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Although freedom of expression is today under assault by extremists on both the political right and left, it endures as a fundamental liberal value. True liberals understand that no society can remain free if the government has the authority to suppress, mandate, or otherwise control freedom of peaceful expression. This reality holds for indirect government interferences with expression no less than for direct government interferences. It holds also when people express themselves in groups no less than when an individual expresses himself alone.
The justifications for freedom of expression are well-known. The most fundamental of these is rooted in the adult recognition of human fallibility. We can never be certain that the facts and narratives that we today believe to be true are really true. This uncertainty exists even for those facts and narratives that are embraced most warmly and accepted widely. Ditto for facts and narratives favored and peddled by the ruling elite. Freedom of expression ensures that anyone possessing ideas that he thinks worth sharing is able to share these ideas with whomever is willing to listen. Given human fallibility, truth is more likely to be discovered and enhanced, and understanding is more likely to be improved, by the on-going contestation of ideas that is encouraged by freedom of expression. With such freedom, worse ideas over time are likely to be displaced by better ideas.
A second, related justification is that knowledge is often created by the mixing of ideas. Freedom of expression not only allows for better pieces of knowledge or information to displace worse pieces, such as when the Copernican description of the solar system displaced the Ptolemaic description. Freedom of expression also allows for ideas to mate with each other so that they generate not only more knowledge, but knowledge that is new and unique. To use Matt Ridley’s evocative imagery, when ideas have sex, the offspring, while related to each ‘parent’ idea, is its own unique creature. With freedom of expression, ideas mate more promiscuously than when expression is regulated by the state. The result is a large and growing number of new and better ideas competing for acceptance.
A third justification for freedom of expression is that government officials, even if they owned superhuman access to truthful information and knowledge, are often incited to use their information and knowledge to further their own interests at the expense of the public. Freedom of expression allows members of the general public to speak out against these abuses of the public trust, thus keeping government officials more honest than they would otherwise be.
Importantly, freedom of expression implies freedom to spread, whether inadvertently or intentionally, information that’s mis, dis, incomplete, or otherwise faulty or confusing. The very logic of the core case for freedom of expression is rooted in the realization that the best test for the veracity of any bit of knowledge or information is its ability to win acceptance in open competition with different bits of freely expressed knowledge or information. Some bits of information and knowledge ‘win,’ at least temporarily, over other bits. But these victors remain forever subject to being deposed in favor of alternative ideas.
A regime of free expression, therefore, cannot be said to ‘fail’ simply because it features false or misleading information. The production of ideas that are later exposed as ‘false’ or misleading is baked into the logic of a policy of freedom of expression. Furthermore, we rely upon private actors, not government officials, to police against faulty information and to devise the appropriate responses and ‘solutions.’
Why Not for Other ‘Imperfections’?
Opponents of freedom of expression typically justify their favored restrictions by insisting that, absent these restrictions, the public will be unjustly harmed by the unregulated emission of dangerous ideas. For example, “If Smith is allowed to contradict public-health authorities on the dangers of COVID, then people exposed to this disinformation will behave in ways that cause them and others to get sick and die. Government must prevent such harms!”
The alleged justification here for government intervention is that freedom of expression harms innocent third-parties. Smith’s words are toxic pollutants emitted into the brains of innocent individuals. Fortunately, though, most liberals, both of the classical and modern American varieties, continue, for reasons reviewed above, to look askance at government intervention aimed at controlling such ‘thought pollution’ – which presents something of a mystery. If government intervention to control the emission of ideas is widely believed to be not only unnecessary but also a positive danger, why is government intervention to control the emission of physical things – say, carbon gasses – believed to be necessary and good?
The reason for this difference cannot be that carbon emissions are harmful while ideas are not. There is likely little social upside to pornography and arguably real downside. Even worse, antisemitism and racial bigotry are nasty and harmful ideas that sometimes lead to the death of innocent people. Yet liberals are deeply reluctant to empower the state to shut down pornographers and to restrict bigoted speech. Such reluctance is right. Nor can the reason for this difference be that there is no upside to the activities that emit physical pollutants. Production of the likes of tires, furniture, steel, speedy transportation, and air conditioning and home heating is surely good for humanity. But such production requires energy and it produces harmful by-products.
A plausible case can be made, I think, for treating physical pollution in the same way that we Americans treat bad ideas – namely, relying for the policing and control of physical pollution on private actors rather than on the state. All sensible people understand that government officials cannot be trusted with the power to filter out ‘unacceptable’ sources of information from ‘acceptable’ sources. Why, then, do we trust these same officials with the power to filter out ‘unacceptable’ sources of industrial emissions from ‘acceptable’ sources?
In my next column I’ll lay out the argument – admittedly a difficult one – that the same strong (albeit not insurmountable) presumption that we apply against government attempts to police emissions from our mouths and keyboards should apply also against government attempts to police emissions from our factories and automobile tailpipes. At the very least, analogizing physical emissions to the emission of ideas provides useful insights into some potential pitfalls of turning to the government to regulate industrial emissions.