current societal paradigms. Put another way there is nothing tragic about the commons, only the competitive paradigm we are choosing to use them within.

    1. Well, the garage owners themselves aren't going to build another garage with what they steal from a few hapless tourists. But sum up the ill gotten gains of all the operators in the sector and I think you get a good fraction of the capital "fuel" that makes the tourism industry grow.

    2. BTW, the city government wants to enlarge the existing airport to make it possible for large planes to land directly in Florence. The system can exist only if it grows. And overexploitation is a consequence

    3. Perhaps we could go back to the days of the British Empire ascendant, when English tourists when on continental journeys were reputed to shout at railway station staff and occasionally poke them with umbrellas because the staff did not speak English? Err... I am joking, but faced with such highway robbery as you describe even I might be tempted to use my umbrella. Seriously, pound sterling is not quite what it was back in the day, even if this summer for a moment it magically produces more euros to pay exorbitant bills.

  4. "The final point of this discussion is to note how difficult it is for human beings to manage well the resources they exploit. The overexploitation phenomenon lurks almost everywhere and it is extremely difficult to stop it ..."

    This is why, upon reflection, it has always seemed far easier to me to reduce human population than it is to transform human behavior for the better. Most human societies throughout history have been exploitative, destructive of natural resources and often were unsustainable in other ways as well. If there were not so many people, pollution problems would be manageable, the extractive industries would not be destroying the landscape (tar sands, strip mining, deforestation, etc.), resources of all kinds would last longer, species would not be going extinct at such an alarming rate, global warming would be much slower, etc. Garret Hardin understand these simple facts as well.

    There are just a handful of nations around today that seem to be making a reasonable effort at becoming sustainable. Off the top of my head they include Norway, Sweden, Finland, Switzerland, Costa Rica and possibly New Zealand. If you're generous you could include a few more. What do these nations have in common? All of them are either small in terms of area (Switzerland, Denmark, Costa Rica) or they have relatively low population densities (Norway, Sweden, Finland). Should we be surprised?

    1. In my opinion, it is very difficult to manage a top-down control of the population; true, it would probably solve at its roots the overexploitation problem, but how to implement it? I have a post in the pipeline that discusses this issue.

    2. Well, China tried it with some success and Hardin applauded forced sterilization, though had four children himself - aren't people funny...

    3. I got the impression, that family planning campaigns got pretty much out of fashion, after having been used extensively in the 70s/80s. I wonder why. Lack of necessity certainly not. Lack of success may be. Or, due to the process called "green revolution", because of p e r c e i v e d lack of necessity.

  5. A good story, but you should be careful using the Tragedy of the Commons concept. It's a misconception of how true commons actually work, for access to them is controlled by people who use them. This has to be the case because many/most commons have remained intact for hundreds of years. If you as an outsider turn up with a flock of sheep to a true commons, you will be rapidly ejected, often with more force than even the Italian police might consider necessary.

    As Elinor Ostrom pointed out: "An extraordinary number of field studies have found that local groups of resource users, sometimes by themselves and sometimes with the assistance of external institutional arrangements, have created a wide diversity of institutional arrangements for coping with common-pool resources where they have not been prevented from doing so by central authorities."

    This is not to say that resource degradation does not happen, only that the 'T of the C' concept should not be used without explaining that it is a misnomer. A more accurate term might be something like 'Tragedy of Unrestricted Access to Non-policed Resources'; this may seem pedantic but it is a very important issue, because the Tragedy concept is used by right-wingers to justify seizing commons land in the name of conservation, only to then exploit it for their own ends.

    1. You are perfectly correct: Hardin had a good idea, but he explained it with the wrong example: the "commons" he was describing never experienced the "tragedy". This is one of the reasons why I wrote this post. I added a line to the post to include this concept, and thanks for the comment!

    2. True, except that to link solely 'right-wingers' with destructive activities is a rather naive viewpoint: can we not go beyond mere political stone-throwing? It is too late in the day for that:

      The Soviet system, with resources theoretically owned by all, was quite as destructive as any capitalism solely intent on profits for individuals or shareholders. Ditto China. They can concede nothing to the US and Europe in terms of short-sighted stupidity in pursuit of a gain which is blind to the effect on the whole system.

      Societies that manage their commons reasonably well might also be rather 'conservative' and probably 'feudal', and therefore on the so-called 'right' of the political spectrum, for those who think in kinder-garten terms. In which case, long live feudal conservatism!

      Do not look at what people call themselves or the idiologists call them, look at what they do.....

    3. "Do not look at what people call themselves or the idiologists call them, look at what they do....."

      It is sometimes said that what was liberal yesterday is conservative today. It can also be vice versa. My late father often said that effective revolutionaries can be hard to label.

  6. Just abandon the car in the garage. Then the garage owner can pay the towing fee on it. In fact, buy a few old wrecks and drive them to the garage and park them there and abandon them. :) Also have some friends go and puncture the tires so they are harder to tow out. :D You could leave a Dead Skunk inside also for the tow truck operator to deal with.

    Yea, a Commons problem, but I don't think the Tourist Industy or Parking Garages are going to be a great source of income for long for Firenza.


    1. Good idea. I think I should really do it, one of these days.

  7. Not surprisingly, most of the pictures taken and broadcasted nowadays are selfies (thanks to Myfacebook).O tempora o mores!



Ugo Bardi is a member of the Club of Rome, faculty member of the University of Florence, and the author of "Extracted" (Chelsea Green 2014), "The Seneca Effect" (Springer 2017), and Before the Collapse (Springer 2019)