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Certainty in Uncertainty

By Salil Patel

Ideas are figments of the mind, not properties of the natural world. Yet evidence from recent months suggests that ideas, birthed by fear, walk amongst us in the form of armchair epidemiologists, government conspiracists and novice vaccine virologists. The inner workings of intensive care have never been so well understood by so many. The importance of ventilators is trumpeted and the public belatedly acknowledge the miraculous work ethic of nurses. The tools of medicine—gadgetry beyond the dreams of forebears—are still very much dependent on a mesh of grey gelatinous matter defined by an unparalleled ability to create, and to empathise with others. But for all the wizardry and wonder at the disposal of modern medics, uncertainty is the hidden lesson we are forced to learn.

One of the overarching axioms of medicine states how little we know and how much of what we do is based on scant evidence, for lack of better alternatives. This uncertainty is the foundation for all research. And this uncertainty is what threads medicine the art to medicine the science. Never has such a lack of knowledge been on public display. The case-fatality ratio, severity, pathophysiology and evolution of Covid-19 have been mapped in real time. Yet we still know little about the pandemic. Such uncertainty is not well understood by the public nor well tolerated by the media. The trickery of the virus—its ability to target the exact process we use to sustain life, in order to end it—is nature rearing its genius. A similar genius will be needed to strike a counterpunch. Work is well underway but uncertainty will be our overriding emotion for the foreseeable future.

Our brains are wired to minimise uncertainty. Changes in our environment set off alarm bells, and we become hypervigilant. This primal state consumes energy, so we become tired. In normal circumstances, neurons in the cortex (the rational part of the brain) and amygdala (the emotional part of the brain) help assess and respond to change by decreasing uncertainty. Simply put, the electrical activity produced by the interactions between these neurons increases our attention and enhances our ability to gather information. Information, it is thought, is the natural product of diminished uncertainty. This loop is therefore designed to minimise uncertainty quickly and allow the body to recuperate from an acute stress response, regathering expended energy. This allows us to relax.

However, when uncertainty is not diminished quickly—say, in the midst of a pandemic—the loop is not switched off. Chronic continuous activity in these areas of the brain (termed allostatic load) can lead to high blood pressure, turbulent blood flow, depressed moods, and cognitive dysfunction. We can become ill, tired, upset, and foolish. Longer-lasting effects can result in more serious damage, and heart attacks and strokes can follow. As if economic catastrophe, political deceit and legislated isolation were not enough to contend with, nature has primed us to reduce uncertainty. Our physical and mental health depend on it.

Perhaps a natural predisposition to reduce uncertainty explains our general unwillingness to face our other existential adversity: climate change. We look towards alternative explanations for noticeable shifts in weather, finding hope in historic meteorological cycles oscillating between ice ages and heat waves. When climate scientists tweak global carbon dioxide measurements or provide ranges instead of individual values we write opinion pieces concluding that such uncertainty is a sign of foolishness; scientists may be wrong once again. Society is not designed to respect change. We are not designed to cope with change. Uncertainty breeds mistrust.

Here lies a key difference between politics and science. Among politicians, flip-flopping is regarded as a cardinal sin. Many campaigns have been tainted by individual policy U-turns. Uncertainty in the midst of power is seen as dangerous. The realm of politics may well perpetuate neural urges to reduce uncertainty. We seek comfort in demagogues who scream assurances, and often at the expense of more tempered souls willing to learn, adapt and admit to a lack of knowledge.

Yet the very foundations upon which modern political systems have been built are uncertain. They are disassembled and rearranged by revolutions and amendments, peaceful adaptations and violent upheavals. Empires fall and revolutions fade. Our precious institutions are liquid. Putting aside the different forms of aristo/pluto/theo/techno-cracies, there is no uniform democracy across the globe. Vast differences exist between systems that are direct or representative, parliamentary or presidential. Opinion columns bifurcating the political spectrum stir our emotions by ridiculing changes in politicians’ opinions, yet perpetually call for grander changes across government. Individual uncertainty is punished while institutional uncertainty is demanded and devoured by our wolfish minds. This inconsistency is a staple of the political realm.

In the scientific arena, by contrast, certainty breeds mistrust. Science is simply the accumulation of knowledge based on evidence—though it is a universally-acknowledged truth that evidence changes: so, then, does the science. Though gaps in knowledge have never been better publicised, it is important to remember gaps in epidemiology are no wider than those in inorganic chemistry or evolutionary biology. Even in our pre-pandemic era, scientists were more comfortable being orchestrated by uncertainty, the result of a long-standing Faustian pact with nature.

Uncertainty can define both the mindset of scientists and the science itself. The uncertainty principle underpinning the field of quantum mechanics, formulated by Werner Heisenberg in 1927, attempts to define the opacity of what we can know to be true. It outlines how the position (x) and momentum (p) of any given particle cannot be measured precisely at the same time. If we concentrate on measuring either x or p as accurately as possible, the unmeasured property will be less accurate. This seems counterintuitive. We can measure the position and momentum of a car with simple devices and elementary mathematics. Sub-atomic particles, however, behave strangely and do not abide by the classical laws of mechanics: thus, the discipline of quantum mechanics was born to deal with the miniscule. Sub-atomic particles, like electrons, do not exist in a single place at a given time as a car moving along a road does. It is easier to visualise electrons in terms of existing in a cloud of probabilities, or what is called their atomic orbit. They can exist anywhere inside that cloud at any given time, meaning that a large effort is needed to measure a position as accurately as possible.

There is, however, one known that we can rely on. Planck’s constant—a tiny number with 33 zeros after the decimal place—is a fundamental, never-changing property of the quantum world, which defines the atomic interaction of particles and waves. There is, according to Planck’s constant, some certainty in uncertainty. The principle dictates that we cannot know precisely both the position and momentum of a particle. The errors in position (Δx) and errors in momentum (Δp), when multiplied together, must be greater or equal to Planck’s constant (h/2π). Thus, the smaller the error in x, the larger the error in p:

The uncertainty principle forces us to choose which, out of position and momentum, to pursue. This pandemic is filled with similar trade-offs. Isolating from others lessens our liberties. Suffering alone protects loved ones. The constant to which we are all tied is not defined by the energy of electrons but instead inextricably linked to the energy sustaining relationships. Paradoxically, we have been told that the strength of relationships with those closest to us is reliant on ignoring evolutionary urges. We must stay away. Acts of love have become sub-atomic—invisible—yet still organise our lives.

Richard Feynman, another gloriously uncertain quantum physicist, remarked: ‘I have approximate answers and possible beliefs and different degrees of uncertainty about different things, but I am not absolutely sure of anything and there are many things I don’t know anything about’. Changing one’s mind in the face of new evidence is the first step of every discovery mankind has ever made. Seeing as creatures are destined, if perhaps not designed, to live without clear answers, we should seek comfort in this. History suggests nobody is born a politician; rather, it seems we are all natural scientists, filling gaps in our knowledge one stumble at a time.

Art by Ollie Cowley


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