In my previous column, I argued that liberals’ confidence in freedom of expression is perhaps inconsistent with ready acceptance of the case for using the government to ‘control’ air pollution and other negative externalities. Ideas are emitted and spread from human minds and mouths just as greenhouse gasses are emitted and spread from automobiles and factories. And like greenhouse gasses, ideas can be harmful. Yet government officials whom liberals distrust to police the emission of ideas are trusted by those same liberals to police the emission of physical elements, such as greenhouse gasses.
There might be a sound explanation for this apparent inconsistency and, hence, good reasons to accept government intervention to control physical pollution. But if so, these reasons aren’t immediately obvious.
Our wise awareness that we can never be sure just which ideas are right and which are wrong should apply to physical emissions. Take what is today the big bad monstrous emission: CO2. Very many people believe as a matter of indisputable fact that in an ideal world the amount of CO2 emissions would be zero. Perhaps this belief is true, but perhaps not. Consider this recent observation from the science writer Matt Ridley: “Given that roughly ten times as many people die of cold as die of heat globally, and that this is true even of countries like India and Italy, warming has meant fewer people dying.” Because CO2 emissions do likely raise the earth’s average temperature, perhaps these emissions produce, on net, positive benefits.
I write “perhaps” because I don’t know. But because human life is valuable, the above claim isn’t ludicrous. Indeed, I believe it to be plausible. The larger point, however, is that no one knows.
While science can tell us much about relatively simple relationships – for example, the extent to which CO2 emissions do in fact warm the earth, the various available technological means for reducing the amount of CO2 in the atmosphere, and whether more people really do die from cold rather than from heat – we can never be certain that such pieces of scientific information are correct. A more foundational problem, however, is that science becomes ever more error-prone the greater is the number of detailed variables across space and time that it is asked to account for and predict. Science cannot tell us today how human ingenuity will tomorrow respond to climate change – how an agronomist might innovatively change farming practices to turn rising temperatures from a danger into a boon, how a civil engineer might redesign dykes to protect coastal communities from rising sea levels, or how individuals will change their locational preferences to reduce their exposure to climate change.
All we know here is that humans are innovative and have a great capacity to creatively meet challenges without being prodded by politicians or mandarins. But no one can predict in detail how this creativity will manifest itself. It follows that any central plan for dealing with climate change will be done in ignorance of future knowledge and possibilities. And if, as is likely, imposing a central plan to ‘address’ climate change will block several alternative avenues for dealing with climate change, many inadequacies in today’s centrally imposed plan will forever remain undiscovered and uncorrected. What will perhaps appear in the future to be a splendid response to climate change might well have been exposed as seriously defective had decentralized approaches not been suffocated by a scheme centrally designed and imposed.
In short, if we don’t trust politicians today to have sufficient knowledge to protect us from bad ideas, why do we trust them to have sufficient knowledge to protect us from bad physical pollutants? And if we trust that, over time, truth is more likely to be vigorously pursued and discovered and spread when individuals are free to speak and write absent state interference, why do we not also trust that, over time, a cleaner environment is more likely to be vigorously pursued and discovered and spread when individuals are free to deal with climate change absent state interference?
A similar question arises regarding government-officials’ motivations. The liberal rightly rejects any suggestion that even fully informed politicians and bureaucrats can be trusted with the power to coercively proscribe and otherwise regulate speech and other forms of peaceful expression. What, then, is the source of the trust that so many liberals (and non-liberals) put in politicians and bureaucrats to coercively proscribe and otherwise regulate peaceful activities that emit physical pollutants? Do the venal government officials who cannot be trusted to regulate speech in the public interest lose their venality when they turn their attention to the control of physical pollutants? Might the risk of abuse by government officials of the power to regulate physical emissions be worse than the risk of relying on individuals, acting decentrally, to deal with such pollution? The above ruminations, standing alone, clearly don’t amount to a credible case against emissions taxes and other government interventions meant to control pollution. But by contrasting the accepted – and, I believe, successful – laissez-faire approach to dealing with peaceful expression with the highly interventionist approach to dealing with industrial and commercial activities that emit physical substances into the atmosphere, relevant questions are raised that prod us to think more carefully about widely accepted justifications for government interventions.