Do you consider yourself to be intelligent? In your opinion, are you reasonably well-educated in scientific matters? Well let’s find out, shall we? Answer true or false to the following statements:

• All radioactivity is man-made
• Lasers work by focusing sound waves
• Electrons are smaller than atoms

I’m prepared to guess that you didn’t find this quiz too difficult, in which case you are well on the way to obtaining a high score on the Ordinary Science Intelligence (OSI) scale. Normally that would be a good thing, but the chances are that you are reading this article because there is at least one aspect of climate policy that troubles you. In which case (I am led to believe) your high OSI score has been your worst enemy. Apparently, you will have used your ‘scientific intelligence’ to justify to yourself what are actually highly anti-scientific viewpoints. You know the sort of thing I am talking about: things like questioning the true epistemic value of scientific consensus, or worrying that ostensibly objective scientific advice can be laced with political motivations. No one is saying that these are not the concerns of an intelligent individual, but there are some who think it is an intelligence that is being put to bad use, i.e. the denial of incontrovertible climate science facts. The accusation made is that you simply choose to ignore these climate truths because it suits your personal identity to do so. Your resistance is supposedly emotional, and your intellectual arguments are no more than convenient rationalisations, designed to provide a pseudo-logical justification for having your beliefs and feelings in the first place.

These ideas are supported by the work of Dan M. Kahan, professor of law and psychology and inventor of the OSI scale. He had invented the scale because he wanted a reliable metric that he could use to determine whether a lay person’s understanding of scientifically controversial issues is governed by a so-called information deficit, or whether something else was going on. He discovered that, in the general case, a person’s views on matters such as climate change were not strongly determined by their OSI score. However, he found that OSI was a factor when ideological leanings were taken into account. For those with left-wing liberal viewpoints, the OSI score was a strong factor determining how much the individual was likely to uncritically accept the scientific consensus; the higher the OSI, the greater the level of acceptance. However, the reverse was true of the conservative thinker; higher OSI scores corelated with higher levels of scepticism. Each group was using its scientific understanding to justify what is in fact an ideologically motivated position and, as a result, higher levels of intelligence were just leading to increased polarisation.

I’m not actually very surprised by any of this. I’ve long said that our rationality cannot be taken at face value and that we are strongly motivated to protect our values and identity. Moral outlook has a bearing on how one’s scientific understanding plays out, and emotion plays a greater role in our decision-making than we care to acknowledge. And if that were the end of Kahan’s findings I would have nothing to complain about. However, unfortunately, we are talking about a psychologist here, and so you should not be surprised to discover that there is a bias blind spot lurking in the detail. To see this, one has to examine the figure used by Kahan to illustrate his findings:

To the left you can see how, in the general case, higher OSI modestly increases agreement with the statement made. However, to the right one can see that higher OSI strongly increases agreement from the left-wing liberal group but has the opposite effect for the conservative thinker. Dan Kahan offers a number of reasons for this polarisation, suggesting in particular that where one lies on the individualistic-communistic axis of thinking, or on the hierarchical-egalitarian axis, determines how your OSI influences one’s judgment. This is all very interesting, but I don’t want to talk about that. What I want to point out is an important detail in the above figure: the y-axis is labelled ‘Probability of correct response’.

Firstly, it is relevant to say that Kahan is very likely to be a left-wing liberal (a poll shows that the left-right ratio within the profession is about 15:1). I also assume his OSI is very high. This would put him right up there at the top of the blue curve, in which case it should be no surprise that he would label the figure in the way he did. When it came to it, he couldn’t prevent his views from corrupting the analysis of the data. What should have been presented as an illustration of polarisation, with no judgment being made either way, has been turned into a graph that purports to show that right-wing intellectuals are unique in using their intellect to defend a scientifically indefensible position. In contrast, the left-wing thinker’s agreement with the statement is equated to a superior understanding of the issue. For the left wing, education has proven a good thing, but for the conservatives it turned out to be just an instrument for self-deception. Or so says the Kahan graph.

