We Need Scientific Dissidents Now More Than Ever

In 2023, nothing seems more obvious than the fact that doctors should wash their hands in between patients. But this wasn’t always the case. And we owe our knowledge of this “obvious” fact to one of the most famous scientific dissidents in history: Ignaz Semmelweis. In 1846, the Vienna General Hospital had two free obstetric clinics, where underprivileged women, including prostitutes, could go to receive not only child-birthing services, but also free postpartum care for their infants. In return for the free services, the new mothers agreed to be used as subjects for the training of doctors (in the first clinic) and midwives (in the second). But giving birth in the first clinic was extremely dangerous. Almost one in 10 women who gave birth there died of puerperal fever. The rate of childbed fever was much lower in the second clinic. As word got around about this, women who knew they would be assigned to the first clinic sometimes deliberately contrived to give birth on the street, as if on the way to the hospital, so they could receive the free infant care without being subjected to the clinic’s obstetric services. The women who gave birth on the street rarely if ever contracted puerperal fever.

Semmelweis, a young physician who worked in a position comparable to what we would today call a “resident,” was one of the few people bothered by these facts. He became obsessed with figuring out why one clinic fared so much worse than the other. In 1847, one of Semmelweis’s friends was accidentally cut by a colleague’s scalpel while they were carrying out an autopsy. The friend died several days later, while exhibiting many of the same symptoms and postmortem signs as the women who died of puerperal fever. This led Semmelweis to hypothesize that the cause of the high death rate in the first clinic was the fact that medical students were carrying “cadaverous particles” from the autopsies of their anatomy lessons to their examinations of pregnant women. After experimenting with a few different cleansing agents to determine which one did the best job of removing the putrid smell of cadavers, Semmelweis proposed that medical students wash their hands with chlorinated lime between their autopsies and their examinations of patients. The mortality rate in the first clinic promptly fell by 90 percent.

What happened next tells us a lot about how scientific dissidents are treated. Semmelweis was ridiculed and driven out of the Vienna hospital, indeed out of Vienna entirely. He eventually died in a psychiatric hospital in Hungary after suffering a severe beating at the hands of the asylum guards. This kind of treatment of the dissident scientist is sometimes called the “Semmelweis reflex,” which Timothy Leary defined as “mob behavior found among primates and larval hominids on undeveloped planets, in which a discovery of important scientific fact is punished.”

Yet the dissident scientist is so important precisely because, as the philosopher and historian Thomas Kuhn emphasized in his seminal work The Structure of Scientific Revolutions, scientific communities excel at protecting their entrenched theories from inconvenient new observations and evidence. Kuhn emphasized that scientific progress comes in two very different forms, each relying on very different styles of thinking. The first kind of progress he called “puzzle solving.” This involves accommodating all of those inconvenient observations and bits of evidence into the existing framework. It’s easy to read Kuhn as denigrating this kind of work (he called it the very-boring-sounding “normal science”), but nothing could be further from the truth. This is the process, according to Kuhn, by which scientific frameworks get their richness, complexity, and explanatory power.

Puzzle solving, however, actually requires a dogmatic commitment to the existing framework. You can’t fill out the rich complexity of a scientific framework if you are always distracted by shiny new ideas. Eventually, though, science needs to advance via the second kind of progress. This is the much-more-exciting-sounding “revolutionary science” that Kuhn is famous for describing. But the central importance to science of “normal,” everyday puzzle solving, and the dogmatic commitment to the existing framework this requires, throws the Semmelweisses of the world into an extremely challenging role. As crucial as their role is to the longer arc of scientific progress, it also cuts against the grain of what most scientists are trained to do, which is to defend the existing framework.

Historians disagree about why Semmelweis’s views were ignored, even though it was clear his recommendations were working. Was it because he offered no mechanism (the germ theory of disease would only come 20 years later), or because he didn’t explain his views well, or because the high-status doctors at the Vienna hospital were offended at the idea that they needed to wash their hands before touching prostitutes? Perhaps it was none of these. Perhaps the humoral theory of disease, rooted in sacrosanct thinking that went back to Aristotle, Galen, and Hippocrates, was too deeply entrenched for any thinking based on different premises to make a dent. This is the Kuhnian picture.

