Environment and Society. Paul Robbins
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individuals making decisions in pursuit of their own interests tend to create collective outcomes that are non-optimal for everyone
A popular metaphor for situations such as these is the story of the Prisoner’s Dilemma. In this tale, so often replayed on contemporary television crime dramas, you are asked to imagine two people charged with a crime, perhaps something like burglary, in which the best evidence that the police have (though not the only evidence) would be the testimony of one of the burglars against the other. Both suspects are taken into custody by the police and interrogated individually. Each is separately told that if they testify against the other person, they will go free or have a greatly reduced sentence. The logical decision in a perfect world is for both of the suspects to keep their mouths shut. With no one talking, they might each serve a short jail term, if any term at all. The problem stems from the fact that each knows that the other might well “rat” him out. If one chooses not to talk while the other “rats,” the reticent one will do hard time while the other one goes free. Since no one wants to be a “sucker” and suffer at the hands of the other, the predictable outcome is that both testify against the other, leading to the worst possible mutual outcome, one in which both do hard time. Trying to anticipate and avoid the punitive “defection” of the other person, the two partners act in service of the police. Such a situation not only invites each person to “rat” out the other, it actually makes it rational to do so, even though the outcome is inevitably bad for everyone, something no rational person would choose if they could control the behaviors of both parties.
Game Theory A form of applied mathematics used to model and predict people’s behavior in strategic situations where people’s choices are predicated on predicting the behavior of others
These sorts of fascinating dilemmas are the province of game theory, adopted by thinkers who employ a form of mathematical analysis of decision-making, examining those sorts of situations that might be expressed in game terms. For game theorists, certain games provide models for how people think and behave. Of most interest are games where the crux of the problem is anticipating what the other player might choose to do, where bluffing and second-guessing are paramount. Such is the case of our two prisoners, who individually reach what is ultimately a bad mutual decision because they are trying to anticipate what the other prisoner might decide to do. Along these lines, and as established by the refugee scientist John von Neumann after World War II, game theory understands a “game” to be “a conflict situation where one must make a choice knowing that others are making choices too, and the outcome of the conflict will be determined in a prescribed way by all the choices made” (Poundstone 1992, p. 6).
In game theory, as in the Prisoner’s Dilemma, the best outcomes are typically achieved by cooperating, while individual incentives tend to lead to a reason not to cooperate. The problem of our two suspects might be expressed in abstract terms by game theorists as in Figure 4.1. These games can be made ever more complicated by introducing quantitative cash rewards and punishments and making the decisions more complex, involving, for example, investment in a public good versus a private bank, and so on. Complex mathematics can be used to predict behaviors, including retaliations, mutual learning, and system collapse.
Figure 4.1 The Prisoner’s Dilemma in game-theoretical terms. The best outcome, in the upper left, is also the least likely, since each player prefers to avoid the worst individual outcomes, in the upper right and lower left corners, leading to the worst collective outcome, in the lower right.
The Tragedy of the Commons
The first applications of game theory mathematics were directed to the Cold War logic of mutual nuclear annihilation. Funded by the RAND Corporation and the US Pentagon in the 1950s, game theorists asked the unthinkable: Is it rational to strike first with nuclear weapons, not knowing whether and when the enemy might do so? Is it rational to drop the bomb?!
But what might any of this have to do with environment and society? Applying this kind of thinking to our interactions with the natural world leads to some potentially grim and tragic conclusions. For while there is a possibility of cooperation around environmental conservation, there is a potentially overriding incentive to “defect,” in the language of game theory, leading to a general inability to manage or control our consumption and use of the environment, and so to environmental destruction.
Thinking along these lines, Garrett Hardin presented one of the most compelling, persistent, and in some ways problematic arguments linking environment to society through the commons. In his article “The Tragedy of the Commons,” published in Science in 1968 (where von Neumann is prominently cited), he directed this logic to the problem of overpopulation. He argued that while the advantages for any individual or family of reproducing freely are immediate, their costs are diffused across the planet, increasing incrementally the burden of humanity upon the Earth. This is a Prisoner’s Dilemma, insofar as some people may choose to forgo more children in the interests of the planet, but others will inevitably “defect” or cop a “free ride.” The worst outcome is much more likely (now sometimes called the “Nash Equilibrium” for its mathematical discoverer John Forbes Nash, made famous in the film A Beautiful Mind), at least without some form of coercive restraint on people’s behavior. Overpopulation, as this logic goes, is inevitable without some form of enforcement mechanism (Chapter 2).
The article was made more compelling by its use of an agricultural metaphor for the problem. Rather than think directly about people’s reproduction, Hardin asked us to “picture a pasture open to all …” in which numerous herdsmen managed their individual herds. Following precisely the logic of the Prisoner’s Dilemma, it is in the interest of each herder to increase the size of their own herd, Hardin argued, since each new animal costs him nothing but gains him much. But since all herdsmen enjoy the same incentive, the inevitable result is a destroyed pasture. Because it belongs to everyone, the resource belongs to no one, and will inevitably be grazed into destruction. In language typical of the article he explains:
Ruin is the destination toward which all men rush, each pursuing his own best interest in a society that believes in the freedom of the commons. Freedom in a commons brings ruin to all. (Hardin 1968, p. 1243)
Conscience and goodwill, Hardin further asserted, were useless in the face of compelling, internal, adaptive, evolutionary logics. Real solutions, however distasteful, must inevitably take some other form. People of the Earth must choose either coercion (“mutual coercion mutually agreed upon,” p. 1247), to tyrannize ourselves into control, or turn to strict forms of private property and inheritance so that all impacts of poor decision-making will be visited only upon the owner of that property. The former approach was rejected by Hardin, as he concluded that the problem with tyranny is that there is always a possibility that a system of governance will come under the undue sway of one of the users of the commons and cannot itself be controlled: “Quis custodiet ipsos custodes – ‘Who shall watch the watchers themselves?’” (pp. 1245–1246). The latter approach – privatization – was preferred and defended by Hardin since, no matter how unjust it might be (not all rich people are smart people, he pointed out: “an idiot can inherent millions,” p. 1247), such a solution was the best one available. In either case, whether state or private control, some form of enclosure was deemed as essential, where an “open access” resource is bounded and given over to control either by individual owners or by a strong state management body.
The power and influence of this argument were enormous, and remain so to this day. It continues to be perhaps the most cited academic article in the social sciences, it provided foundational arguments for fields as widespread as evolutionary biology and economics, and it is typically invoked in debates over environmental scarcity. Because Hardin convincingly used an environmental crisis as his metaphoric example, his essay on population quickly became the key defining metaphor for many people (managers and scholars) in guiding their thinking