But when you look at the question asked, we are not talking about an objective issue here — we are not talking about the size of electrons. The question relates to a subjective judgment regarding whether “solid evidence” exists. When people answer true or false, they are not offering a right or wrong answer; they are declaring what they are prepared to characterise as “solid”. For example, some may say that the term “solid” is very appropriate given that the IPCC has declared the likelihood to be “high” (another term that is, however, open to interpretation). But not everyone has confidence in the reporting methodologies of the IPCC, particularly given the possibility of prosocial censorship playing a role. At the end of the day, opinions are being expressed and the graph shows a polarisation of those opinions. The graph cannot, therefore, be presented as proof that those of a particular ideological persuasion are uniquely susceptible to a cognitive failing leading to poor understanding. And yet that is precisely the interpretation Kahan’s diagram invites.

Such invitations are rarely declined; the opportunity to characterise climate scepticism as a cognitive ailment is just far too tempting for some. And so, we have academic papers such as, “Climate Change Denial as Identity Defence: Understanding Resistance Beyond Ignorance”, in which it is stated:

Climate denial is often misunderstood as ignorance, but evidence from neuroscience reveals it as identity protection.

You are welcome to read the rest of the paper if you wish, but you will search in vain for any recognition that climate advocates are just as guilty of using their intelligence to protect their identity, and so their own position also has to be seriously challenged. Then, of course, The Guardian insists on getting in on the act by bemoaning how apparently intelligent people can conveniently ignore what they surely must know to be true. Incredulously, it asks of ‘climate denier meetings’:

Could an audience of experienced, intelligent people really be this blithely indifferent to the devastating impacts that unmitigated climate change will wreak on the world their progeny must inhabit?

Assuming that such ‘denier’ audiences are familiar with the concept of insuring against future calamity, it then asks:

Why then, when it comes to assessing the greatest threat the world has ever faced and when presented with the most overwhelming scientific consensus on any issue in the modern era, does this caution desert them?

And there was me thinking that the most overwhelming scientific consensus on any issue in the modern era was that electrons are smaller than atoms. Anyway, the posited sceptical lunacy on display is then explained in terms of the selective application of scientific knowledge in the pursuit of self-interest:

Short-termism and self-interest is [sic] part of the answer. A 2012 study in Nature Climate Change presented evidence of “how remarkably well-equipped ordinary individuals are to discern which stances towards scientific information secure their personal interests”.

Once again, you are welcome to read the rest of the article, but if you were hoping to find a balanced assessment of the phenomenon of motivated reasoning, you must prepare yourself for disappointment. As far as The Guardian is concerned, such maladaptive thinking is the sole preserve of the elderly, white male! That said, The Guardian is more than a little anxious to protect its sacred cows:

It is, however, deeply unfair to tar all elderly white men as reckless and egotistical; notable exceptions include the celebrated naturalist David Attenborough and the former Nasa chief Jim Hansen.

Speaking as your average reckless, egotistical, elderly, white male, I have to say that there are plenty within my demographic who are zealously supporting the idea of net zero by 2050, without so much as the slightest understanding of just how much intelligent self-deception that requires.

Of course, the weaponizing of behavioural science insights is nothing new; characters such as John Cook are making a highly successful career out of it. Actually, I struggle to think of a behavioural scientist who isn’t. The problem isn’t that research such as that undertaken by Dan Kahan is flawed; it is that it is applied in such a highly tendentious manner. I am quite prepared to concede that I apply my intelligence in defence of my values and beliefs. I just wish that those in the psychology profession were prepared to admit the same of themselves. In fact, if there has ever been a professional group that uses its intelligence to protect its own values, it must surely be the behavioural scientists. There is more than a hint of hypocrisy here, and I have to say that there is nothing more ironic than a bias blind spot that involves a professional group accusing others of being uniquely susceptible to bias blind spot.