Three words every health expert should learn: I don’t know

Statements of ‘absolute certainty’ from self-styled health experts are dangerous

“One of the most common errors that experts make is to assume that, because they are smarter than most people about certain things, they are smarter than everyone about everything.”

So says Tom Nichols, professor of national security affairs at the US Naval War College, in a recent article in the online magazine Aeon.

His latest book, The Death of Expertise: The Campaign Against Established Knowledge and Why It Matters covers ground well-removed from the shores of naval warfare; his arguments are especially relevant to healthcare.

Over the past few months I have become concerned at some of the "absolute certainty" statements emanating from self-styled experts in the field of health. The media (The Irish Times included) has rightly given voice to a variety of opinions; however, my sense is that some of these opinions have become so absolutist and dogmatic as to inhibit rather than encourage healthy dialogue.


In Nichols’s view, “overconfidence leads experts not only to get out of their own lane and make pronouncements on matters far afield of their expertise, but also to ‘overclaim’ wider expertise even within their own general area of competence. Experts and professionals . . . assume that their previous successes and achievements are evidence of their superior knowledge, and they push their boundaries rather than say the three words that every expert hates to say: ‘I don’t know.’ ”

A reasonable doubt

Emerging as it has in tandem with a widespread phenomenon of false news, such supremacy of expertise feeds a worrying trend: the ignoring of scientific evidence – as seen, for example, among those who are against vaccination – being met with a thunderous Redemptorist-like response where the expert refuses to utter even the slightest hint of reasonable doubt.

Combined, the effect is one of shock and awe – a powerful force of alienation for readers, viewers and listeners, especially the fake news followers.

"Of all the categories of fake news, health news is the worst" ran a recent headline in the Atlantic. According to Kelly McBride, vice-president of the Poynter Institute, the current journalistic environment of quick story turnover creates additional problems for science news, because "the cycle of journalism and the cycle of science are completely incompatible".

McBride suspects that health news may be at a tipping point of bad information, where the audience distrusts the marketplace of ideas, which, she says, “is really dangerous when it comes to healthcare”.

A Kim Jong-un style of expertise doesn’t appreciate this danger. Nor does it acknowledge the ephemeral nature of medical research. Most new medical studies are wrong and cannot be replicated – not because of fraud but because of genuine human error. True expertise looks past the newest science to where knowledge has accumulated over time. It values caveat over conclusion.

Bad at predictive

Nichols points to another problem for experts: prediction. “It’s what the public wants, but experts usually aren’t very good at it. This is because they’re not supposed to be good at it; the purpose of science is to explain, not to predict. And yet predictions, like cross-expertise transgressions, are catnip to experts.”

Experts can be broadly divided into two categories: hedgehogs (who know one big thing) and foxes (who know many things). Hedgehogs tend to be overly focused on generalising their specific knowledge to situations that are outside of their competence, while foxes are better able to integrate more information and to change their minds when presented with new or better data. Foxes' self-critical, point-counterpoint style of thinking prevents them from building up the sort of excessive enthusiasm for their predictions that hedgehogs display for theirs.

“Professionals must own their mistakes, air them publicly and show the steps they are taking to correct them,” Nichols concludes.

And as someone who has experienced the power of “I don’t know” both as a doctor and a journalist, may I gently suggest that “expert” health opinion writers and commentators adopt the humility inherent in the phrase?