I’ve been meaning to write this post for a while, and Paul Krugman has given me a nice jumping off point with this column on how to respond to economists (including highly credentialled ones) who push zombie ideas such as the threat of imminent hyperinflation. As Krugman notes, providing evidence-based criticism, whether politely or rudely, has no impact on people who have strong reasons for wanting to believe something. This is even more true on topics like climate change than it is on economics.
Dan Kahan, among others, has made much of this fact, drawing the conclusion, in relation to the debate on vaccination that
The “anti-science trope,” in sum, is not just contrary to fact. is contrary to the tremendous stake that the public has in keeping its vaccine science communication environment free of reason-effacing forms of pollution.
Despite the phrase “contrary to fact”, Kahan doesn’t, as far as I can see, refute the anti-science trope that
concern about vaccine risks to disbelief in evolution and climate skepticism, all of which are cited as instances of a creeping hostility to science in the U.S. general public or at least some component of it.
. Indeed, it’s hard to see how it could be refuted, given that the attitudes cited are both widely held and obviously opposed to the conclusions of science. All he shows is that antivaxerism is much more of a minority position than climate denialism or creationism
Kahan does, however, show pretty convincingly that the use of the anti-science trope in relation to a particular issue tends to deepen the divide between the pro-science and anti-science sides, reinforcing each in their beliefs. Thus, he concludes, this trope should be avoided. The same kind of line has been put many times in relation to climate change.
The implicit, and false assumption in the anti-anti-anti-science position is that there is some better way of convincing the anti-science group to change their minds, for example by framing climate change in terms more congenial to political rightwingers. This is pretty clearly wrong. Long experience has shown that nothing is going to shift the right on an issue that has become a tribal shibboleth.
As Krugman points out, what matters is not the impact on the anti-science group themselves, but on the attitudes to that group among others. The recent measles epidemic didn’t have much of an impact on anti-vaxers, as far as I can see, but it certainly changed attitudes towards them, greatly reducing sympathy for their desire to pursue their deluded beliefs regardless of the risk to the rest of the community.
The other aspect, which evidently pains Kahan, is that this issue has a clear partisan dimension. Not only are specific anti-science attitudes far more common on the political right, but responses to the anti-science trope also break on partisan lines. I can’t find a link now, but the experimental evidence shows that the reinforcing effect of contrary evidence is stronger among Republicans than Democrats. The differences are much starker among the politically active: the discrediting of antivaxerism on the political left is just one example.[^1]
Following Krugman, the effect of the anti-anti-science trope is not to persuade Republicans but to undermine the centrist view, dominant until very recently, which saw the ideal outcome of politics as a bipartisan deal in which Republicans prevailed on most point. The underlying assumption that the Republicans were the sensible party has been eroded very gradually over time.
It’s an obviously debatable question as to whether this development will ultimately harm the right and benefit the left. Recent Republican electoral successes tend to support the observation of the con-man in Huckleberry Finn
“Hain’t we got all the fools in town on our side? And hain’t that a big enough majority in any town?”
On the other hand, IIRC, he ended being tarred, feathered and run out of town on a rail.
[^1]: The only remaining issue on which parts of the left still take a full-blown anti-science line is the claim that consuming GM foods has adverse health effects. There are plenty of reasons for concern about GM crops, and other aspects of the privatisation of genomic resources, and continuing to push discredited research on safety risks only weakens the position of anyone seeking to raise those concerns. But even here, it’s clear that the pressure to present a position in line with mainstream science is increasing.