But the scientific dogmas that dissident scientists have to overcome don’t always have such ancient and prestigious pedigrees. Consider the case of the role of dietary sugars and fats. In the 1950s, American men began to die of coronary heart disease at a much-higher rate than elsewhere in the world. Diet seemed to be the likely culprit. But what aspects of the American diet are to blame remains a topic of uncertainty. By the 1960s, there were two prominent hypotheses: added sugar on the one hand, and total dietary fat, saturated fat, and cholesterol on the other. Physiologists were divided on the subject; John Yudkin advocated for the sugar hypothesis, while Ancel Keys identified fats and cholesterol as the primary culprits.

By 1980, few scientists believed sugar played a role in heart disease, and the 1980 Dietary Guidelines for Americans focused on reducing total fat, saturated fat, and dietary cholesterol. Where did this consensus come from, and how did it emerge so quickly? The answer reveals a process of consensus formation that occasionally occurs in science and is far-less distinguished than our traditional picture.

At the heart of the story was an organization called the Sugar Research Foundation (SRF). On July 11, 1965, the New York Herald Tribune published a story, based on research published in Annals of Internal Medicine, which reported a much-stronger link between sugar and heart disease than had been previously supported. Two days later, the SRF approved “project 226,” the commissioning of a literature review that was designed to discredit the science behind the link between sugar and heart disease and establish a consensus around fats and cholesterol. In total, the SRF would spend over $6.5 million (in 2023 dollars) establishing this consensus. By the time the 1980 guidelines were out, the effort had decisively succeeded.

What the sugar episode reveals is this: Sometimes, a scientific consensus is established because vested interests have diligently and purposefully transformed a situation of profound uncertainty into one in which there appears to be overwhelming evidence for what becomes the consensus view. When a scientific consensus emerges via this accelerated process, the role of the scientific dissident is not, like Semmelweis, to carry out revolutionary science. The dissident’s role is to provide a check against epistemically detrimental and artificial consensus formation. Nevertheless, the challenges faced are similar. Never has this accelerated process unfolded with such success, and such fury, as in the case of the origins of the SARS-CoV-2 virus.

The Covid-19 pandemic certainly saw its share of scientific dissidents. Public-health experts in Sweden as well the signatories of the so-called “Great Barrington Declaration” challenged the claim that lockdowns would bring net health and well-being benefits to the citizens of communities that enacted them. The economist Emily Oster gathered data showing that the risks of reopening schools was low. The British epidemiologist and evidence-based medicine expert Tom Jefferson and his group at the Cochrane Collaboration, one of the most-distinguished compilers of systematic reviews of medical evidence in the world, argued that mask mandates were not preventing the spread of the virus. The oncologist and biostatistician Vinay Prasad argued that young people at low risk of serious illness were being given (and, in some cases, being forced to take) too many doses of vaccine.

Many of these “Covid dissidents” were treated quite badly. They were widely vilified by both the mainstream scientific community as well as by the public. Many had their arguments and interviews censored on social media and content-hosting sites like YouTube. Often, the large tech firms behind these platforms coordinated with the U.S. government on what ought to be censored. A few were targets of coordinated attempts by government bureaucrats to discredit them. In October 2020, Francis Collins, then the director of the National Institutes of Health, emailed Anthony Fauci, then the director of the National Institute of Allergy and Infectious Diseases, to say that The Great Barrington Declaration “seems to be getting a lot of attention — and even a co-signature from Nobel Prize winner Mike Leavitt at Stanford. There needs to be a quick and devastating published take down of its premises … Is it underway?” John Ioannidis, whom The Atlantic called “one of the most influential scientists alive” (he has over half a million citations to his name) had his video “Perspectives on the Pandemic” censored by YouTube. When Tom Jefferson and his group published a report saying “We are uncertain whether wearing masks or N95/P2 respirators helps to slow the spread of respiratory viruses based on the studies we assessed,” the editor in chief of Cochrane apologized for the wording, even though subsequent surveys showed the language was standard for Cochrane given the nature of the evidence.

