The Only Certainty Is Uncertainty: Stuart Firestein on Science in the Age of Tony Fauci

“Uncertainty is what tells you that science is reliable. It’s the people who are absolutely certain that you have to watch out for.” — Stuart Firestein

The physician-scientist Tony Fauci is having a rough week. His newly revealed diary has even disappointed traditional allies at The Atlantic and The New Yorker who see the hitherto liberal saint of the pandemic as both too intimate with power and too certain of his scientific assumptions.

Fauci’s fellow American scientist, Stuart Firestein, is having a better week. The Columbia neurobiologist has a new book out today, It Could Be Otherwise, which is a manifesto against scientific certainty. It’s the certain ones you have to watch out for, Firestein warns about those scientists intoxicated with the certainty of their own doctrines.

Science, Firestein argues, requires a blend of hubris and humility. So the great Isaac Newton needed real chutzpah to claim to understand the mind of the creator with only a few equations. The expert is, by definition, riddled by doubt. They should be the most uncertain person in the room. Thus for Firestein, Charles Darwin is a greater scientist than Albert Einstein because Darwin’s theory of life is premised on randomness.

So will contemporary science appear quaintly medieval in 500 years? Will 26th century man think of Darwin and Einstein like we moderns patronize Aristotle? Probably, Firestein suggests. In his Columbia course on ignorance, he tells his students that getting an A requires getting an F. We should all be so ignorant.

Five Takeaways

•       Watch Out for the Certain Ones. Firestein won’t defend Fauci’s certainties, but he explains them: science requires a blend of hubris and humility — without some hubris, nobody would attempt a discipline that is mostly failure, mostly time spent in the dark. What corrupts the blend is a culture that demands the opposite of humility: exams with one right answer instead of ranked possibilities, journalists who need a confident quote, a public that has made science the theology of the twenty-first century. The result is Firestein’s paradox of expertise: the real expert is the most uncertain person in the room, because expertise means seeing the holes, the missing data, the failures. Certainty grows with distance from knowledge.

•       True Enough. Truth gets a small t only. Borrowing from the Harvard philosopher Catherine Elgin, Firestein describes science as moving from one provisional truth to the next — “true enough,” always improving, never final. His favorite proof is John Maddox, Nature’s longest-serving editor, asked how many of the journal’s published papers would prove wrong: “Oh, that’s easy. All of them.” Not wrong-wrong — unsettled science is not unsound science; it is reliable and it will get better. In science, revision is a victory, which is why Firestein sincerely hopes that in five hundred years our best knowledge will look as quaint as medieval astronomy — which, he notes, was accurate enough for people who weren’t launching satellites.

•       Two Kinds of Uncertainty. Epistemic uncertainty is what we don’t know yet; ontological uncertainty is the irreducible complexity of the universe itself — so complicated it might as well be random. Every answer in the lab raises ten better questions, which is how the more we know, the less we know. And yet we thrive amid the not-knowing: lasers, GPS, and randomized drug trials are all built on uncertainty. Ninety percent of hypertension diagnoses are idiopathic — no known cause — while nine different families of medicine treat it successful