(featured image: Robert Couse-Baker CC BY)
It is OK not to know stuff for certain, especially when things are uncertain
Once upon a time, there was a cat. It was a hypothetical cat, owned and imagined by Erwin Schrödinger, a 20th century quantum physicist. Dr Schrödinger had placed the cat in a box, together with a bottle containing cyanide, a hammer connected to a Geiger counter (an instrument to measure radioactivity), and some radioactive material. He had then sealed the box and waited for an hour to pass. The Geiger counter in the box could detect the radioactive material, but there was so little of it that the chance of this happening over the course of one hour was exactly 50/50. If it did, it would release the hammer, which would then shatter the flask with the poison, leading to the death of the cat. Now, without opening the box, could we say whether the cat was alive or dead?
No. As Schrödinger’s famous (and somewhat lugubrious) thought experiment illustrates (see this video for enlightenment), until the box is opened, and we know whether or not the poison was released, the cat is in a kind of indeterminate state – both alive and dead, or indeed neither. Such indeterminacy is not unusual in the field of quantum physics, and quantum physicists happily deal with it. However, in our ordinary world, with objects that are much larger than the tiny particles they work with, we also have to deal with situations where we don’t know whether something is true or false, or even with things that are neither true nor false – situations where we are ignorant. And that is something we may find very hard to handle.
A profound aversion to uncertainty
We appear to have a profound aversion to uncertainty, which seems to be further accentuated by the tense COVID-19 crisis. The vast majority of what we hear and read from the media, from political leaders (and, on social media, from numerous self-proclaimed pundits with little or no relevant competence) exhibits unshakeable certainty. It’s as if it’s only the experts who acknowledge they know very little for certain, and whose statements exhibit nuance.
But we need certainty, and there are plenty of people who are ready to oblige. You may have seen the YouTube video (at the time of writing, it has been viewed 24 million times) in which a family doctor gives advice on how to handle the groceries we buy. One of his tips is to wash fresh produce with soap for at least 20 seconds. This is a bad idea. (Apparently the good doctor has now admitted as much – but in the meantime millions of people may have taken him at his ‘expert’ word). And yet, it seemed to make perfect sense: if washing our hands with soap for at least 20 seconds is recommended, the same must obviously be true for what we put in our mouth – no?
It’s not just other people’s reassurance and certainty we crave and lap up. We are invited to express strong opinions on complex issues, asserting our own certainty. A recent poll by the market research company IPSOS asked respondents in a variety of countries to what extent they agreed or disagreed with the statement “Restrictions on travel and self-isolation won’t stop the spread of COVID-19 virus”. (Attentive readers will notice that the virus is mislabelled – its name is Sars-Cov-2; COVID-19 is the name of the disease it causes). For most people, including your correspondent, the only sincere answer must be Don’t know. I, and most of my fellow citizens, do not remotely know what the various contagion mechanisms are, what proportion of transmission happens through each of them, how these might be affected by such measures at an individual level and at a community level, to what extent the measures are and will be adopted, when people start and stop being contagious, and so on. Yet it seems that doesn’t stop a huge majority answer as if they do (the highest proportion of Don’t knows is in Germany, just 11%).
We humans are a sophisticated bunch, equipped with a cognitive capacity that outstrips anything in the known universe. Yet when it comes to it, we cannot handle uncertainty. We demand clarity of the black and white kind.
Such binary thinking feeds us distorted images of the world, however. People are either with us, or against us. There is no room in this frame of mind for the equivalent of Schrödinger’s cat: no room for neither agree nor disagree, perhaps because they have not fully studied our position, or they can see both arguments for and against it.
Uncomfortable, but OK
And sometimes we simply do not know. That should be fine. In a paper entitled “I don’t know”, Matthew Backus and Andrew Little, two academics from respectively Columbia and Berkeley universities, conclude that it is in the interest of both good and bad experts to express uncertainty if the effects of certain policies in in political decision-making are impossible to know. I’ll stick my neck out, and add that this would be good advice for non-experts as well.
Not knowing is uncomfortable, though, especially when we feel we need to make a choice. We don’t want to be seen to act on a whim, so the very act of acting must have been inspired by some certainty – even if it is imaginary certainty. Perhaps we rationalize our choices under uncertainty by projecting a rationale backwards? If we have no facts, we can always rely on our priors – like the doctor who advised us to wash our apples and tomatoes with soap.
To some extent, we see this around the controversial topic of the wearing of face masks. Imagine two people, Pat and Chris. Pat believes that face masks, by virtue of being a physical barrier, will be effective at stopping at least some of the contagion we risk when briefly breaking the lockdown/shelter in place to get provisions. Chris believes face masks are crucial for medical personnel who are in close proximity with very sick patients, but that the aerosols that transmit the virus from infected individuals are not going to be stopped by inexpertly fitted masks worn by ordinary people, and that such masks will engender a false sense of security.
Pat and Chris are both right. They will each find evidence to support their view, and this evidence will strengthen their conviction. When they see evidence for the opposing view, they will be suspicious of the source and will discount it. Pat and Chris will assert the correctness of their view with increasing vigour because, like the rest of us, they don’t just exhibit a strong tendency to confirm their priors (you will have recognized the confirmation bias), but also a tendency to persuade others and recruit them for their cause. This predictably gives rise to a self-reinforcing process, by which they will hear echoes of their own advocacy and see them as yet more evidence that they, and they alone are right.
Yet Pat and Chris are simultaneously right – just like Schrödinger’s cat was simultaneously alive and death. The mistake they make is to believe that their rightness, their truth, is absolute – while it is partial and conditional. Even an improvised, ill-fitting face mask will catch some droplets when the wearer coughs, sneezes or speaks, and prevent droplets projected by others from reaching their own mouth or nose. But what proportion of the particles that really matter – droplets or aerosols – are really caught? Neither Pat nor Chris really knows. They don’t know whether wearing a face mask is like a motorcyclist wearing a helmet or a woolly hat. They also don’t know how people will behave when they are wearing face masks, however inadequate. Will they continue to maintain the physical distancing measures and simply treat the masks as extra protection, or will they – because they feel better protected – go out more, and be less conscientious in keeping 2 metres away from others?
If we are interested in the truth, we should be willing to abandon our priors, time and time again. Once we adopt a belief, it will take over and seek protection from us. We will seek to confirm our belief and seek to persuade others, rather than to verify and adjust.
Abandoning our priors means proclaiming our ignorance, however. That is not easy for us, uncertainty-averse creatures that we are. But admitting we don’t really know enables us to accept there are multiple truths, and stops us from caring which particular truth is the ‘real’ one.
That is why it is good to embrace our ignorance. It is by doing so that we can overcome it.