We also know that many social-media sites “shadow banned” people for posting scientifically dissident information — dramatically limiting the reach of their posts. According to the journalist David Zweig, “The United States government pressured Twitter and other social media platforms to elevate certain content and suppress other content about Covid-19.” On Twitter, even tweets displaying official CDC data were labeled “misleading” if they highlighted uncomfortable, but factual, claims — such as one that showed that, in fact, Covid-19 was not the leading cause of death in children during the pandemic. All of this behavior was classic Semmelweis reflex.

But few scientific dissidents in the pandemic were treated with as much scorn and reprobation as those who challenged the consensus regarding the origins of SARS-CoV-2. As early as the fall of 2020, some researchers started to make a serious case that the virus might have been engineered in the course of “gain-of-function” (GoF) research undertaken at the Wuhan Institute of Virology, and subsequently accidentally released into the general population of Hubei province — the so-called “lab-leak” hypothesis. The attitude of the scientific community regarding these dissidents was well expressed in a February 19, 2020, letter in The Lancet titled “Statement in support of the scientists, public health professionals, and medical professionals of China combatting COVID-19,” written by a group of 27 researchers from medicine, biology, virology, epidemiology, and public health. They wrote:

Scientists from multiple countries have published and analysed genomes of the causative agent, severe acute respiratory syndrome coronavirus (SARS-CoV-2), and they overwhelmingly conclude that this coronavirus originated in wildlife, as have so many other emerging pathogens. This is further supported by a letter from the presidents of the US National Academies of Science, Engineering, and Medicine and by the scientific communities they represent. Conspiracy theories do nothing but create fear, rumors, and prejudice that jeopardise our global collaboration in the fight against this virus. We support the call from the Director-General of WHO to promote scientific evidence and unity over misinformation and conjecture.

When this letter was cross-posted on Change.org, it received over 20,000 signatures, many of them by people representing themselves as relevant domain experts. We now know the letter was orchestrated by fifth author Peter Daszak, the president of EcoHealth Alliance, which has millions of dollars of funding for the kind of research that might be called into question if the lab-leak hypothesis were accepted. He wrote privately that he wanted the letter to “avoid the appearance of a political statement.”

The Lancet letter, and other efforts like it to circle the wagons, created a line in the sand that few dared to cross. One prominent public figure who did so was the comedian Jon Stewart. Appearing on his former colleague Stephen Colbert’s late show, Stewart quipped, “There’s been an outbreak of chocolatey goodness near Hershey, Pennsylvania — what do you think happened?” He was implying, of course, that it was no coincidence that a new strain of SARS emerged in the same city as a virology institute famous for studying coronaviruses that emerged from bats.

Throughout the pandemic, any scientific heterodoxy, but especially heterodoxy about the virus’s origin, was treated as a mark of affiliation with a set of unsavory political views associated with the supporters of Donald Trump. But few people in the world had a better claim not to be affiliated with the Trumpist right than Jon Stewart. Nevertheless, the condemnatory response was swift and severe. Colbert immediately asked Stewart how long he had been working for Republican Sen. Ron Johnson. “The two things that came out of it were,” Stewart later said, “I’m racist against Asian people, and how dare I align myself with the alt-right.” He added, “The larger problem with all of this is the inability to discuss things that are within the realm of possibility without falling into absolutes and litmus-testing each other for our political allegiances as it arose from that.”

Of course, Stewart is not a scientist, but some scientists, including the molecular biologist Richard Ebright, the data scientist Gilles Demaneuf, the molecular biologist Alina Chan, and the former CDC director Robert Redfield, got similar treatment. In testimony to the House of Representatives’ select subcommittee, Redfield said, “It was told to me that they wanted a single narrative, and that I obviously had a different point of view. … Science has debate and they squashed any debate.”

