Bruno, Semmelweis, and McCarthy


Bruno, Semmelweis, and McCarthy:
Declaring war against the Establishment; what is it good for?

Over the past several months, Neil DeGrasse Tyson has done a masterful job of narration on “COSMOS: A Spacetime Odyssey“. The very first episode of this show introduced viewers to the historical cosmologist Giordano Bruno. A quick recap:

Giordano Bruno promoted a heliocentric view of the universe way before it was cool. In the 16th century, spouting garbage about the Earth revolving around the Sun was a dangerous heresy. After all, everyone knew the Earth was created at the center of the universe – it says right there in the Bible. Geocentrism was supported by an overwhelming consensus among the educated classes, as well as foolproof scientific evidence – the absence of stellar parallax.

Astronomers have charted the stars since time immemorial, and the “fixed stars” traced the same paths year after year. Any village idiot could rotate an astrolabe around its axis – the Earth – and see for themselves. An astrolabe was precise. You could navigate by an astrolabe. If you placed the Earth anywhere off the central axis, the geometry would fall apart and the damned thing would never work.

So of course Bruno was a heretic. He was imprisoned, tortured and executed by the Church.

Over a decade after Bruno’s death, Galileo Galilei popularized the heliocentric model of the stars. Galileo was also persecuted, but was allowed to live under house arrest.

Stellar parallax would not be directly observed until two centuries later. By then, the Church had no problem with heliocentricity.

Now that we’re in the mid-19th century, we can look around for our second tragic genius. Dr. Ignaz Semmelweis witnessed the epidemic of fatal childbed fever that was sweeping Europe at the time. The good Doctor became convinced that disease was transmitted by “cadaveric particles” that could be removed by handwashing with chlorinated lime (aka bleach). He performed clinical trials, showing a dramatic improvement in survival with antiseptic handwashing.

Had there had been an Affordable Care Act of 1847, it would have made bleach-based handwashing a quality reporting measure. 19th century telegraph operators would have been busy copying “Did you wash your hands with bleach?” into dots and dashes on bronze templates, fully compliant with His Royal Apostolic Majesty’s Meaningfulle-Utilization Decree. Unfortunately for Dr. Semmelweis, Emperor Ferdinand I was too busy being deposed to pass comprehensive healthcare reform.

So Semmelweis did what any good physician would do, if he were an actor playing a physician on a medical television drama. He went around accusing his medical colleagues of being unclean, irresponsible, even “murderers”. The establishment rejected him so violently that he went insane and was imprisoned against his will in a mental asylum. Or was it the other way around?

Over a decade after his death, Semmelweis was finally recognized as correct. Louis Pasteur published the germ theory of contagious disease, which immediately went viral.

Much, much later, people coined the term “Semmelweis Reflex” to describe the human tendency to reject new information.


Both Bruno and Semmelweis had a revolutionary idea that contradicted everything the “scientific establishment” believed at the time. Both men decided to fight the establishment despite considerable risk to their health and sanity. In both cases, the clash ended like you’d expect.

This tragic fate has elevated Bruno and Semmelweis to Leonidas status among many people with unpopular beliefs. If Bruno and Semmelweis were crushed under the heel of the establishment, then surely more geniuses were suppressed to the point where we never heard about them. God only knows how many transformative worldviews were lost to mankind thanks to the reactionary mainstream… In fact, any time you see an idea forcefully suppressed, that idea must be trueOtherwise the establishment wouldn’t waste its time on oppression.

Semmelweis has been quoted by a crowd as diverse as anti-vaccination activistsclimate change activists, climate change deniers, and Major League Baseball agents. The idea that “conventional thinking is wrong” has obvious appeal to anyone with beliefs just crazy enough to be true. (not least of all the agent representing an athlete who is so much more skilled than what he shows on film, or in workouts, or in interviews)

As you might expect, plenty of nonsense-peddlers quote the Semmelweis Reflex to justify their beliefs.


The problem with Bruno and Semmelweis is two-fold:

First, neither one was actually right. Giordano Bruno based his cosmology on speculation and (weird) theology. He wasn’t an astronomer, he didn’t have any evidence, nor did he bother collecting any. Semmelweis based his handwashing practice on the theory of “cadaverous particles”. He didn’t try to explain what cadaverous particles were, how to measure them, or how they fit into our understanding of biology. Both Bruno and Semmelweis stumbled into correct conclusions through methods that were closer to magical thinking than to science.

Second, both men went out of their way to antagonize the establishment. While being a jerk doesn’t justify a painful early death (usually), there’s no doubt that Bruno and Semmelweis did a lot to harm their own causes. Bruno publicly doubted the Trinity, the virgin birth, and the divinity of Christ. He called his fellow friars “asses” and went around claiming to teach people magic. He probably pissed in the holy water too. It’s not a surprise that the Church killed him for his heresies.

Semmelweis wasn’t quite as far-out there, but he also did not help his own cause. He performed a controlled trial to demonstrate the efficacy of handwashing with antiseptic technique (good science!) and then firmly tied handwashing to his belief in harmful “cadaverous particles” / “cadaveric matter” (bad science!). When his contemporaries presented him with evidence that sepsis could occur even without a cadaver, Semmelweis mostly ignored them and continued to push his wrong-headed cadaver theory. Semmelweis’s attachment to his pet theory worked against the adoption of his real-life practice of antisepsis. If he’d been a little more flexible on cadaver theory, antiseptic handwashing may have been popularized years before Louis Pasteur, saving hundreds of thousands more lives.

With that in mind, Bruno and Semmelweis can teach us more than just “groupthink = bad”. The fact is, many of the great ideas throughout history were quite unconventional at the time. Before Isaac Newton, the “scientific consensus” would have said that a large weight falls faster than a small weight. Before Albert Einstein, only madmen believed that movement through space could distort the passage of time. Before Jim Watson, everyone knew that genes were made of proteins and not DNA. All three men were celebrated, not ridiculed for their unconventional genius.

The problem with Bruno and Semmelweis is that they went beyond “unconventional” and into what I’ll call “anti-conventional”. They didn’t just spit in the eye of the establishment, they turned around, dropped their drawers and farted. They pissed off their peers just because they could, and then it turned out that they really couldn’t.

No human is completely immune to ad hominem bias; when someone you dislike presents the facts, your first reflex is suspicion. You search for the deception or manipulation behind his logic, and nit-pick any small flaws in his data. Then you present a rebuttal with your own data and theory, and your opponent quickly sets about refuting your evidence. A demented version of Clarke’s Law takes hold: any science sufficiently politicized is indistinguishable from bullshit.

That’s why even though I agree that anti-vaxxers are dangerously wrong, I also disagree with the strategy of shaming and blaming them (complete with the occasional wave of anti-anti-vax Facebook “Share”s). People with fixed false beliefs are not going to change just because someone tells them how wrong they are. A better strategy is a combination of harm reduction (not making vaccine exemptions trivially easy to get), education (infectious disease is bad, y’all), and limiting the number of public platforms where they can shout nonsense.

It’s very unlikely that any of us can change anyone’s deeply held wrong beliefs, but we can all hope to limit the spread of such beliefs. After all, an idea is the deadliest parasite.

Now if only we had a mental equivalent of handwashing with bleach.