Certainty in an Uncertain World

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Commentator Ruth Levy Guyer, a biologist, ponders the uncertainties inherent in some professions, and the kinds of minds that appreciate those uncertainties.


Scientists may not be sure when and where the next pandemic will strike, but commentator Ruth Levy Guyer says some people thrive on that kind of uncertainty.


Every brain has its idiosyncratic way of piecing the world together. Yet miraculously brains work enough alike that we can communicate. We know this because when you say something sad, tears well up in my eyes, and when I start speaking pig latin, ouyay oday ootay, my brain is eager to tell your brain about its certainty hypothesis.

My brain formulated the hypothesis to account for why individuals choose the professions they do. Here goes. A brain will seek a field where uncertainties precisely match the brain's comfort in dealing with uncertainties. This is what's known in science vernacular as a parsimonious hypothesis. It attempts to account for everything that's necessary and sufficient to explain the phenomenon in question, in this case career choices.

Let's test it starting locally with my brain. My first field was immunology. Uncertainty is pervasive. A bumblebee stings five people. The sting has no affect on one, but the second person develops an itchy wheel and flare reaction at the site of the sting. A third breaks out in full-body hives, a fourth grows short of breath and a fifth lapses into anaphylactic shock and dies. This range of outcomes thrills the immunologist for whom the human body is a black box where anything is possible.

My second field is bioethics. Here we dwell in moral dilemmas. Equally good or equally bad options often are pitted against one another. Uncertainty is omnipresent. We love it. So one brain, two fields, both riddled with uncertainties. But this is hardly a proof. Let's now consider the robust certainty needs of others. Mathematicians--they know seven is always seven, period. For them, that's prime. Pascal, the 17th century mathematician said, `It is not certain that everything is uncertain.'

A subset of mathematicians, the geometricians, devise theorems about solids and planes and then hatch absolute proofs. And speaking of planes, what about flight controllers? Certainties are crucial. They and we require that controllers can precisely orchestrate the movements of aircraft in the skies. For flight controllers, black boxes are real, not metaphoric.

Envision then a chart on which brains are lined up according to their acceptance of uncertainties, something similar to the graphic depicting the evolution of Homosapiens from the apes. You know, where at one end the apes are hobbling along on their knuckles and at the other end stand the upright citizens. Clustered at one end of the brain diagram are brains of mathematicians, flight controllers, other certainty mavens. Situated at the other end are brains of bioethicists, immunologists and others with hang loose attitudes toward certainties. For diplomacy's sake, I demur here from commenting on which end includes the brains that I consider most highly evolved.

LYDEN: Ruth Levy Guyer teachers at Haverford College and Johns Hopkins University at certain times of the year.

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