Tragedy of the Commons

I’ve just finished my first weekend training Green Steps – it was tough, but rewarding, and I feel I’ve learned a lot about delivering long presentations and engaging with a group. I drew a couple of major things out of the weekend – neither concept is new to me, but I’d never considered them so thoroughly! One is that, when delivering any presentation, the speaker needs to have the narrative and take-home messages foremost in their mind, to make sure the audience ‘gets it’. The second is a firmer understanding of the inter-relatedness of our production systems, which ultimately means that we, as consumers, are effectively responsible for the lion’s share of exploitation of the environment.

I plan to flesh out my thoughts on these issues in future blog posts, but for now, I’ll try to summarise what was probably the concept which started me on the track of properly considering the impact of people on the environment. It’s called the Tragedy of the Commons. Here’s how it goes:

When a number of people have access to a free (or very cheap) common resource, the rational thing for each individual to do is use as much of the resource as they can. Garrett Hardin, the author of the original 1968 article, used the metaphor of farmers running cows on a common pasture. Each farmer can add more cows to the pasture. The pasture can support a good number of cows, but over a certain point, it will start to be damaged, which will be a problem for all the farmers.

From the perspective of an individual farmer, they can either add a cow (thereby gaining more revenue) and maybe the pasture will suffer some degradation, or not add a cow (and get no revenue). The rational thing to do, for each farmer, is run as many cows as possible. However, if all the farmers act this way, the pasture will be trampled, the cows will die and the farmers will lose their resources.

I encountered this idea in a course on the Global Environment in the first year of my Environmental Science degree, and I was struck by just how widely applicable it is; it seems that in any situation where there is a desirable and accessible common resource, exploitation is difficult to avoid without regulation. Potential solutions include ‘enlightened self-interest’ (in other words, if the farmers become aware that exploitation will eventually hurt them and everyone else, they may, as a group, stop adding cows to the pasture) or intervention by an authority to regulate the resource use. Certainly, we see the effects of the Tragedy of the Commons when we look at natural systems planetwide; the challenge of the coming century will be to help as many people as possible to understand the problems we, as a race, are causing, and further, to facilitate cultural and technological change that can enhance our quality of life while decreasing our exploitation of our planet.

Don't make me chase you.

Don't make me chase you.

Categories: environmentalism, Science, Thoughts | Tags: , , , | 9 Comments

Post navigation

9 thoughts on “Tragedy of the Commons

  1. chad

    I see you gave a speech on rights at one of the skeptics meetings. How does private property rights coesist with an environmentalist perspective tha uses ‘tragedy of the commons’ as its validation?

    • davidpj

      At the skeptics we focused mainly on a case of women’s rights from Sudan, so we didn’t really get into property rights, but it’s a difficult question (and could be a good future topic). In the original Commons article the author argued that even regulation (ie enforced ‘environmentalism’) may fail because people will still act in their own self interest.

      What do you think? Can they coexist?

  2. chad

    no, regulation is a direct violation of property rights imo. Something paid for must be the buyers in entirety and ownership includes having the choice to exploit the land for purposes of self interest or alternatively do nothing to it. It should be their decision. On the other hand, can self interest and sustainable practices be one and the same thing? I think so.

    • davidpj

      I agree, Hardin called that ‘enlightened self-interest’ in the Tragedy example, in that if everyone knows the consequences of overexploitation (ie it hurts in the long run) then it is in their long-term self interest to not overexploit.

      I probably agree on land rights but the lines become blurry when you talk about highly mobile natural resources associated with the land, eg water, air. That’s something currently being argued about with regard to water rights in the Murray-Darling Basin: if a creek flows through your property can you use all the water in it? Or dump waste into it? Or dam it and keep it for future use? It seems some kind of regulation is almost inevitable for some such systems because people can exploit directly at the expense of others (eg water in a creek), as opposed to indirectly (carbon air pollution).

      • chad

        ‘enlightened self interest’ is in my opinion a redundant distinction (‘enlightened’ may be a self evaluation of the author >.o). The thing about self interest though is that negative environmental and productive consequences have to be shown to occur within one life span. Outside of that, management is developed to accomidate such floating abstractions as intergenerational equity :S which is clearly not self oriented. In general though its a fact that we have to exploit our environment to live. Its my opinion that we have to be inventive in exploiting our environment and create more diverse and efficient systems (aquaponics :D, permaculture).

        I agree with you on highly mobile resources. It is impossible (?) to apply the same property rights to these. I was actually under the impression that all water was commonwealth owned? For example if a creek runs through your property – no you cannot touch it. Thats what I learnt in Env. Law. Pollution into these resources though is fairly point source in nature so is regulated? (except for vehicle emissions) You would know more than me.

  3. davidpj

    Fair enough about the ‘enlightened’, I took it to mean ‘informed’. I think you’ve nailed the biggest problem of a lot of environmental issues, which is that the negative effects manifest over (sometimes long periods of) time and generally away from the source. In the Commons example it might be 5 farmers sharing the pasture, but in the world, the negative return is shared among thousands, millions or billions of people (or organisms) and may not be directly felt at all.

    However I think that suggesting notions ‘such as’ intergenerational equity are floating abstractions which do not apply to self interest is unfair, because it relies on a very narrow definition of self interest – the ability to sustain life. If you expand the concept of self interest to include quality of life, I think floating abstractions actually become important, because an idea/impulse doesn’t have to be rationally grounded to influence the state of a person’s mind. There are plenty of altruistic people out there who benefit indirectly from acts which are not specifically self-interested. Intergenerational equity is perhaps a poor example because it fails simply because it’s inherently flawed (time IS change thus one time =/= another time), but the abstraction of equity can affect the quality of life of a person (an old person being comforted by the fact that, due to the choices they’ve made in their life, future generations will inherit more benefits/less problems).

    I have a feeling you will argue this point, and I’m a bit tired now, so hopefully you get what I am trying to say enough to argue with it!

    I would also argue that environmental and productive consequences can, to high degree of certainty (but, unfortunately, not specificity), be predicted within one lifespan. The difficulty is linking the resource use/exploitation to a specific environmental outcome: the “Was Hurricane Katrina caused by global warming?” type of question.

    For mobile resources: I should know stuff about water, but it isn’t springing to mind right now. I believe you’re right that water is a crown resource but recently in many areas the water rights allocations have been overhauled, I think that in the previous system you obtained rights to a certain allocation of water gathered from your property, even if it was higher than the water available (!), and that the only way the Commonwealth could get them back was by purchasing them, because the contracts were very long/indefinite.

  4. Chad

    The point I was making is that benefits have to apply to the individual and be objective, measurable and in the best case scenario monetary if environmental agendas are going to be incorporated into human endevours in the absence of regulation.

    • davidpj

      Fair enough, I mostly agree with that statement. There have been some social movements which have succeeded in gaining support and behaviour change (mostly human rights type issues) without objective/measurable benefits to each individual involved.

      I think what you described is the main reason we’re facing environmental problems at all; in most cases there aren’t clear, measurable, financial reasons for individuals or operators not to exploit the environment to a major extent.

      I’ll be interested to see whether sustainable (whatever that means…) practice becomes the norm this century. I hope it does, because it’d be hard for me to stay positive about the future if it’s not!

  5. Pingback: The nuclear apocalypse of a new generation « David Robertson


Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s

Create a free website or blog at

%d bloggers like this: