In 1968 Garrett Hardin wrote an essay (pdf), The tragedy of the commons, in which he argued that common ownership of assets such as land or fishing waters was incompatible with people being the selfish rational maximizers of economic theory. This is because if every herdsman can graze his cattle for free on commonly-owned pasture land each will want to put as many cattle on it as he can - until the land becomes over-grazed and barren. In this way wrote Hardin, "freedom in a commons brings ruin to all."
The same problem, warned Hardin, applies to pollution:
The rational man finds that his share of the cost of the wastes he discharges into the commons is less than the cost of purifying his wastes before releasing them. Since this is true for everyone, we are locked into a system of "fouling our own nest," so long as we behave only as independent, rational, free-enterprisers.
In saying this, Hardin was expressing in economic terms what many philosophers have pointed out - that there's a potential tension between the assertion of individual freedom and a thriving public realm. In 1935 John Macmurray wrote:
If the forces making for individual independence and initiative - for individualism in fact - become overmastering, they disrupt social unity and produce a catastrophe. (Reason and Emotion, p69)
Or as Charles Taylor put it:
A society of self-fulfillers...cannot sustain the strong identification with the political community which public freedom needs. (Sources of the Self, p508)
Many on the right used to be alert to this. They criticized alternative lifestyles such as "free love" and homosexuality on the grounds that they eroded traditional communities.
Today, though, we face the conflict in another context - that of the public sphere, the area in which questions get (or don't get!) debated.
This, like common land, a public good. A culture which values free scientific inquiry and the pursuit of truth, for example - and which embeds these in institutions such as universities - is likely to produce technologies and medicines which benefit us all. Likewise, most people believe that it's in all our interests that political debate facilitate good policies and good governance. One reason why John Stuart Mill and his followers valued freedom of speech and thought was that they believed these fostered better ideas from which we all might benefit.
Which brings us to the problem. Our public sphere as it now exists does not do this. Under Musk's ownership Twitter has degraded from a common forum into what Christina Pagel has called a means of weaponizing anger and disinformation. And Hardeep Matharu writes:
Social media platforms rife with conspiracy, disinformation, and hate are what people are seeing daily – and where they develop their sense of the world they live in. Social media is now the media. In this ecosystem, what matters is what resonates, regardless of how outrageous.
Which vindicates Hardin. Musk's pursuit of self-advantage has ruined a (once-) important part of the commons. But the problem is not just Twitter. Anyone who remembers the Sun in the 80s knows that the legacy media has always pumped out lies and hate. What's more recent, though, is that in an attempt to staunch losses caused by falling circulation, newspapers have slashed the number of specialist reporters. That, writes Sam Freedman in Failed State, "has degraded the quality of coverage and made it easier for politicians to pursue bad policy and avoid scrutiny." And our political ecosystem too often selects for snake-oil sellers, charlatans, liars and the incompetent.
We have therefore a tragedy of the commons.
So what are the alternatives?
To see some, remember that there's nothing inevitable or universal about the tragedy of the commons. Far from it. As Elinor Ostrom pointed out (pdf), common ownership of resources can very often be successful, under particular conditions.
What's needed here is that users of the commons do not "behave only as independent, rational, free-enterprisers". Instead, they must limit the extent to which they exploit the commons - a practice known as stinting (pdf). In our context, stinting would consist of something like what Habermas called discourse ethics: norms of honesty, openness, diversity and rationality. That's why there was traditionally a strong convention in parliament against lying to the House.
In principle, such rules could be voluntary, with users of the public sphere having the necessary virtues. Many, however, do not. In discharging hate and lies into the public sphere, they are fouling the nest for the rest of us. "Political entrepreneur" should be an oxymoron.
Virtues, then, must be complemented by sanctions. Historically, those who despoiled the commons were sometimes subjected (pdf) to "rough music", a form of public shaming. The latter-day equivalent of this is the mocking or correcting quote-tweeting of hateful or wrong claims. The problem with this, however, that it (sometimes) backfires. As Tim Harford has written:
Repeating a false claim, even in the context of debunking that claim, can make it stick. The myth-busting seems to work but then our memories fade and we remember only the myth.
This leaves another possibility: common ownership. Hardin's tragedy of the commons could be retitled the tragedy of private ownership, because if cattle or fishing boats were commonly owned the community could agree to restrain their exploitation of the commons. In our context, this argues for common democratic ownership of the media or at least for a media ecosystem more diverse than one controlled by a few billionaires.
But, but, but. We do have an organization which was founded in part precisely to resist the tragedy of the commons and to foster a flourishing public realm: the BBC. Its first boss, Lord Reith, saw its role as shoring up the public sphere:
As we conceive it, our responsibility is to carry into the greatest possible number of homes everything that is best in every department of human knowledge, endeavour and achievement.
In an anticipation of Hardin, he thought that private ownership could not do this. "No company constituted on trade lines for the profit of those composing it can be regarded as adequate" he said.
You only have to watch Laura Kuenssberg or (worse still) listen to Jeremy Vine to appreciate that the BBC is no longer fulfilling Reith's objectives*, preferring instead to give a platform to billionaires' gimps or even to outright racists. Which tells us that common ownership on its own is not sufficient. But what is? How can we democratize the media without it falling under the influence of cranks and fanatics pushing their own agendas?
The problem is that the degradation of the public sphere means that not only is there no adequate forum for answering this question, there isn't even interest in asking it; a big fault with our political system is that some important issues are off the agenda whilst trivial ones are on it. And this is one of the tragedies of the commons.
* Of course, there's far more to the BBC than current affairs. Ironically, the BBC meets Reithian principles better when making commercial programmes than when fulfilling its public service remit.