Is there any way to escape the prisoner’s dilemma facing the provision of a public good?

The problem was first noticed by the 17th-century philosopher Thomas Hobbes, seeking the justification of political authority. Hobbes’s question of how to escape anarchy poses a prisoner’s dilemma. The rule of law, he recognized, is non-rivalrously and non-excludably consumed, even for the weakest, the poorest. It’s obvious of course that some laws are better for some people than for others. But Hobbes argued that any laws, even the laws of a tyrannical dictator, no matter how harmful they may be, confer some minimal non-excludable benefit on everyone that we can consume non-rivalrously.

The enforced rule of law, any law, at least gets us out of the state of nature, where “the life of man is solitary, mean, nasty, brutish and short.” Hobbes argued that the only way to provide this public good is for each of us to surrender all power to the state so that it can compel obedience to the law. Hobbes’s recipe for escaping the prisoner’s dilemma of anarchy never attracted much support. The history of political philosophy from Locke to Rawls is a sequence of proposed alternatives to Hobbes’s strategy. Each sought a basis on which people can credibly bind themselves voluntarily to provide the public good of “law and order.”

Once the philosopher identifies the problem, the political scientist can approach it empirically: Try to identify the circumstances in real life where people have spontaneously solved the problem of providing themselves a public good, in their self-interest and without coercion.

For answering this question, the political scientist Elinor Ostrom won the Nobel Prize that was supposed to go only to economists. She spent a career identifying the conditions, all over the world, including the developing world, under which groups manage to solve the prisoner’s dilemma by voluntarily creating institutions — rules, norms, practices — that every member benefits from, non-rivalrously and non-excludably. In doing so, Ostrom provided a recipe for how to avoid the prisoner’s dilemma that a public good presents.

The ingredients needed are clear: The participants have to agree on who’s in the group; there’s a single set of rules all participants can actually obey; compliance is monitored effectively, with graduated punishments for violation; enforcement and adjudication is affordable; and outside authorities have to allow the participants to obey the rules. Finally, in the long term, the group providing the public good to its members has to be nested in, authorized by higher-level groups. These in turn persist when they can provide themselves a different set of nonexcludable, nonrivalrously consumed, mutually beneficial rules, norms, laws and institutions.

It’s not rocket science to see how hard it would be for the 200 or so nations of the world to satisfy these conditions. The Paris agreement is a far cry from Ostrom’s recipe. The main obstacle to carrying it out will be the unwillingness to surrender national sovereignty.

But now at least we have a good idea of what we are up against, and even some tools to get closer to a solution. For example, citizens and nested groups of citizens can employ Ostrom’s recipe to build increasingly more global responses to climate change, thereby providing at least some of this public good to many people.