I suspect we will never know the full truth about the origin of SARS-CoV-2. I certainly make no claim to knowing it. But what we do now know is that Stewart, Demaneuf, and Redfield were subjected to the Semmelweis reflex not because of the strength of evidence that they were wrong, nor because, like Hippocratic medicine, the view they were challenging had a long history or was an entrenched worldview. In fact, the consensus that “scientists from multiple countries” had “overwhelmingly” settled on — that SARS-CoV-2 had originated in wildlife — was concocted in a hurried conference call, over a few emails, and in a group conversation on Slack in the days between February 1 and 4, 2020. These conversations culminated in the submission, on February 4, to Nature Medicine, of “The proximal origin of SARS-CoV2.” That paper famously concluded that “Our analyses clearly show that SARS-CoV-2 is not a laboratory construct or a purposefully manipulated virus.”

It is fair to say this conclusion was “concocted” because of the evidence that its authors themselves did not believe it. On February 1, the Danish biologist Kristian G. Andersen wrote in the Slack channel: “I think the main thing still in my mind is that the lab escape version of this is so friggin’ likely to have happened because they were already doing this type of work and the molecular data is fully consistent with that scenario.” But by February 4, he was lead author of a submission that “clearly showed” the virus was “not purposefully manipulated.” The second author of “Proximal origins,” Andrew Rambault, wrote, on Slack, “I literally swivel day by day thinking it is lab escaped or natural.” Another of the authors, W. Ian Lipkin wrote, “Given the scale of the bat Cov research pursued there and the site of its emergence of the first human cases, we have a nightmare of circumstantial evidence to assess.” In testimony to Congress, Lipkin said that “Dr. Holmes became very unhappy with me after I refused to sign on and say that, you know, there was proof that this is where this began, in the wet market.” Lipkin was referring to the paper’s fourth author, Edward Holmes, who privately wrote, “China are definitely trying to rewrite what happened,” and “No way selection could happen in the market.” The fifth author Robert Garry wrote, “It’s not crackpot to suggest [someone inserting a furin site in RatG13] could have happened given the Gain of Function research we know is happening.”

Why did they all change their minds over the course of those three days? Their official story was that new data from pangolins explained some of the anomalies in the virus that made the molecular data look “fully consistent.” But in a February 20 email, Andersen admitted that “Unfortunately none of this [pangolin data] helps refute a lab origin and the possibility must be considered as a serious scientific theory.” In the Slack channel, he gave us the real answer: “I hate when politics is injected into science — but it’s impossible not to, especially given the circumstance.” And as late as April 16, 2020, he wrote to his co-authors that “I’m still not fully convinced that no culture was involved. We also can’t fully rule out engineering (for basic research)”

We now know that the February 1 conference call included Anthony Fauci, Francis Collins, Christian Drosten (sometimes known as the “Fauci of Germany”), and his Dutch counterpart Ron Fouchier. Fouchier and Drosten have both been strong supporters of GoF research. Fouchier helped to draft the paper but did not want his name included as an author. All four pushed hard for the lab-escape hypothesis to be ruled out in the paper. The next day, on February 2, Andersen had this to say, on Slack, about the conference call:

In the end, it certainly appears that the interests of the four non-authors on the call, Fauci, Collins, Drosten, and Fouchier, prevailed over the scientific judgment of the five authors. Nothing else explains the nearly instantaneous shift from “so friggin’ likely” to “clearly not.” And this was despite the fact that the lead author thought that at least two of the four non-authors were “much too conflicted to think … straight.”

Scientific dissidents will never be popular. We associate them with crazy views like “climate change is a hoax” and “childhood vaccines cause autism.” The Semmelweis reflex runs strong in all of us. Not even a figure as beloved as Jon Stewart is immune. But the world isn’t simple, what the evidence shows isn’t always clear, and things are not always as they seem. So we owe the Semmelweisses of the world a debt of gratitude — for their diligence and their courage. This doesn’t mean we should believe every heterodox thinker that comes along. But it means we should strongly resist the urge to punish them, to censor them, to call them racist, and to evaluate their claims by, in Stewart’s words, “litmus-testing each other for our political allegiances.”