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Do experts say ‘I don’t know’ more or less than non-experts?
In Nate Silver’s 2012 bestseller The Signal and the Noise, he suggests that ‘mathematics classrooms spend more time on abstract subjects like geometry and calculus than they do on probability and statistics. In many walks of life, expressions of uncertainty are mistaken for admissions of weakness.’1
In juxtaposing these two elements, Silver leads us to believe that more time on the one might mitigate the other. Is it important that we know how certain we are about what we know? What about knowing what we don’t know? (Can we ever know this?) What has probability and statistics got to teach us about navigating truth (and post-truth)?
In fact, much of the statistics and probability learned in schools may even compound the issue. The study of these is often reduced to simplistic questions in which learners are either required to make definitive statements based on uncertain sample data or focus on expected outcomes rather than variation. If statistics and probability are ‘mathematised’ to the point that learners believe them to be largely deterministic, what message does this send about uncertainty in the wider world? And where else are they going to get the message that some things can never be known with absolute certainty, and that this does not mean we cannot learn from these things despite this uncomfortable truth.
In a famous speech in 2002, then United States Secretary of Defense Donald Rumsfeld said ‘Reports that say that something hasn't happened are always interesting to me, because as we know, there are known knowns; there are things we know we know. We also know there are known unknowns; that is to say we know there are some things we do not know’.
As one research paper tells it, ‘as a result, he was almost universally lampooned since many people initially thought the statement was nonsense. However, careful examination of the statement reveals that it does make sense, indeed the concept of the unknown unknown existed long before Donald Rumsfeld gave it a new audience’.2
Within the category of ‘known knowns’ it is fascinating to consider ‘things we know we know but don’t know right now.’ In other words, sometimes we know we know something, but can’t recall it at that moment. ‘The feeling of knowing the information despite being unable to retrieve it from memory is called the feeling of knowing (FOK)’ (Roberts and Rhodes, 1989)3. I know this feeling as it often presents as anomia (informally – it’s on the tip of my tongue; more formally, a medical condition of forgetting the names for things) – and I know this word from the board game of the same name, which recreates this feeling effortlessly thus:
During this game, where one might have an audience watching while trying to recall a type of breakfast cereal or bicycle manufacturer as quickly as possible, players often experience the feeling of knowing – that is, they are aware the information is in there ‘somewhere’ but retrieval is blocked, delayed or downright impossible at that particular moment.
Despite the fact that this has likely happened to all of us at some point, how would or do we deal with experts who justify themselves with this ‘excuse’? Is it better for one’s credibility to say ‘I don’t know’ than to say ‘I know I know, but I don’t know right now’?
Silver suggests, in his chapter on climate change, that the public debate has been (perhaps permanently) skewed by the necessarily ‘uncertain’ nature of scientific belief – that the media has been filled with the ‘street fight’ between cautious experts and confident politicians, explaining that scepticism is seen as a central tenet of science, but ‘in politics, one is expected to give no quarter to his [sic] opponents.’ This brings to mind these lines from ‘The Second Coming’ by W.B. Yeats:
The best lack all conviction, while the worst
Are full of passionate intensity4
How much trust do you place in people who say ‘I don’t know’, and on what basis?
1Silver, N. (2012). The signal and the noise: the art and science of prediction. London: Allen Lane, Penguin Books.
2Logan, D. C. (2009). Known knowns, known unknowns, unknown unknowns and the propagation of scientific enquiry. Journal of Experimental Botany, 60(3), 712–714.
3Roberts, L.S. & Rhodes, G., (1989). Knowing Your Limits: Expertise and the Feeling of Knowing. New Zealand Journal of Psychology, 18,71-75.
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