In a recent post, here and on Crooked Timber, I remarked on the fact that hardly any self-described climate sceptics had revised their views in response to the recent years of record-breaking global temperatures. Defending his fellow “sceptics”, Crooked Timber commenter Cassander wrote
When’s the last time you changed your mind as a result of the evidence? It’s not something people do very often.
I’m tempted by the one-word response “Derp“. But the dangers of holding to a position regardless of the evidence are particularly severe for academics approaching emeritus age. So, I gave the question a bit of thought.
Here are three issues on which I’ve changed my mind over different periods
The link on central planning gives a full explanation of my change of position, so I’ll leave it at that.
As regards, war I was, before the Iraq war, a reasonably strong supporter of “humanitarian intervention” and, in particular, of the war in Afghanistan. In the leadup to the Iraq war, I was willing to give Bush and particularly Blair the benefit of the doubt for a long time. Partly as a result of that war, and subsequent episodes, and partly through rethinking the issues, I’m now deeply sceptical of any argument for war, including humanitarian intervention. More generally that scepticism applies to any case for political violence, including revolutionary violence.
On climate change, I’ve made several, interrelated shifts from the position I set out in the linked post from 2004. First, and in response to the massive decline in the cost of renewable energy (solar PV and wind), I’ve drawn the conclusion that renewables provide a feasible basis for decarbonizing the economy, while nuclear power does not. The plummeting cost of solar also implies a much lower cost for replacing coal and gas with renewables and therefore a smaller increase in the implied cost of carbon-free electricity. That in turn means that the goal of decarbonizing the economy can probably be reached in large measure through regulatory policies of various kinds, with only a modest increase in cost. Since there is much more effective political resistance (particularly on the political right) to price-based policies and market mechanisms than to regulations and tax breaks, it makes sense to go this way.
Those aren’t the only issues on which I’ve changed, but they are a sample. I’ll conclude, inevitably, with an apparently apocryphal link to Keynes.
fn1. Even more dangerous is a willingness to defend views dictated by tribal affiliation, regardless of the facts, and of the need to abandon previous positions the moment they become inconvenient. That might seem like a source of political strength in the short run, as it was for the US Republican Party for many years, but the endpoint is a movement run by people like Palin and Trump.
fn2. One of the more striking instances of derp in the energy debate is the continuing prevalence of people, mostly on the right, who concluded in the early 2000s that nuclear power was the best option, and who continue, not merely to maintain this view in the face of the evidence but to argue that the failure of environmentalists to advocate nuclear power represents a denial of evidence comparable to climate science denial. Unfortunately, this argument is assisted by handful of people on the pro-climate side, notably including George Monbiot, who’ve overcorrected their previous outright rejection of nuclear power.
fn3. As with Einstein, Keynes appears to be a natural recipient of credit for clever things he might well have said, but didn’t.